The Eye and Sports Medicine
PAUL F. VINGER
Table Of Contents
ECONOMICS OF SPORTS EYE INJURIES
MECHANISMS OF SPORTS EYE INJURIES
PRINCIPLES OF PREVENTING SPORTS-RELATED EYE INJURIES
EQUIPMENT CERTIFICATION COUNCILS
OBSOLESCENSE IN PROTECTIVE EQUIPMENT
GUIDELINES FOR SPORTS PARTICIPATION
RISK OF EYE INJURY AND EFFECTIVENESS OF PROTECTIVE DEVICES FOR SPECIFIC SPORTS
VISION PERFORMANCE AND TRAINING
LEGAL IMPLICATIONS OF SPORTS-RELATED EYE INJURIES
ROLE OF EYE-CARE AND ATHLETIC PROFESSIONALS IN EYE INJURY PREVENTION
|The ideal scenario for a sports (or any other) eye injury is for it never to have happened. Prevention, which is effective in terms of injury reduction and cost savings to society,1–6 should be part of the core curriculum of anyone who prescribes, manufactures, or dispenses eyewear, as well as those in the capacity of formulating and implementing rules in the athletic environment.7 According to the Centers for Disease Control and Prevention, “Injury is probably the most unrecognized major health problem facing the nation today, and the study of injury presents unparalleled opportunities for reducing morbidity and mortality and for realizing significant savings in financial and human terms—all in return for a relatively modest investment.”8 By following the guidelines for specific sports presented in this chapter, eye care professionals, sports officials, and participants will significantly reduce the risk of eye injuries without changing the essential nature or appeal of sports.|
|Without knowledge of the incidence and severity of sports-related
eye injuries, it would be difficult to attempt injury reduction since
there would be no way to determine whether preventive methods were indicated
or if they had an adverse or beneficial effect. A major potential
pitfall in studying epidemiologic data is that the data obtained
may reflect only the risk of a sport and not the benefits that may or
may not justify the risk.9 The objective is to reduce preventable eye injuries to the minimum consistent
with retaining the benefits: the fun and appeal that draw participants
into the sport. It is possible to achieve this goal most of the
time after the incidence and mechanism of eye injuries are ascertained
and a committee representing all concerned with the sport—athletes, coaches, officials, and the medical profession—meets to
solve the problem.|
In 1991, the National Institutes of Health Conference on Surveillance Strategies for Sports Injuries in Youth recommended the creation of a universal database,10 yet a decade later there still is no system that records all sports eye injuries with a numerator (injuries, injury details, and use of protective equipment) and a denominator (participants, exposures, player skill) from which the injury risk to both the individual and society can be calculated. In the absence of such a system, the incidence of sports eye injuries and the effect of injury prevention programs must be approached either from studies that emphasize the risk to society and attempt to measure the total number and severity of injuries in a given population or from the study of a small controlled population from which risks to the individual can be estimated.
It is essential to realize that injuries are not accidents. Instead, they have definite patterns and distinct nonrandom characteristics.11,12 By carefully evaluating the underlying mechanisms, patterns, and rates of injury in a given sport, it is possible to design and implement extremely effective preventive programs.
RISK TO SOCIETY
Although incomplete, the data show that eye trauma is a major public health problem,13–15 of which sports comprise a significant proportion.16 Sports and recreation accounted for 10% of all hospital-treated eye injuries in Dane County, Wisconsin in 197917 and 65% of all eye injuries to children in Israel from 1981 to 1983.18 Sports-related injuries were responsible for 60% of hyphemas and 10% of open-globe injuries in 3184 patients seen in the Massachusetts Eye and Ear Emergency Room over a 6-month period.19 Approximately one-fourth of all trauma admissions to the Manchester Royal Eye Hospital in 1987 and one-sixth of all trauma admissions to the Wills Eye Hospital over a 3-year period were secondary to sports-related injuries.20–22 Sports-related injuries (BB gun, golf, basketball) resulted in four enucleations in Olmstead County, Minnesota, between 1956 and 1988.23 BB gun and other sports injuries are common in children.22,24 In 11 to 15-year-old children, sports and recreational activities accounted for 27% of all eye injuries.25 Injuries result in visual acuity of less than 20/200 secondary to the development of amblyopia in the injured eye in over 40% of children injured before the age of 10.26 The vast majority of injured players were not wearing any form of protection at the time of injury.4,27,28
Regional injury data often reflect the local popularity of a sport and do not necessarily reflect the risk to an individual participant. Playing with bow and arrow and gilli-danda accounted for a majority of the sport injuries (47.2%) in northwest India,29 but neither of these activities appear in the data from the United States and Canada. From a societal perspective, the focus of prevention must vary from one location to another. However, basic mechanisms of injury are often similar for different sports.
There are several sources of injury data, some more useful than others:
The National Safety Council system and state data collecting systems have been of little value in the study of sports-related eye injuries because their data are difficult to obtain and are often inconsistent. Gathering of statewide data30 from hospital records is often impeded by the method of hospital record keeping, which often fails to identify the cause of injury or the circumstances surrounding the injury.
The National Athletic Injury/Illness Reporting System (NAIRS) has, in the past, obtained useful data by following injury rates in participating schools.31 However, the data are no longer available.
In 1985, The Centers for Disease Control (CDC) consolidated its nonoccupational injury research efforts into the Division of Injury, Epidemiology, and Control. The reports on eye injuries thus far have not been detailed enough for use in monitoring sports-related eye injuries.
The National Electronic Injury Surveillance System (NEISS) was established under a 1973 congressional mandate that established the U.S. Consumer Product Safety Commission (CPSC) to protect the public from unreasonable risks of injury and death associated with consumer products.32 NEISS is the core of CPSC's Bureau of Epidemiology, and currently comprises 101 hospital emergency departments that make up a stratified sample of all hospital emergency departments throughout the United States and its territories. NEISS data—categorized by body part, product, and activity—are good for estimating the total social cost of injuries that affect large segments of the population. NEISS is limited because only emergency department visits related to injuries caused by products are recorded as the basis for projections of a national probability. Because specialty eye hospitals and private ophthalmologists' offices, where most of the sports-related eye injuries are seen, are not included in the sample, NEISS data must be viewed with caution. For example, the extreme eye injury hazard of boxing is not apparent from NEISS data. Yet national trends (e.g. the large number of basketball and baseball eye injuries) are often apparent from these data (Table 1, and Appendix 1).
TABLE 1. Sports and Recreational Eye Injuries, Calendar
Year 1998 NEISS Estimates by Age Group and Percentage of Total
APPENDIX 1. NEISS sports and recreational eye injury
The National Eye Trauma System (NETS) is a consortium of approximately 50 regional eye trauma centers that prospectively gathers information on the etiology, treatment, and final results of open-globe eye injuries. However, most sports-related eye injuries are caused by blunt objects and do not penetrate, perforate, or rupture the globe, and thus are not recorded. Despite the fact that the consortium misses most sports-related injuries, it is astounding that 14.1% of all injuries in the NETS database are from sports. As expected, injuries caused by projectiles (38.1% of reported recreational injuries were due to BB/air guns) lead the NETS list of perforating injuries due to sports.2,33
The United States Eye Injury Registry (USEIR) was formed in December 1988, modeled on the Eye Injury Registry of Alabama, which began in 1982. USEIR, now a federation of 40 state registries and the United States Military Eye Injury Registry, collects and disseminates comprehensive data on the occurrence of serious (involving permanent or significant structural or functional changes to the eye) ocular injuries. USEIR provides data on a broad spectrum of eye injuries, including blunt trauma and chemical injuries that are frequently seen only in ophthalmologists' offices. Because of underreporting by ophthalmologists, USEIR captures approximately 0.3% of sports and recreational eye injuries (approximately 400,000 in NEISS and 1300 in USEIR over 10 years).34 Table 2 is a summary of USEIR sports eye injury data.
TABLE 2. USEIR Sports and Recreation Injuries December
1988 to September 1999
National data collected by the cooperating ophthalmologists of the Canadian Ophthalmological Society (COS) (Appendix 2)4 provides a useful national database available for following trends in sports-related injury and the results of intervention with rule changes or protective devices. The COS, which freely shares its data, has maintained the longest term prospective database of sports-related eye injuries and has played a vital role in the prevention of these injuries. Because the COS system—like USEIR—depends on the voluntary reporting of cases by individual ophthalmologists, the reported cases are an indeterminate small percentage of the actual injuries.
SGMA International compiles the most reliable estimates of sports participation in the United States.35 Data for specific sports are included in the discussions of individual sports. SGMA International details participation trends in 103 fitness, sports, outdoor, and recreational activities, based on a nationally representative sample of 14,276 adults and children. Sports participation falls into approximately three fairly equal groups: 86.1 million participate frequently; 83.6 million participate occasionally; 81.3 million do not participate. Combining these data with the data of NEISS gives a somewhat better perspective. The fact that soccer participants increased from 2.3 million in 1990 to 4.3 million in 2001 suggests that the increase in total soccer eye injuries (Appendix 1) may be due to an increase in players at risk rather than a change in incidence.
RISK TO THE INDIVIDUAL
More important to the athlete than the injury statistics noted above, is the risk of a specific sport to an individual participant. Despite the lack of an ideal data collecting system, it is possible to ascertain the eye injury potential of various specific sports and follow the re-sults of intervention, with rules changes or protective equipment, by means of limited, specifically designed studies.36
The National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) was developed in 1982 to provide current and reliable data on injury trends in collegiate sports. At first, only football data were collected, but the ISS has expanded to include wrestling (men's); basketball, soccer, lacrosse, and gymnastics (men's and women's); field hockey, volleyball, and softball (women's). Participation is limited to the 977 NCAA member institutions with ISS participants picked at random to have a minimum 10% representation of each NCAA division (I, II, and III). Data from the NCAA do not record every injury, but are a sampling that is representative of the total population of NCAA institutions sponsoring a particular sport. ISS gives the eye injury rate per 1000 exposures,37 but it is difficult for many to judge risk unless the NCAA data are put into more understandable terms. The NCAA incidence figures can be multiplied by the average exposure (number of games and practices) to give an easily understood risk to the individual per season and per school career—8 years high school and college (Table 3).
Open-globe injuries: softball (4); football (4); baseball (2); men's basketball (1)
Mean of 5 years (1997–2002) except for women's ice hockey (2 years: 2000–2002)
Based on NCAA data, probability calculation advice courtesy of Randy Dick and Preston Fiske.
It has been more than 20 years since the National Society to Prevent Blindness (NSPB, now called Prevent Blindness America) made recommendations that sports-related eye injury data gathering fulfill the following criteria: (1) to permit population-based comparisons involving a known denominator; (2) to record demographic data and details of the injury at the time of presentation to the medical facility; (3) to record the diagnosis of the physician at the time of examination; and (4) to record the final outcome of the injury.16 As can be seen from the data gathering systems presented, data collection has a long way to go to realize these recommendations.
The analysis of input from many reporting sectors is needed to comprehend the magnitude of sports injuries, the need for protective programs, and the effectiveness of implemented programs. From the preceding and the data to follow, it is possible to approximate the eye injury risk to the unprotected participant from selected sports (Table 4).
*Javelin and discus have a small potential for injury that is preventable with good field supervision.
|ECONOMICS OF SPORTS EYE INJURIES|
|The social cost of eye trauma, the most common ophthalmic indication for
hospitalization, is enormous. National projections estimate annual U.S. hospital
charges of $175 million to $200 million for 227,000 eye
trauma hospital days.38 Eye injuries seen in 6 months in one emergency department are responsible
for direct and indirect costs totaling $5 million and a loss
of 60 work-years.19 The average societal cost for an eye injury to a child under the age of 15 playing
basketball is $3,996.39 It is estimated that of the 1.6 to 2.4 million Americans who sustain eye
injuries each year, 40,000 will be legally blinded in the injured eye. About
one third of these injuries result from sports.40 Because essentially all sports-related eye injuries are preventable, the
potential economic savings resulting from the prevention of
these injuries is great. There is no question that prevention of traumatic
sports-related eye injuries is cost effective.41 In 1980 dollars, the hockey face protector saves society $10 million
a year by preventing approximately 70,000 eye and face injuries
in 1.2 million protected players.3|
Total expenditures for preventive health care amounted to under 2.5% of total health care expenditures with less than 0.5% spent on health education.42 Despite the fact that injuries are one of the leading causes of physician and hospital visits, the amount allotted by Congress and the National Institutes of Health (NIH) for trauma research is less than 1% of the money allotted for cancer and heart disease.11
|MECHANISMS OF SPORTS EYE INJURIES|
|The analysis of trauma is commonly expressed in International System of
Units (SI), which are the worldwide standard.43 Because it is hard for many of us to visualize what some SI units actually
measure (Is it dangerous to collide with a football player who
weighs 200 N at 5 m/s?) more understandable units, such
as miles per hour (mph) will be used when appropriate. It is
easier for most of us to grasp the speed of a baseball when the velocity
is expressed as 75 mph rather than as 33.53 m/s.|
The severity of an eye injury is correlated with the total impact force, expressed in newtons (N), and the impact force onset rate, expressed in newtons per millisecond (N/ms), and the kinetic energy, expressed in joules (J) of an impacting object. There is an eye-injury progression from chamber angle damage to peripheral vitreoretinal damage to ruptured globe as the force increases and the time to maximum force decreases.44 If we slow the velocity of a BB (0.345 g) to 29 mph (13 m/s; 43 ft/s), the energy will be beneath the kinetic energy of 0.03 J required for an ocular contusion and there will be no eye injury. However, when fired in the horizontal direction from a height of 5 feet, the BB would travel only 24 feet.45 As the BB velocity increases, the injuries get more severe: 62.3 m/s (205 ft/s) will result in injury at the vitreous base and retinal tear; 72.0 m/s (236 ft/s) penetrates the globe; 124 m/s (408 ft/s) penetrates skin, bone, and moderate tissue.45,46
Test devices47 and mathematical models44 have been devised for the laboratory testing of various products, such as toys, to assess the potential for eye injury. The force onset rate needed to produce clinically detectable contusion injury by a blunt object is approximately 750 N/ms. Some toy dart guns (896 N/ms) that propel suction cups exceed this level, while most toy ping-pong ball shooters (428 N/ms) do not.48 Computer modeling using finite element analysis has led to better analysis and understanding of the mechanisms of eye injury (Fig. 1).49–52
Many protectors (such a football helmets) for sports and some protective eyewear53 prevent or reduce injury by decreasing the force onset rate and the peak force by spreading the total force over time. However, the injury as related to force onset rate only applies total forces in a limited range, which has not yet been determined.
Sports eye injuries can be classified in accordance with the Birmingham Eye Trauma Terminology (BETT) in which all terms relate to the whole eyeball as the tissue of reference.54 Injuries may be:
The eyewall (the cornea and the sclera) can be modeled as the union of two thin-walled (approximate 0.5 mm wall thickness) spheres (radii, 8 mm and 12 mm) with the centers 5 mm apart.55 At the junction of the optic nerve sheath, which may be represented by a cylinder (radius 2 mm), the larger (scleral) sphere is perforated by multiple openings, the lamina cribrosa.56 However, the eyewall is not of uniform thickness,57 is significantly thinner in myopic eyes,58 and becomes less elastic with age.59 The eyewall tends to rupture in three specific locations: (1) where the radius of curvature changes at the limbus, (2) where the sclera is the thinnest, near the equator behind the ocular muscles, and (3) where the sclera is perforated at the lamina cribrosa.55
Even with the best surgical techniques, approximately 50% of children with open-globe injuries recover good visual acuity.60
Ragged rupture of the globe secondary to injury by a blunt object significantly reduces the likelihood of recovery of useful vision.13,61–64 Only 7 of 13 ruptured eyes regained counting fingers or better vision.65 Rupture of the globe occurs when the intraocular pressure is greatly elevated or when a blunt external force is applied quickly to the eye. The energy required to rupture the eye varies with the dimensions and the properties of the impacting object (Table 5). Figure 2 shows a matched pair of cadaver eyes impacted with baseballs that had similar physical properties except for the ball hardness. Impact with a major league baseball (143.9 g) at 55 mph ruptures the globe at 3 ms. Impact with a softer ball (146.5 g) at 74 mph does not rupture the globe, despite the fact that the softer ball delivered more energy (80.2 J) than did the harder ball (43.5 J).66 The harder baseball causes extreme flattening of the globe (2 ms) immediately followed by rupture at the limbus (3 ms). After the ball has totally rebounded from the eye and orbit, the ocular contents continue to be extruded by the retained energy in the globe. When compared to the softer baseball that does not rupture the globe, it is apparent that the harder ball delivers energy faster, deforms the eye more, and rebounds faster. The softer ball has a lower peak force and slower force onset rate (peak force 3208 N; onset rate of 2686 N/ms) than the harder ball (peak force 3768 N; onset rate of 3486 N/ms). It appears that the slower application of force allows the globe to retract into the orbit and undergo less compression than when the force is applied faster
TABLE 5. Globe Rupture: Correlation Among: Intraocular Pressure, Object Hardness, Size, and
*Approximate averages. Rupture of individual eyes varies.
The sports that cause ruptured globes to unprotected players typically use a stick with a blade end that fits into the orbit (hockey, field hockey, golf, polo), a small soft fast projectile (BB, paintball), a soft or hard ball that deeply penetrates the orbit (squash, golf), a hard projectile that partially enters the orbit with great force (hockey, baseball, softball, cricket, field hockey, polo), or a one in which there is the potential of contact with a body part that enters the orbit with force (basketball, football, soccer, rugby).
Prior Surgery or Eye Disease.
It is apparent that an eye that would have had a closed-globe injury may sustain an open-globe injury (rupture) because surgery has weakened the eyewall.67 Deeper, longer incisions, especially in the cornea, permanently weaken the eyewall and predispose the eye to an open-globe injury. Table 6 lists the approximate risk from various surgical procedures. All patients who have had surgical procedures that weaken the eyewall should be advised that eye protection is essential when there is the probability of impact.68 The concept that a ruptured globe is a safety valve that prevents contusion injuries cannot be supported by injury data (Fig. 3).
*Late traumatic dehiscence of corneal flap is a potential problem
In which the same agent causes an entry and an exit wound, are usually due to a high speed projectile (air rifle/BB, firearm, shrapnel) or a slower sharp projectile (shattered eyewear, fishhook, tip of ski pole, arrow, dart). There is little data on the energy required to cause perforating injuries, which are similar to but more severe than penetrating injuries.
The same agents that cause perforating injuries result in penetrating injuries or intraocular foreign bodies when there is sufficient energy to penetrate the eyewall, but not enough energy to exit the globe. A knife-edged missile is in a class by itself for ease of penetration. The mechanical advantage of the cutting edge is exerted until the hole it makes is the full diameter of the missile. A 20-gauge knife-edged missile penetrates the globe with a momentum of 17 mg · m/s69 compared to the momentum of 24,840 mg · m/s as the nopenetration value for the BB.46
The energy present in many sports is capable of causing severe eye injury and often exceeds the capacity of ordinary eyewear to withstand the impact and protect the eye. Frequently, the lacerating instrument is a fragment of the athlete's own spectacle lens. Thus, the wrong eyeglasses can convert blunt trauma into penetrating ocular injury and permanent visual impairment.70–72 Globe laceration caused by spectacle lens shatter has a poor prognosis and is underestimated. Keeney73 found 491 cases of spectacle glass injuries resulting in 369 ocular injuries and 37 lost eyes. Over a 1-year period, 3.6% of 446 cases of penetrating ocular injury in Canada were the result of shattered spectacle lenses—40% of the shattered lens injuries were to adult male amateur athletes.74 Between 1978 and 1986, at least 21 racket sport players sustained serious ocular injuries when their prescription glasses (hardened glass or plastic, but not polycarbonate or Trivex) shattered.75,76 Of 298 eyes injured by shattered spectacle lenses in a nonindustrial setting, 157 suffered significant damage and 27 were lost. Sports accounted for 53 (17.8%) and BBs for 16 (5.4%) of the shattered eyeglasses.77 Sixteen of 635 work-related penetrating eye injuries resulted from shattered street-wear spectacle lenses.78 One of the two penetrating ski eye injuries reported to NETS was the result of dress spectacles shattering on impact from the handle of a ski pole. Two soccer players had significant structural changes to their lids and globes when the ball shattered street-wear glasses.79 A homemade “potato-gun” caused a sight-threatening corneal laceration when the spectacle lens worn by a 14-year-old boy shattered.80
Because approximately half of the population wears eyeglasses,81 the prescription of the appropriate spectacle lens (Fig. 4) can protect a huge segment of the population, whereas an incorrect recommendation by the practitioner exposes the patient to the risk of a shattered lens, a perforated globe, and the good chance of permanent disability.82
Other than shattered eyewear, the principle causes of intraocular foreign bodies seen in sports are BBs, shotgun pellets, and fishhooks.
Closed Globe Injuries
Nonpenetrating trauma results in a wide variety of tissue damage involving chamber angle deformities and injury to the retina, choroid, vitreous, and lens. The injury to the eye depends on the maximum force, the time to the maximum force, the area of contact, and the properties of the impacting object. The expansion of the eyeball perpendicular to the direction of impact, has been proposed as the major cause of the contusion injuries that result from blunt trauma (Figs. 1 and 2). When a small, high-velocity object (such as a BB) hits the eye on the cornea, the entire eye deforms, and the weakest portion of the retina (upper nasal) often fails.46,83 When a large object (such as a soccer ball) hits the eye (especially in younger players where the orbital rims are less developed) more energy is directly transmitted to the exposed temporal retina while the nasal retina is protected by the nose. A suction component84 (Fig. 5, Table 7) most likely adds to the distortion of the globe anatomy that causes stresses resulting in tearing of structures in the anterior85 and posterior86 segments of the eye. This extreme distortion in the anatomy results in tearing of internal ocular structures (sphincter pupillae, peripheral edge of the iris, anterior ciliary body, attachment of the ciliary body to the scleral spur, trabecular meshwork, zonules, attachment of the retina to the ora serrata, and Bruch's membrane) that are resistant to stretching when the globe undergoes the deformations induced by the force of the impact.85,87 Because there frequently is a long interval between ocular contusion and the appearance of retinal detachment, and retinal breaks are formed at the time of injury, it is essential to examine the peripheral retina of all eyes that have had a contusion injury.88 Blunt trauma may cause transient high myopia by anterior shift of the lens-iris diaphragm and thickening of the crystalline lens.89 Hyphema may be caused by the shock wave of a pure blast injury.90
A blow by a blunt object smaller than the orbital opening, such as a BB, paintball, golf ball, finger, or hockey stick, will transmit great forces to the globe. To produce eye injury, less energy is required with high-speed and small-mass missiles (BB shot) than with low-speed and large–mass missiles (soccer ball).
A blow by a blunt object larger than the bony opening, such as a tennis ball, elbow, or fist, has some of the energy absorbed by the surrounding bones, soft tissues, and orbital floor, which may fracture. There is a high incidence of internal ocular injury in these cases.91 The concept that an impacting object with radius of curvature above 2 inches (4-inch diameter) rarely causes eye injury because the ball delivers most of its energy to the orbital rims92 is incorrect. Large balls (such as a soccer ball) and boxing gloves deform significantly on impact, allowing a small “knuckle” of the ball or glove, with a smaller radius of curvature, to enter the orbit and impact the globe. It is only by experiments utilizing high-speed photography, coupled with injury data, that the true mechanism of injury can be elicited and appropriate protective devices designed.
The primary lamellar laceration potential from sports is the dislocation of a laser in situ keratomileusis (LASIK) flap. All patients who have had LASIK should be warned of this potential complication93–98 and be advised of appropriate protection, lest their flap be dislocated by a finger while playing basketball99 or by a tree branch.100
Injuries to Higher Visual Pathways
Blows to the skull with direct or indirect injury to the visual pathways may result in permanent or temporary visual loss.101–108 The huge forces required to produce these injuries can be encountered in many sports (e.g., collision sports, skiing, cycling, motor sports).109–112 With high-energy loads, eye protection must be considered as part of an integrated eye/face/head/brain protection system.
|PRINCIPLES OF PREVENTING SPORTS-RELATED EYE INJURIES|
|There is a natural sequence of events that will decrease the eye-injury
risk of a sport to the individual player:|
DISTRIBUTION OF FORCES
Forces are best dissipated if they are transmitted over a wide area and the duration of time over which the force is allowed to act is lengthened.113 If possible, the best area for distribution of forces when one tries to protect the eyes is the frontal bones. These bones are the sturdiest about the orbit and have the tendency to transmit energy into the mass of the face by the lateral orbital margins.117–119
Whenever a large force is transmitted anywhere on the head the prime consideration must be the ultimate dissipation of this force as it relates to the brain. It is senseless to protect an eye if in so doing the damaging forces are transmitted directly to the brain. All protective devices for the head and face thus require two areas of consideration: (1) is the primary area of concern (e.g., eye, face, teeth) protected? and (2) is the transmission of forces such that there is no added risk to the brain? In collision sports such as hockey or football, this result is best achieved by mounting a face protector on a properly designed helmet. In this manner, the desirable goal of total head (not isolated eye, face, teeth, etc.) protection is achieved. Helmet design must be monitored by comparing predicted force114,120 with actual measurements of injury to real players in action.121
Sports with less energy potential require less protection. A squash ball has little potential for injuring the brain; therefore, attention need only be directed toward protecting the eye. In this case, one might consider it acceptable to transmit the forces to the frontal bone (best) or even less desirable areas (the bridge of the nose, the lateral or infraorbital rims) and still achieve good eye protection. One could accept a cut on the cheek, a broken nose, or even a fracture of the zygoma as far preferable to the potential loss of the eye.
The best sports standards are performance standards that specify how a protector must perform (e.g., visual fields, impact resistance, distribution of forces) rather than design standards that contain certain design elements that may or may not relate to performance. By and large, design standards are unnecessarily restrictive, tend to stifle the introduction of better, more innovative protector designs, and are more likely to encounter antitrust problems than performance standards.122
It is clear to those who write standards that one cannot tell how a protector will perform until it is tested under game conditions or conditions that approximate game conditions.123 If those who write standards and test protectors cannot tell how a protector will perform until the protector is tested, it is obvious that the untrained consumer will be unable to determine which products will provide adequate protection with minimal impact on performance by inspection in the retail shop. Severe eye injuries in sports can be prevented by writing performance standards that specify the protector's energy attenuation and visual requirements followed by certification of the protective equipment produced by manufacturers.124 Sports regulatory bodies must mandate the use of equipment that passes the standard requirements, and governing bodies must legislate against uncertified products gaining access to the marketplace.125
Test requirements of relevant eyewear standards are listed in Table 8.
American Society for Testing and Materials International
The majority of sports eyewear standards writing in the United States falls under the jurisdiction of the American Society for Testing and Materials (ASTM). The largest of the approximately 400 standards-writing bodies in the United States, ASTM is neither a government nor a manufacturer's organization but a nonprofit corporation organized in 1898 for development of voluntary standards arrived at by consensus, with strict guidelines for due process, among all interested parties.126,127
ASTM committee F–8 on sports safety standards and sports safety was formed in 1968 to address the sharp increase in head and neck injuries in football.128 ASTM F–8 now has subcommittees that write standards for many sports, including gymnastics, golf, archery, wrestling, fencing, trampolines, fitness products, racket sports, hockey, and baseball, as well as groups concerned with the more general problems of medical aspects and biomechanics, playing surfaces, headwear, footwear, padding, statistics, warning labels and signs, the female athlete, and eye safety.
Standards are designed to be revised as experience is gained. No matter how well the protector performs on paper or in the testing laboratory, it is only the use by thousands of players and continued injury monitoring that prove the protective value or demonstrate the failures of a particular design. For this reason, the ASTM mandates review of every published standard every 5 years. Other standards organizations (e.g., Canadian Standards Association [CSA],129 American National Standards Institute [ANSI], Deutsches Institut fur Normung, International Organization for Standardization) operate under various bylaws.
At present, ASTM has completed the following standards for sports eye protectors:
American National Standards Institute
The American National Standards Institute (ANSI) writes standards for protective eyewear in the United States with the exception of sports eyewear. It is the central body responsible for the identification of a single, consistent set of voluntary standards called American National Standards, and is the U.S. member of international standards organizations. ANSI follows the principles of openness, due process, and a consensus of those directly and materially affected by the standards.
ANSI standards for eyewear are:
The ANSI Z80 standards are for dress eyewear, also called street-wear spectacles. The test requirements are minimal and geared to the desire for a diversity of styles in fashion eyewear. Street-wear spectacles are not appropriate for work or sports with impact potential. Impact-resistant polycarbonate or Trivex lenses should be used for dress eyewear. Street-wear frames are often fragile and have poor lens retention properties. Significant eye injuries have resulted from frame failure. Yet a street-wear frame with an impact resistant polycarbonate or Trivex lens does give protection from low impact injuries, such as a fishhook or a snapping twig.
The ANSI Z87.1 Industrial eye protectors are not satisfactory for sports for which there are ASTM standard specifications (Fig. 6). Yet ANSI Z87+ eyewear, designed to stop small, high-velocity fragments, is an excellent choice for moderate impact sunglasses and eyewear for shooting, fishing, cycling, and other activities that involve the potential of impact with a small fragment.
Department of Defense
Military eyewear will be coordinated under a single umbrella program called the Military Eye Protection System (MEPS; http://www.dod.mil/) in which testing is done with fragment-simulating (T–37) projectiles (Fig. 7) either 0.22-caliber, 17 grain (1.1 g) at 168 m/s (550 ft/s) or 0.15-caliber, 5.8 grain (376 mg) at 195 m/s (640 ft/s). Sun, wind, and dust goggles (MIL-V–43511); ballistic/laser protective spectacles (MIL-PRF–44366B); and special protective eyewear, cylindrical system with interchangeable lenses (MIL-PRF–31013) standards assure eye protection from the majority of fragments anticipated in military combat. Although this eyewear has not been tested for sports use, it would provide excellent protection for the hunting and shooting sports, but not for sports for which specific ASTM standards apply (such as paintball, hockey, and sports covered under ASTM F803).
National Operating Committee on Standards for Athletic Equipment
The National Operating Committee on Standards for Athletic Equipment (NOCSAE; http://www.nocsae.org) has standards for baseball, football, and lacrosse helmets; baseballs and softballs; and face shields for football and men's lacrosse.
Current NOCSAE standards include:
Headforms are necessary for testing and development. Headforms may be impacted without injury and give consistent results. Choosing the proper headform is essential to any protector design or testing. The anthropomorphic features, hardness, and energy-absorbing characteristics all affect test results. Comparison of the results on the test headform with those actually achieved on the human head are essentia1.131,132 The Canadian headforms, which are based on actual physical and radiologic measurements of thousands of heads,133 are better proportioned for eyewear testing and design than the commonly used U.S. head forms (Alderson 5, 50, and 95 percentile), which are based on projections made from measuring a sample of military men. NOCSAE revised its test forms with anthromorphic measurements based on CSA data.
|EQUIPMENT CERTIFICATION COUNCILS|
|Protectors are often certified, giving the user the assurance that the
protector will afford reasonable protection. A Sports Equipment Certification
Council is composed of coaches, participants, scientists, physicians, manufacturers, and
administrators. Its purpose is to seek out
and select codes and standards, including test methods and procedures, for equipment used in athletic, sporting, recreational, and
leisure time activity. In addition, the council identifies and publishes
all factors associated with safety, whether it for protective
equipment, playing surfaces, rules, attitudes, officiating, training, conditioning, and
administration.134 The Council will usually have a seal (Fig. 8) that manufacturers affix to a protective device that is assurance
to the consumer that a product meets the specifications of a performance
standard (Fig. 9).|
HOCKEY EQUIPMENT CERTIFICATION COUNCIL
The Hockey Equipment Certification Council (HECC) (http://www.hecc.net) is an independent, nonprofit organization that was established in 1978 through the joint efforts of the Amateur Hockey Association of the United States and a number of interested volunteers. HECC certifies ice hockey equipment, including helmets and face shields; selects codes and standards to certify playing equipment and facilities; monitors the effectiveness of its certification program; and promotes research pertaining to the prevention and reduction of ice hockey injuries. HECC is extremely effective in fulfilling its mandate of reducing injuries in hockey.
PROTECTIVE EYEWEAR CERTIFICATION COUNCIL
The Protective Eyewear Certification Council (PECC) (http://www.protecteyes.org) certifies protectors complying with ASTM standards (except for ice hockey). A testing laboratory must be able to provide evidence of the successful completion of the American Association for Laboratory Accreditation (A2LA; http://www.a2la2.net/) evaluation process to perform the tests that are specified in the standards.
CANADIAN STANDARDS ASSOCIATION
The Canadian Standards Association (CSA) (http://www.csa.ca) certifies products complying with the Canadian racquet sport and ice hockey standards, which are similar to the ASTM standards.
|OBSOLESCENSE IN PROTECTIVE EQUIPMENT|
|Protective equipment is obsolete when it no longer provides adequate protection, cannot be purchased under normal circumstances, is no longer in the desired style, is unreconditioned “hand-me-down” equipment, or is worn out, broken, or ill-fitting.134 As injury data result in standard modification, certification councils must publish a list of equipment that has become obsolete by newer advances, and this obsolete equipment must be discarded.|
|GUIDELINES FOR SPORTS PARTICIPATION|
|The American Academy of Pediatrics classifies sports into three main categories (contact/collision, limited contact/impact, and noncontact)135–137 and suggests that some sports are contraindicated for the one-eyed
participant. The traditional contraindications to athletic participation
are more appropriate to the systemic, musculoskeletal, cardiac, respiratory, paired-organ, and central nervous systems than to
the eye. Whereas musculoskeletal injuries and cerebral concussions are
inevitable in contact/collision sports (such as rodeo) and
are rare in noncontact sports (such as golf), eye injuries
may be more common and severe in the “safer” sport. The recommendations
of the American Academy of Pediatrics may be considered
overrestrictive as society becomes more aware of the civil rights of athletes
and the need to allow the handicapped to participate in sports.138–140 It is apparent that more realistic guidelines for participation in sports
by persons with various ocular handicaps and ocular diseases could
be devised. Although such a list is dependent on reliable injury data
that are not available at this time, there was sufficient information
for the International Federation of Sports Medicine to release a position
statement on eye injuries and eye protection in sports, which should
help reduce eye injuries worldwide.141|
THE ONE-EYED ATHLETE
Severe eye injury to a child can result in posttraumatic stress disorder, even if the vision is restored to reasonable levels after surgery.142 The emotional, psychological, and legal impacts of severe eye injuries are often neglected but attention to them is essential in the management of all patients who have suffered severe injury, especially that involving the loss of an eye.143,144 The risk of becoming blind is markedly higher for the amblyopic patient (1.75 ± 0.30 per 1000) than for the general population (0.11 per 1000 for children, 0.66 per 1000 for adults). Trauma (work, sports, violence, accidents) causes over 50% of the resultant blindness.145
How can we define one-eyed? For the purpose of recommending extra safety precautions, a person is functionally one-eyed when loss of the better eye would result in a significant change in lifestyle because of the poor vision in the remaining eye.146 A person certainly should be considered functionally one-eyed if his or her best-corrected vision in the involved eye is 20/200 or less, with the other eye found normal by an ophthalmologist. On the other hand, most of us would function fairly well with 20/40 or better vision in the remaining eye. More difficult is advising patients with between 20/40 and 20/200 best corrected vision in the affected eye. The loss of the ability to drive a vehicle legally in most states would be a handicap to most persons. The inability to drive would significantly interfere with the jobs available to a youngster when he or she is older, and studies would be more difficult throughout the school years. Therefore, a child should be considered functionally one-eyed when the best-corrected vision in the poorer eye is less than 20/40, and an adult is functionally one-eyed if he or she believes the level of vision in the poorer eye would interfere with life or livelihood if the better eye were lost.147 Functionally one-eyed athletes (and their parents in the case of minors) must be well informed of the potential long-term consequences if the better eye were lost. They should also be informed of the risks of injury (without and with various eye protectors) and the possibility of repair of injuries typically seen with the sport in question.
It is only by full discussion of the potential serious long-term consequences of injury to the better eye that the ophthalmologist, the athlete, and the parents can agree on the wisdom of participation in a particular sport as well as the level of protection necessary for the better eye. The most effective protection is possible only when the athlete understands the risks and is anxious to cooperate in the effort to protect the eyes while still allowing participation and enjoyment of the preferred sport. Having the athlete wear an occluder over the better eye for several days will allow him or her to evaluate the ability to function with the poorer eye better. Usually, if the athlete is sincere and honest with himself or herself, it is fairly easy to reach agreement among the athlete, parents, ophthalmologist, and sports officials as to whether the athlete is functionally one-eyed.
As protective devices improve and effective sports eye protectors are developed, more and more sports become quite safe even for the one-eyed athlete.148 The division of sports into contact/collision (boxing, field hockey, football, ice hockey, lacrosse, martial arts, rodeo, soccer, wrestling); limited contact/impact (baseball, basketball, bicycling, diving, high jump, pole vault, gymnastics, horseback riding, ice and roller skating; cross country, downhill, and water skiing; softball, squash, handball, volleyball), strenuous noncontact (aerobic dancing, crew, fencing, discus, javelin, shot put, running, swimming, tennis, track, weight lifting), moderately strenuous noncontact (badminton, curling, table tennis) and nonstrenuous noncontact (archery, golf, riflery)149 tells little of the risk of eye injury. From an eye injury perspective, it is far more dangerous to play badminton (moderately strenuous noncontact) without an eye protector than to play ice hockey (contact/collision) with a full face mask.
Any banning of athletic participation in certain sports should be based on guidelines using an experiential framework rather than tradition or anecdote.150 The athlete deserves a true discussion of the risk of eye injury involved in a chosen sport. The outright ban, by some schools, of the one-eyed from participation in collision and contact sports, while the one-eyed students are permitted to play more dangerous (to the remaining eye) sports, such as tennis, is not prudent and should be reevaluated. Unless the athlete is especially gifted in a particular sport, or has psychological reasons to participate in a chosen sport, a safer sport (e.g., track and field, gymnastics) should be encouraged and will usually be chosen. The American Academy of Pediatrics recommendations now take into account that with adequate protection, the one-eyed may participate in most sports.149 The medical/school committee should specify that the one-eyed athlete follow the safety guidelines presented in this text or modified in the future.
At this time, the only sports absolutely contraindicated for the functionally one-eyed are boxing and full-contact martial arts because the risk of serious injury is very high and there is no known effective eye protector. Wrestling and the noncontact martial arts, while having a lower incidence of eye injury, also do not have effective eye protection available and should be strongly discouraged for the functionally one-eyed and banned for the monocular athlete. If the player, parents, and possibly their lawyers are persistent and insistent after an informative discussion, they should be required to sign appropriate waivers as dictated by the school committee. The waiver has a dual purpose: it helps ensure that the athlete will wear appropriate protective devices for practices and games, and it often affords the only possible legal protection for school committees and members of sports-medical committees faced with the dilemma of the one-eyed athlete who insists (or whose parents insist) he or she play a sport with high risk of eye injury, such as wrestling, for which there is no adequate known protection. The best medical advice says that the functionally one-eyed athlete should not, but it seems that there may be confusion in the law.151 The Massachusetts law reads, “The health and safety of each student must be paramount in every phase of the instructional physical education program,” and also “Each school shall provide equal opportunity for physical education for all students.” 52 Federal law states, “Students who can participate in regular physical education programs for all or some aspects of physical education must be placed in such programs.”153 The physician becomes hard put to prove that he or she is not discriminating against the handicapped by excluding the one-eyed student from some sports.154
From a performance standpoint, the one-eyed athlete can usually function quite well in most sports, adding very little risk to cause other injuries because of the monocular condition. Ocularists (makers of prosthetic eyes), who deal with many one-eyed people, are aware of this fact155; however, ocularists should also have expertise in available eye protection and give appropriate recommendations to the patient. The reinforcement of the protective message is very important. If the athlete is informed of the need for protection, and also given specific advice by the ophthalmologist, optometrist, optician,156 and ocularist, there is a far greater likelihood of protection compliance.
Fortunately, most sports-related eye injuries are preventable with properly designed equipment. The following is a practical guide for sports eye protection so that persons whose responsibilities involve the eye in athletics can easily determine the protective equipment they should recommend or provide.157 A protective device should prevent damaging forces from reaching the eyes by dissipating potentially harmful forces over time and area. This theory is simple enough, but the practical application can be difficult. As soon as design is begun on a protective device for a sport with an ocular hazard, many problems arise. What forces are involved in this sport? Are they high-velocity, low-mass (hockey puck); low-velocity, high-mass (player sliding into a goal post); or a combination of high-velocity and high-mass (bicycle racer collision)? Does a protector have to be designed differently for each type of force? How? Where on the head will the forces be transmitted, and how will it be done? Will the player be killed or suffer brain damage if the force is transmitted to his or her brain through the protective device, rather than being dissipated into broken facial or orbital bones as was the case before the protector? Will the protector change the form or appeal of the game? What about the design, player acceptance, expense, weight, interference with vision, product liability, and full disclosure to the consumer?
These questions cannot be answered by any one individual, because expertise at many levels and different areas of interest is required. The best way to design and build a protective device is by the development of a performance standard as discussed above.
Various kinds of eye protection and different brands of sports goggles vary significantly in the way they fit. An experienced ophthalmologist, optometrist, optician, or athletic trainer can help an athlete select appropriate protective gear that fits and looks well. The best designed protective device, if it does not appeal to the tastes of the player, will remain on the dealer's shelf. Sports programs should assist indigent athletes in the evaluation process and in obtaining protective eyewear.
Selection criteria for protective eyewear include:
For sports in which a face mask or helmet with eye protector is worn, functionally one-eyed athletes, and those with previous eye trauma or surgery for whom their ophthalmologists recommend eye protection, must also wear sports protective eyewear which conforms to the requirements of ASTM F803.
Classification of Sports Eyewear
Sports have very different eye, face, and head–brain risk, and thus require specifically designed protective equipment, The equipment can be classified into:
Sunglasses for Sports
The improper choice of sports sunglasses may be hazardous and degrade visual performance.158 Both visible and UV light can result in eye injury, which may be minimized with the use of appropriate sunglasses. It is controversial whether or not short–wavelength-visible (< 510 nm, blue) light increases the tendency to macular degeneration, but there is evidence that long-term exposure to sunlight is associated with the development of early age-related maculopathy.159–162 Exposure to UV light causes cataracts,163–167 corneal changes (climatic droplet keratopathy, pinguecula, pterygium, and acute photokeratitis),168–170 uveal melanoma,171,172 premature skin aging and sunburn,173 and skin cancers (basal cell carcinoma, squamous cell carcinoma, melanoma).172,174 Even relatively brief exposure to viewing the sun when high in the sky (zenith above 60%) may result in solar retinitis caused by photochemical injury from intense short wavelength (blue) and UV radiation.175–177 Many clinicians have the impression that herpes simplex keratitis and recurrent corneal erosion may be precipitated by exposure to sunlight.
Reflected UV light also must be considered. Fresh snow reflects approximately 80%, older snow over 50%, clean white sand approximately 30%, water 5%, and earth and grass less than 5% of the ambient UV light. Thus the greatest UV light exposure occurs at high altitude on a field of fresh snow. Mountaineers, skiers, sailors, and lifeguards, are exposed to large doses of visible and UV light, at times in situations in which there is the potential for injury from impact, in adverse conditions of high wind or dust. The inability to see well because of photokeratitis, windburn, corneal foreign bodies, or traumatic injury from shattered spectacles may be life threatening as well as eye threatening, therefore the proper choice of sunglasses is essential. Dark sunglasses permit one to be comfortable in bright light without squinting. However, one must be certain that the glasses have adequate absorption in the toxic UV and blue light ranges.178 Wearers and those observing them should be aware that the reflection from the front surface of mirrored sunglasses may result in severe sunburn to the nose unless extra protection is used.179
Sunglasses are especially important for those who have had cataract surgery. Removal of the lens of the eye exposes the retina to wavelengths above approximately 300 nm. In the 325 and 350 nm UV radiation range, the retina is approximately six times more sensitive to damage than to short–wavelength-visible radiation of 441 nm. Because untreated polymethyl methacrylate intraocular lenses (IOL) absorb UV radiation only below 300 to 320 nm,159 many IOLs classified as UV protective offer less than optimal protection.180 Also, because it is not known how long the UV filter on UV-absorbing IOLs lasts, it is prudent for all aphakic or pseudophakic athletes to wear sunglasses that absorb 99% of light below 470 to 500 nm.
Athletes who want maximum UV light protection should wear a hat with a brim, which reduces ocular exposure by half,181 and close-fitting sunglasses that absorb UV when in conditions in which they could get sunburned.182 There is considerable variability in the quality of sunglasses,183 which is of concern in children's sunglasses184 because children frequently spend more time in the sun, damage to the lens (and possibly retina) from UV is cumulative, and the crystalline lens of children transmits more short–wavelength-visible radiation and UV light to the retina than does that of the adult.159
Even with darkly tinted glasses, there is no way to predict by gross visual inspection which lenses effectively filter reasonable quantities of the near infrared light (700 to 800 nm) and near UV light (300 to 400 nm) that are not visible to the human eye. Cost, color, and lens composition are unreliable indicators of adequate filtration. In one study, 53% of glass and 11% of plastic lenses had an unfavorably high near-UV light transmission peak greater than 25%.185 Eighty percent of the amount of infrared light present in daylight is transmitted to the retina. Although the infrared light present in daylight is not toxic in itself, some believe that infrared light may contribute to damage from UV light and lower wavelengths and may contribute to ocular discomfort of fatigue. Because infrared light contains no useful visual information, it is probably wise to filter it out.159 UV light absorption is quite different for various lens materials.186
The vast majority of sunglasses sold for sports use are deficient in impact resistance. A sports sunglass should prevent rather than contribute to injury. The combination of lens and frame must prevent ocular contact by either the missile or the sunglass lens. Manufacturers should state the sports for which the sunglasses are intended. Safety requirements are the same as for protective eyewear with clear lenses. Manufacturers should be required to provide the following information, in a statement easily understood by the consumer, on all sunglasses sold for use in sports: the standard specifications to which the sunglass conforms, the percent of visible light transmitted through the lens, the percent of UV light and infrared light (wavelengths specifically stated) transmitted through the lens, additional treatments or coatings (for example, polarization) to reduce glare.
The ideal sports sunglass should have the following characteristics:
HOW DO I KNOW WHAT TO BUY, PRESCRIBE, OR DISPENSE?
It could be disastrous to buy, prescribe, or dispense what you believed was protective eyewear and then have the eyewear fail. Compounding the problem is the fact that some manufacturers make “sports” eyewear that do not conform to safety standards (see Fig. 9) and that most ophthalmologists and consumers do not know what protection standard should apply for a specific activity.
The safest way to choose an eye protector is to look for a certification seal (see Fig. 8) to assure that the protector has been tested by an accredited laboratory to a specific safety standard.
The spectacle prescription will be clear to the optician if the note, “Polycarbonate or Trivex lenses are required for children, functionally one-eyed people, and active adults is printed,” on the front of the prescription.
Although a fashion eyewear frame has little impact resistance, it is far better to have a lens that is shatter resistant in front of the eye than risk a lacerated globe from a shattered lens. It is almost certain that the eye care professional who dispenses or prescribes a spectacle lens that shatters easily will be sued if the shattered lens results in significant injury. Therefore, it is prudent to prescribe, dispense, and wear eyewear with extremely shatter resistant polycarbonate or Trivex lenses. To test the strength of these lenses, try to break them with a hammer.
Safety Recommendations on a Prescription Pad
Recommendations, printed on the reverse side of all spectacle prescriptions, should help the patient choose appropriate protective eyewear (Fig. 11).
Because contact lenses offer no protection from impact, it must be stressed to patients that protective devices, where indicated, should be worn in addition to the contact lenses. Patients who request contact lenses for sports use deserve a few minutes of discussion of injury prevention.187
Despite the fact that contrast sensitivity may be decreased with daily-wear soft lenses,188 contact lenses, especially for people with large prescriptions, do offer advantages for many sports, namely better visual field, no fogging, and staying in place with rapid motion. Lens technologies that combine the excellent visual acuity of rigid gas–permeable contact lenses with the comfort and retention characteristics of soft lenses are preferred by many athletes, especially those with astigmatism.189 Large-diameter (15.5 mm) and scleral (18–24 mm) soft lenses are available for athletes who cannot wear standard soft or rigid gas-permeable lenses because of decentration with sports activity.190–192
Many sports are played in environments that make contact lens wear more difficult because of increased exposure to water, wind, sun, dust, and dirt. The use of wraparound polycarbonate sunglasses over the contact lenses frequently allows the mountain bicycle racer to have the benefits of contact lens vision in the face of wind and debris. For sports such as ice hockey in which low humidity may be encountered, low-water, low-soiling, low-dehydrating, larger diameter, thin, soft contact lenses seem to give satisfactory results.193 Wind, dry air, UV light, and decreased oxygen at high altitude often cause punctate keratitis in skiers and mountaineers.194–196 Skiers who wear contact lenses should be encouraged to wear goggles that absorb UV light and break the wind. If contact lens wear becomes impossible, spectacles could save an otherwise ruined vacation.
|RISK OF EYE INJURY AND EFFECTIVENESS OF PROTECTIVE DEVICES FOR SPECIFIC SPORTS|
|In this section, sports are arranged roughly according to the size of the
potential impacting object. SGMA International data, estimating the
number of people who participated in selected sports activities at least
once in calendar year 2001, are presented in each subsection.35|
Small, Penetrating Projectiles
Penetrating projectiles, mostly shrapnel, shotgun pellets, BBs and air rifle pellets, fishhooks, and shattered eyewear lenses, have the highest ratio of eyes lost to injured eyes, yet are relatively easy to prevent. Streetwear spectacles with polycarbonate or Trivex lenses would stop most fishhooks. Plano industrial ANSI Z87+ eyewear gives adequate protection from BB and air gun pellets. Military eye armor will stop most small land-mine and small artillery fragments. Industrial eyewear that passes military standard specifications would stop most shotgun pellets.
There are no reliable participation data for non-target–shooting air rifle and BB guns, but there are many airguns in circulation. In the Chicago area, 6% of families that included at least one 3-year-old child and 11% of families with a boy between the ages of 10 and 14 years owned an air gun.197 Military participation varies greatly depending on combat activity. The SGMA International data for the shooting sports, archery, fishing, and darts are presented in Table 10. The main participants in the shooting sports are males in their thirties with a concentration of veterans and relatively few beginners. Only approximately 8% of the hunters were new to the sport in 2001, and nearly 60% have been involved 10 years or more. There was a relatively heavy cross-participation among gun users: 64% of trap/skeet/clay shooters, 46% of rifle target shooters, and 37% of pistol target shooters were also hunters. Approximately one in four archers were involved 10 years or more, and 29% of the archers were first-time participants. Twenty-nine percent of archers also hunted with a bow.
TABLE 10. Shooting Sports, Archery, Darts, and Fishing (millions of participants)
BBs and Air Rifles
Considering that competitive air gun shooting is a safe sporting activity, with no reported injuries to any competitor, it is reasonable to conclude that injuries related to BB guns and air guns are secondary to inappropriate and unsafe use of the equipment. If BB guns and air guns (Airsoft guns in the Japanese literature198) are viewed in their proper role as sports equipment, and used safely with appropriate supervision, the injury problem can be virtually eliminated.
Yet, eye injuries related to the shooting of BB guns and air guns have been a source of concern and frustration for ophthalmologists. Despite the recommendations of Canadian ophthalmologists, nonpowdered firearms were excluded from the Canadian Firearms Act 0f 1995 and were not included in 2003.199,200 BB or pellet guns are responsible for 5.13% of all injuries in the USEIR database.201 Although the occurrence of eye injuries from BB guns and air guns (including paintball) has increased between 1984 and 2001 (see Appendix 1), there is no information as to the injury incidence, because the use of BB guns and air guns is not known and the proportion of the injuries related to paintball cannot be separated from the total. What is known is that: approximately 3 million air guns were sold in the United States in 1980; that there are approximately 31,500 BB/pellet-gun–related injuries every year, of which approximately 2000 are hospitalized; and that 80% of the injuries occur in the 5 to 14 year age group.202
Unsupervised access to air guns and unstructured gun use are the principal risk factors for ocular injury. The victims were most likely to have been shot unintentionally shot by a male friend at the friend's home, using the gun for a purpose other than target practice, using it without adult supervision.203,204
Gas-propelled guns have three primary methods of propelling the projectile. (1) A spring-piston air gun, when cocked, draws air into a cylinder and tensions a spring, When the trigger is pulled, the spring pushes the piston forward, compressing the air that fires the projectile at muzzle velocities up to 600 ft/s. (2) Pneumatic air guns compress air that is released when a valve is opened on trigger depression. The multiple pump compression system, introduced in 1972, achieves the highest velocities—more than 900 ft/s. (3) Compressed-CO2 guns have typical muzzle velocities in the 400 to 500 ft/s range.202,205,206 The velocity loss of a BB over a typical 20-foot firing distance is negligible. A BB starting at 260 ft/s loses only about 1 ft/s velocity per foot of distance traveled.207 The original, inefficient “toy” BB guns, with smooth barrels that were larger than the missile have been replaced with air guns with rifled barrels, tight-fitting missiles, and pneumatic chambers that can be pumped to dangerously high levels. Technology has converted a “toy” into a potential weapon with the ability to kill.205
Despite advances in surgical technique,208 the majority of eyes perforated with pellets or BBs suffer permanent visual loss, with many resulting in enucleation.204,209–211 Most (77%) of the patients are in the 7 to 14 year age group, and almost all the others in the slightly older 15 to 24 year age range. Forty percent of injured eyes become legally blind, and 12.5% to 18% are enucleated as a result of the injury, which most commonly occurs at Christmastime to unsupervised children, often from ricochets from improper (hard) target backstops. Complete blindness may occur from sympathetic ophthalmia affecting the uninjured eye.212–214
Injuries secondary to BB guns and air guns were the principal diagnosis in 16.6% (4982 cases) of eye injuries resulting in hospitalization in the United States between 1984 and 1987.215 BBs caused 8 of 48 perforating (through and through) injuries to the globe. The fact that perforating BB injuries have a poor prognosis is because of the tremendous force transmitted to the globe as it creates two blunt openings approximately 5 mm in diameter (Fig. 12).216 BBs were responsible for 16 of 222 ocular injury cases in patients admitted to a children's hospital. Six of the 16 resulted in blindness in the injured eye.217 Twenty-three of 278 childhood traumatic eye injuries admitted to Wills Eye Hospital were the result of BBs.22
BB guns and air guns are not given the respect they deserve as potential weapons with blinding and killing power.210,218,219 In 2001, NEISS estimated that 29,617 injuries from gas, air, and spring-operated guns were seen in U.S. emergency departments, of which 2994 involved the eye. Of the total injuries, approximately two-thirds were to children aged 14 or younger, and approximately one-third of the eye injuries required hospitalization.32 Patients who require hospitalization and surgical intervention from BB eye injuries have a high risk of enucleation.220 Of 32 patients treated with surgical intervention at the Wilmer Eye Institute between 1970 and 1981, 22 had penetrating injuries from the pellets, 19 had their penetrated eyes enucleated, and the remaining three had vision worse than 5/200.221 Of the 80 eyes removed due to sports-related injuries at the Massachusetts Eye and Ear Infirmary between 1960 and 1980, 36 were because of injuries from BB guns.222
A standard BB (0.345 g) will penetrate the globe at speeds higher than 236 ft/s (72.0 m/s) and result in injury at the vitreous base at an average speed of 205 ft/s (62.3 m/s).46 Round, smooth, relatively lightweight BBs are prone to embolize if they enter the vascular system, with potential severe visual and systemic results.202,206,223 Higher powered general-purpose air rifles, advertised in children's magazines, may have muzzle velocities as high as 620 ft/s (189 m/s), which is well above the 408 ft/s (124 m/s) velocity required “for penetration of skin, bone, and moderate tissue, or if no bone is encountered, of skin and deep tissue.”
Because BB guns cannot be made safe and still have any utility (Table 11), the only means of controlling injuries is to keep them out of the hands of unsupervised children and subject them to the same safety precautions and laws as apply to weapons using gunpowder (firearms).201 Air and BB gun sales are closely controlled in New York City,206 but are mentioned in the laws of only 28 states. Some of that legislation explicitly excludes them from consideration as dangerous weapons or firearms.205 National legislation that specifically equates all guns with lethal potential as firearms is an essential first step in the educational process.
*Distance from gun muzzle that BB hits ground when gun is fired parallel to the ground at a height of 5 feet above the ground.
In future attempts to control BB and air gun injuries, several points must be considered. First, with supervision, BB and air-powered weapons can be safe training devices for children who will later move up to the responsible use of gunpowder-propelled firearms. BB injuries, deaths, and blindness will continue as long as children have the feeling they are playing with toys and the true danger of these weapons is not stressed or their use supervised. Because it has been shown that parents who allow their children to have BB or pellet guns appear to misperceive their potential for injury and allow their children to use the guns in an unsafe manner,224 specific educational material should be available to the parent before purchase, and both parent and child should jointly take a gun-use training program before using the gun.225 When parents purchase such a gun, they must recognize it is a firearm, dangerous both to the child using it and to innocent bystanders. The child must never be allowed to use the gun except under direct, personal supervision of the adult.226
Second, the immediate answer does not lie in the development of better surgical techniques. Our record for salvaging these eyes has been, and remains, quite poor.204,209,212,221,227–230 As is the case of most eye injuries, the best way to prevent loss of vision from air guns is to prevent the injury from occurring.203
Third, the BB gun or air gun cannot be made safe. For a BB projectile to be beneath the kinetic energy of 0.03 J that will result in contusion eye injury, the muzzle velocity would have to be reduced to 43 ft/s (13 m/s). When fired in the horizontal direction from a height of 5 feet, the BB would travel a mere 24 feet,45 thus would appeal only to the most placid child. The child and the parent must realize that an air rifle pellet contains more energy than an individual duck/pheasant shotgun hunting shot (Table 12).
Fourth, a major legislative battle to ban BB guns and air guns would probably be ineffective even if won. There would be years of appeal on Constitutional grounds, and the extensive reservoir of several million BB guns and air guns would still be available to youngsters.
Fifth, eye protectors are available that will give essentially total protection, but how do we get persons to wear them? The use of protective goggles, which several manufacturers package with the firearm, would prevent most ricochet injuries (26% of BB eye injuries)204 to the user231 but would not help the person usually injured—the one accidentally or intentionally shot by the person with the gun.
Thus, it seems we are presented with the hard truth. BB guns and air guns are widely distributed throughout the United States; they are dangerous; and they cannot be recalled. In one study, more than 40% of BB and pellet eye injuries occurred when someone actually pointed the air gun at a person and pulled the trigger, showing a lack of respect for the dangers of air guns.203 Therefore, our best means of decreasing eye injuries is by a massive educational campaign aimed at teaching the user to have the same respect for a BB gun or air gun as they do for a firearm. (Children are rarely injured with firearms—everyone knows you can get killed with a shotgun.) To emphasize that BB guns and air guns should be treated as firearms, legislation classifying BB guns and air guns as firearms is recommended.
The National Rifle Association (NRA) has committed its vast educational resources including its 25,000 NRA-certified instructors, to a stronger initiative in the area of air gun safety, particularly as it pertains to eye injury. This includes special air gun safety training programs for use by schools and other community agencies and organizations. The NRA has also revised its training material—used by millions of persons annually—to place a special emphasis on air gun safety, including coordination of safety programs with groups such as the Boy Scouts, the 4-H, and the American Legion.232 There needs to be a more concentrated effort to make available community recreational facilities for persons who wish to shoot air guns in a supervised and safe environment, as well as an emphasis on parental responsibility and supervision of youngsters using air guns.233 The Non-Powdered Gun Products Association (NPGPA), which has published targeting safety rules, should establish a certification council to ensure that BB guns and air guns meet the safety standards specified in the Standard Consumer Specifications for Non-Powder Guns (ASTM standards F589 and F590). Prospective studies are needed to evaluate the effectiveness of educational programs on the incidence of eye injuries.
It is time for a coordinated approach by the public, police, sporting associations, manufacturers and retailers, and politicians.234 The impetus to start an effective process should come from the medical community because this is where both the greatest exposure to the problem and the greatest expertise in solving it are to be found.
The shooting sports include hunting for game and birds with rifles and shotguns, shooting at stationary or moving targets with pistols or rifles (air or gunpowder), and downing clay discs (pigeons) with shotguns.
It is so rare for elite shooters to be cross-dominant that a right-handed shooter with a dominant left eye should be coached from the start of his or her career to shoot left-handed (or vice versa), because the dominant eye is more important than the dominant hand for shooting accuracy.235–237 However, when one shoots right-handed for a lifetime, switching hands may prove inconsistent with good performance—even if the dominant sighting eye is lost in an accident. In these cases, a parallel sighting rib will allow trap shooters to use the nondominant eye while maintaining the preferred shooting shoulder. It is usually stated that pistol shooters need 20/20 near visual acuity for proper sight alignment, while elite rifle shooters usually need 20/20 distance acuity.238,239 However, I have found that most presbyopic shooters prefer to have the target blurred by no more than an add of +0.50 to +0.75 diopter, which makes the combined blur of sight and target approximately the best combination for both pistol and rifle. Shooting glasses frequently are tinted or polarized. Choice of tint varies among shooters, with waterfowl and snowfield hunters often having a preference for glare-reducing polarizing lenses and skeet and trap shooters tending towards brown, bronze, yellow or light gold tints.240
Although most firearms injuries are the result of intentional assault,241,242 and are thus largely unpreventable, there is also a potential for blinding ocular injury from target shooting and hunting accidents. Of the 590 gunshot eye injuries in the USEIR database, 541 (92%) were secondary to violence. The 39 injuries from sport shooting and hunting were serious (72% open-globe, 21% enucleation or no-light-perception) and occurred mostly in males (97%) between the ages of 20 and 50 (79%). None of the injured shooters was wearing protective eyewear. Two of the 7 injured target shooters were struck by fragments of the target (aluminum can) or casing from a misfired bullet; 3 were accidentally shot by another shooter on the range; and 3 were injured by the swinging arms of the clay/skeet throwing apparatus. Twenty hunters were accidentally shot, usually with a shotgun, by another hunter in their party. Two hunters were shot by the landowner for hunting while trespassing. Two elderly men (76 and 85) were injured by the gun on recoil, with 1 suffering dehiscence of a long-incision cataract wound by the telescopic sight that rebounded through his street-wear eyeglasses. Eight of the 32 injured hunters were not injured with a firearm; 3 cut their eye while cleaning a shot deer, 3 were hit by tree branches, and 2 were hit with wire used for towing or fences.
The primary way to avoid shooting eye injuries is by proper gun handling and shooting technique. In 1994, 32% of American households owned a shotgun or rifle, 25% owned a pistol, and 59% owned no guns.243 Because only 56% of gun owners have received formal training and 21% of gun owners keep a firearm both loaded and unlocked in the home, appropriate gun storage and training would help to reduce firearm injuries.244 In 1995, 17 million persons purchased hunting licenses in the United States. New York State requires that all first-time hunting license holders complete a hunter education course. Of 125 incidents in which the injured hunter is mistaken for game (the primary contributing factor for gunshot injuries to hunters), 117 hunters (94%) were not wearing hunter orange.245,246 The time to start training for safe gun handling is in youth. A number of training programs, such as the Home Firearms Responsibility courses given by the NRA and safety pamphlets are available, but the best education is a good example set by responsible adults.
There is no currently available protective eyewear that can withstand the impact of a high-powered rifle bullet from long distances or shotgun pellets from within 15 yards. Yet, serious,247–249 sometimes bilateral,250,251 eye injuries frequently occur with shots from longer distances, gunpowder blasts,252 blank cartridges,253 ricochets, and impacts with other objects (tree limbs, knives, wire)201 that can be prevented with appropriate eyewear. Eyewear with polycarbonate lenses, integral side shields, and a retention strap is extremely effective in protecting the eyes from shotgun pellets in the very hazardous 15 to 40 yard range.254,255 Eyewear that passes both ANSI Z87+ and the much more stringent military ballistic test for eye armor256 is readily available and inexpensive.
Archery target shooting (longbow, recurve, compound or cross bows, with or without sighting aids) has a minimal eye injury risk. The USEIR database includes three archery-related eye injuries. A 6-year-old girl had an open-globe injury when shot with an arrow. Two male archers had contusion injuries (retinal detachment, retinal hemorhage), one, wearing street-wear glasses, was struck with the bow while shooting an arrow, the other was struck in the eye with the sighting tube that dislodged while shooting. Playing with bow and arrow is a significant cause of eye injuries in India.29,257,258 and Norway.259 Adult260 and toy261 bows and arrows have sufficient energy to penetrate through the orbit into the brain.
Suggested protection is eyewear with shatter resistant lenses for those archers who wear prescription eyewear. The functionally one-eyed should wear eyewear that passes ANSI Z87+ or ASTM F803. There are ASTM standards to assure that bows (F1832, F1880, F1544 F1363), scopes (F1753), cords (F1752, F1648, F1436), and arrows (F1889, F1435, F1352, F2031) are properly constructed. Bows and arrows should not be given to children for use as toys.
Although military injuries are not truly sports-related injuries, the same principles of prevention apply. Witnessing the results of monocular or bilateral blindness suffered by young men during the Vietnam War and realizing that a substantial percentage of war-related blindness is preventable provided my personal impetus for involvement in the prevention of traumatic eye injuries. The incidence of eye injuries increased with the development of war munitions—land mines, artillery shells, and bombs—that accurately disperse high-velocity shrapnel fragments among the targeted personnel. Between 6% and 9% of all Vietnam War injuries involved the eye, resulting in permanent visual impairment and blindness in thousands of American soldiers.262,263 Of all hospitalized casualties of the Yom Kippur War of 1973, 6.7% sustained ocular injuries, of which 24.4% were bilateral.264 Ophthalmic injuries, usually caused by munitions blast fragments,265 accounted for 13% (19/149) of all ground war casualties from October 17, 1990, to April 13, 1991 in Operations Desert Shield and Desert Storm. Although most troops were issued protective goggles, only 3 of the 92 U.S. soldiers with eye injuries were wearing them at the time of their injury.266 None of the military who suffered eye injuries (6.8% of all casualties) in the Lebanon War were wearing eye protection.267
Between 1980 and 1993 there were more than 27,000 deaths among the U.S. military personnel who served 28 million person-hours on active duty, averaging approximately 5 deaths per day. Hostile action or war accounted for only 2% of the total while 60% died from largely preventable unintentional injuries that occurred during their day-to-day activities and off duty.268 Most military eye injuries also were not combat related, but occurred from motor vehicle accidents, fighting, and occupational or sports activities. One in 58 eye injuries required treatment in a hospital.269
Laser weapons, small enough to be attached to an M–16 assault rifle, yet effective at a distance of more than 1 km, can produce blindness with a microsecond pulse of light from retinal burns and subretinal hemorrhage.270 Laser eye protection can impact performance and color identification in protected military personnel.271 Because huge numbers of civilians and military personnel will not have appropriate laser protection and may be exposed to blinding lasers mounted on rotary turrets attached to tanks or other military vehicles, there has been a plea from concerned physicians to ban the antipersonnel laser.272,273
The need for a comprehensive eye protection program in the military cannot be overemphasized.274 If eye armor had been worn by troops in the Vietnam War, it is estimated that 39% of the eye injuries collected by the Wound Data and Munitions Effectiveness Team would have been prevented.275 The military has a combat eye armor program underway that is well accepted and has prevented eye injuries.276,277 Because soldiers have occupational exposure to eye hazards that are comparable to those in civilian industry,278 the military should enforce interventions to prevent work-related eye injuries that have been effective in preventing civilian occupational eye injuries.279,280 Protective sports eyewear should be issued to military personnel at risk for sports eye injuries.
Although fencing is a relatively safe sport, two fatal injuries (penetration of a face mask by a broken foil with intracranial entry through the orbit and penetration of the neck over protective bib) and a serious hand laceration with the side of the blade have prompted the formation of an ASTM committee on fencing safety, which wrote performance standards for fencing surfaces (F1543) and the impact attenuation properties of body padding and protective wear (F1631). Because the mask that permitted fatal penetration tested as “good,” there is at least one known death that might have been prevented by stricter mask penetration requirements (Fig. 13). There is a significant discrepancy between the “punch test,” mandated by the International Federation for Fencing (FIE), which requires that a mask resist perforation by a conical punch (69N) and the force of a broken épée blade for an extension lunge from a stationary position on a hard stationary object (4,000N).
The breakage characteristics of foils are an important consideration. Better foils break with a relatively square end, although they almost always have one or two sharp, short protrusions and a small cross-sectional area at the break point (2.5 × 4 mm for foil, 1.5 × 5 mm for saber, and 4 × 4 × 5 mm [triangular] for épée).281 The rate of breakage is high. (A competitive fencer usually breaks six or seven blades per season and takes four to five weapons to a match.) Some experts believe that metal blades will someday be replaced with fiberglass or carbon-fiber blades, which would be lighter, have fewer breaks, and have less lethal-shaped break surfaces; others believe that metal blades can be improved with newer metallurgical techniques.
A lawn dart is approximately 12 inches long with a heavy metal or weighted plastic tip on one end and three plastic fins on a rod at the other end. Although the tip may not be sharp enough to be obviously dangerous, these darts, even when thrown underhand, can penetrate the skull and the eye. Lawn dart injuries have a 4% fatality rate and account for an estimated 675 emergency department visits per year; head injuries account for 54%, eye injuries 17%, and face injuries 11%. Hospitalization (54%) is often required for eye and brain injuries The 10 to 15 million sets of lawn darts remaining in the homes of Americans after their sale was banned by the CPSC on December 19, 1988, should be discarded.282
Indoor darts, with an 8-inch maximum length and 18 g maximum weight, rarely result in eye injuries when National Dart Association rules of play are followed. However, children rarely follow the rules and their thrown darts may cause penetrating or perforating eye injuries with poor visual outcomes, from the initial injury, or later irreversible amblyopia or endophthalmitis.283–285 Games involving darts are not appropriate for children unless there is strict adult supervision and the rules of play are followed.
Fishing (53.1 million participants) was second only to bowling (55.5 million participants) as the most popular activity in the SGMA study. Fishing attracts all age groups (32% under age 12 and 12% over age 55), and approximately 20% of those who fish call it their favorite activity. Only 7% of non-fly–freshwater fishers were new to the activity in 2001, while more than half have been involved 10 years or more.
Fishing was responsible for 113 of the 702 (16.1%) total sports eye injuries and 50 of the 177 (28.2%) open-globe injuries resulting from sports in the USEIR database.201 The fact that 44.2% of fishing-related eye injuries were open-globe injuries results from several factors: fishhooks are sharp; sinkers have a concentrated mass that fits within the orbit; the fishing line can act as an elastic cord when the hook suddenly releases from an underwater obstruction, propelling the hook and sinker toward the sighting eye; and pole tips are whipped around in close proximity to other fishermen on shore or a boat. Fishing injuries from hooks,286–288 sinkers,289–293 pole tips,201 and fishing spears or harpoons294,295 are usually serious. Available data do not always separate fishhooks from sinkers or other causes of fishing eye injuries, so it is not yet possible to determine how many fishing injuries, from sinkers or pole tips, really belong in the “somewhat larger” category to follow. Spectacles, with polycarbonate or Trivex lenses, whether in the form of sunglasses (preferably polarized) or corrective lenses, offer protection and should be worn at all times by fishermen.296
As discussed previously, lacerating eye injuries from shattered eyewear are almost totally preventable.
Small, Somwhat Larger, Higher-Velocity Projectiles
The airsoft is a toy gun that shoots 6-mm diameter plastic bullets (0.12, 0.2, and 0.25 g) at 61.5 to 74.9 m/s. The projectiles have caused hyphema, vitreous hemorrhage, and cataract. The airsoft has blinding potential and should not be sold as a toy.198,297,298
Paintball (often called war games, survival games, Pursuit, or Gotcha) started in New Hampshire in 1981 when 12 friends used air guns that fired capsules filled with paint and designed by foresters to mark trees for harvest in a “survival game” in which the participants were able to eliminate opponents from the game by shooting them with paint pellets. Paintball, now played in more than 40 countries, continues to grow in popularity, with an increase in the United States from 5.9 million participants in 1998 to 7.7 million participants in 2001. The average player is a man (81%) 20.7 years old, who has played for 3 years. Frequent players (more than 15 days per year) number 1.4 million.35
Paintball violates the basic teachings of traditional firearms safety courses, which emphasize two absolute rules: always positively identify the target and never point a firearm (including an air gun) in the direction of any person, animal, or object other than the intended target.233 The intentional firing of a missile at another individual in peacetime, as a game, has been criticized by the Boy Scouts, the NRA, and the Shooting, Hunting and Outdoor Trade (SHOT) industry, who strongly emphasize the safe use of firearms and strict adherence to firearm safety rules. Yet, the appeal of war games has lured players and started a cottage industry of air gun and paint capsule manufacturers as well as field operators. Early on, the rapidly growing sport had no controls as exemplified by the lack of age restrictions on the sale of paintball guns.
It soon became apparent that the paint capsules were responsible for severe (7.8% open-globe) eye injuries. Players and field operators then began to use or distribute industrial safety, motorcycle, or ski goggles, despite the fact that these goggles were never tested for paintball and that industrial goggles have the warning that they are not designed for sports use.299 This eyewear often failed, resulting in severe injury to players who had assumed they were protected (Table 13).
TABLE 13. Paintball eye injuries related to protective
As the sport grew in popularity, there was a slow shift in philosophy away from the original “hunt and be hunted.”300 In a concerted effort to make the sport safer, the paintball industry asked the ASTM eye safety committee for assistance, and an ASTM task force on eye protectors for paintball was formed in May 1994. Paintball now has its own ASTM subcommittee and there are now standard specifications for paintball eye protective devices (ASTM F1776; Fig. 14), field operation (ASTM F1777), marker warnings (ASTM F2041), and paintballs (ASTM F1999). Tree-marking capsules, with indelible paint, have been replaced by water-soluble paintballs. The paintball “gun” is now a paintball “marker,” and a player who is eliminated from competition is “marked” rather than “killed.” Organized paintball is now a variant of “capture the flag” in which there are team objectives, and opponents are eliminated by being “marked.” Automatic markers, in which more than one paintball is discharged for one depression and release of the trigger, have almost totally been eliminated, but the complete elimination awaits finalization of a marker standard. Red paintballs (which may be confused with blood) are prohibited from many fields.
At this time, the paintball mark is a nontoxic, water-soluble dye, contained in a spherical, usually gelatin capsule—the paintball (3.3 g, 17 mm diameter)—that is designed to break on impact. The paintball is propelled by an air gun, called a paintball marker, at a velocity not to exceed 91.4 m/s (300 ft/s, 204.5 mph). Although participants normally wear protective clothing and safety equipment, if a direct impact of a paintball on the body does occur, it is moderately painful and results in bruising and localized hematoma, 2 to 3 cm in diameter. These welts are usually taken in stride by the player and are regarded as part of the game. However, the impact of a paintball on the unprotected eye is associated with severe injury. Pig eyes rupture when impacted with paintballs fired from closer than 4 meters (Fig. 15).301
As paintball increased in popularity, the problem of associated eye injuries became increasingly obvious. Of 77 paintball-injured eyes reported to the Canadian Ophthalmological Society between 1984 and 1998, 33 (43%) were legally blinded.4 As paintball increased in popularity, eye injuries became apparent. While no eye injuries from paintball were reported to the Eye Injury Registry of Indiana from June 1992 to June 1996, 11 injuries were reported over the next 2 years, representing 4% of all ocular trauma reports.302
The widespread use of protective eyewear has greatly decreased paintball eye injuries,303 but more work needs to be done in this relatively new and rapidly growing sport. The current ASTM F1776 eye protector standard will need some modification to help prevent dislodging of protective devices by tree branches and field equipment. The sport needs a governing body with the authority to control potentially unsafe practices of some marker manufacturers and field operators.
There are 8.6 million (76% male) frequent (more than 25 days per year) golf players among the 29.4 million people who played golf at least once in 2001. Golf players tend to be older (average 38.2 years), participate longer (average 13 years), and be more affluent than the players of most other sports.35
A typical male PGA Tour player produces an initial ball velocity of approximately 160 mph with his driver. In comparison, a typical male recreational golfer may only generate a ball velocity of 130 mph, approximately the same velocity as a PGA Tour player's 5 iron. The extreme elasticity of the golf ball results in a ball velocity up to 1.5 times more than the club head velocity before impact.304 A United States Golf Association (USGA)-approved ball must weigh less than 45.9 g (1.62 ounces) and must be more than 4.27 cm (1.68 inches) in diameter.
Golf is not a common cause of eye injuries, but those that do occur from the ball or club (or rarely the golf tee)305 are usually very serious.306–308 For example, a golf ball moveing at 59 mph can rupture a pig eye.309,310 Of the 28 golf injuries (21 ball, 5 golf club, 1 shattered eyewear [club], 1 uncertain) in the USEIR database, 12 were open-globe.201 Golf accounted for 11 (14%) of 80 sports-related eye injuries that resulted in enucleation at the Massachusetts Eye and Ear Infirmary from 1960 to 1980. Golf balls were responsible for 8 of the 11 lost eyes, and golf clubs for the other 3. The only sports resulting in more enucleations were those involving BBs (45%) and arrows/ darts (15%).222 The reason for the high enucleation rate is that both a golf ball and the head of the golf club are hard, travel at high speed, and can fit within the bony orbit, transmitting all of the energy directly to the globe with resultant rupture or disorganization of the eye. The impact from a golf club between the globe and the temporal orbital rim had sufficient energy to cause optic nerve avulsion in a 10-year-old boy.108
Most persons do not realize that liquid center (liquid contained under pressures as high as 2000 to 2500 pounds per square inchi [psi])311 golf balls may explode130,312–314 and are potentially hazardous if cut open, releasing the liquid with force sufficient to penetrate the eye and orbital structures.311,315,316 Fortunately, major manufacturers use nontoxic liquids (such as corn syrup with added salts)304,317 rather than the sulfuric acid, barium sulfate and zinc sulfide compounds used in the past.311,315,318,319 Because products change without notice and one cannot be sure what is in a liquid center golf ball, it is wise to avoid the temptation to cut open a liquid-center golf ball.
Most golf injuries could be avoided if golfers check to be sure the way is clear and that they yell “Fore” before hitting the ball or swinging the club, with special care to be certain that no curious children are directly behind at the start of the backswing.320 Golfers should wear sunglasses or prescription eyewear with polycarbonate or Trivex lenses.
Racket and Paddle Sports
These sports are enjoyed by approximately 40 million Americans (Table 14). Racquetball has the strongest core (over 25%) of frequent players. The traditional family games—table tennis and badminton—have suffered as family time diminished and children turned to television, computers and video games. Overall the participation in racket and paddle sports has diminished over the past 5 years, however, the percentage of female tennis participants grew from 40% in 1990 to 50% in 2001.35
TABLE 14. Racquet and paddle sports (millions of players)35
*2000 for squash
Racket sports are a common cause of serious eye injuries. In Canada, the 1135 racquet-sport–related injuries (47 blind eyes) accounted for 24.5% of all reported sports-related eye injuries and 8.8% of eyes blinded from sports.321 In the United States, racket sports were responsible for 40.3% of sports-related eye injuries seen in one private practice and 23% of all admissions for hyphema to the Massachusetts Eye and Ear Infirmary.16 Racket sports caused 42% of the injuries and 57% of admissions, including two open-globe (one enucleation) injuries, to the Manchester Royal Eye Hospital from January to July 1987.322 A survey of 797 Midwest ophthalmologists found 848 racket sports eye injuries (tennis, 207; racquetball, 70; badminton, 5; squash, 10; racket sport not specified, 458) that included 16 open-globe injuries and 10 loss of vision or eye.323 The risk of eye injuries for 100,000 playing sessions varies depending on the racket sport: squash, 5.2; badminton, 3.6; tennis, 1.3; table tennis, 0.1.324 Many studies have shown the ocular risk of participating in squash, racquetball, tennis, and badminton.325 There is no correlation of player's level of experience with eye injury.326–328
Initially, most handball, racquetball, and squash eyeguards were wire or injection-molded polycarbonate lensless protectors (Fig. 16) that seemed to offer protection by reducing the size of the orbital entrance.92 Impact testing with rackets showed that these eyeguards were virtually indestructible, yet injuries were occurring to an alarming number of players wearing lensless protectors.
The choice of inappropriate eyewear has resulted in many preventable racket-sport eye injuries. Shattered spectacles caused the most serious of these (open-globe injuries). An open-globe injury from shattered eyewear was especially distressing to a one-eyed attorney, an avid racquetball player, who lacerated his only eye when he was hit with the opponent's racket and his street-wear spectacle lens shattered.329 Glass and allyl resin spectacles have shattered, lacerating globes, spectacle frames have failed, and lensless eyeguards have allowed the ball to deform, passing through the protector into the eye (Fig. 17).326,328,330–332
In 1979 and 1980, the eye safety committees of the CSA and the ASTM began independent but cooperative studies on the mechanism of failure in existing protective devices. The committees determined the speeds of racket and ball and tested various types of eye protectors by mounting them on a headform, impacting the mounted protector with balls and rackets at various speeds, and using high-speed photographs to record the results for analysis. This work resulted in the publication, in 1983, of performance standards for racket sport eye protectors.129,333
Despite the acceptance of ASTM racket sport standards and the existence of certification councils in the United States and Canada, some major manufacturers still promote unsafe eyewear for use in racket sports (see Fig. 9). The wearing of inappropriate eyewear is especially dangerous for two reasons: the player is not given the protection that certified eyewear affords, and the potentially hazardous eyewear may give the wearer a false sense of security about the amount of protection available and may encourage risk taking and/or bad habits on the court.331,334
Table tennis requires no eye protection, and there is not enough data on jai alai to make specific recommendations. All other racket sports players should be wearing eye protectors that conform to ASTM F803 or CSA P400.76 Several squash, handball, and racquetball governing bodies have accepted their responsibility for preventing predictable injuries to their player-members. Tennis and badminton governing bodies should, as a minimum, make players aware of the eye injury hazard in these sports and recommend appropriate eyewear.
Since approximately 1980, when the St. Louis Jewish Community Center required eye protection for all racquetball and squash players, only 2 of the club's 14,000 members have resigned because of this policy, which is strongly enforced. Strong support to eye protection for all racquetball players has come from National Racquetball magazine, which has published numerous informational articles on protective eyewear and taken strong editorial positions on mandatory eye protection for racquetball players since the early 1980s. The American Amateur Racquetball Association (AARA), which took the place of the United States Racquetball Association (USRA) in 1982, has given wholehearted support to preventing racquetball-related eye injuries. In 1982, Michael Arnolt of the AARA found that 61% of the membership and 77% of the former USRA officials thought that eye protection should be mandatory. A variety of racket sport eye protectors are available (see Fig. 10). Their widespread use will reduce eye injuries in these sports.75
The increased use of protective eyewear in racquetball and squash, compared to the lack of protective eyewear use in tennis and badminton caused a dramatic shift in the distribution of racket sport eye injuries in Canada—injuries are increasing in unprotected players and decreasing in protected players (Table 15).
(Data collected by T. Pashby from members of the Canadian Ophthalmological Society)
Handball (the original racquet sport) type games date back to 2000 BC in Egypt and 1500 BC in Central America. The modern game is played by two players (singles) or two pairs (doubles) on a court (20 feet wide, 45 feet long, and 20 feet high) with one, three, or four (the most popular) walls. The 4.8-cm diameter, 65.2 g, moderately lively (bounces 3 ½ to 4 feet when dropped from height of 5 feet 10 inches at 20° rubber ball is struck with either hand (55 to 70 mph),332 with the hand wearing a nonwebbed, snug-fitting, soft glove.
Handball, responsible for approximately 900 eye injuries per year, is of historic significance because the first racket sport eye protectors developed were the lensless rubber-covered wire eyeguards designed in an attempt to reduce eye injuries in this sport. Because presently available lenseless eyewear has not prevented hyphema, commotio retinae, and retinal tears,335 the US Handball Association board of directors voted to require the use of one-piece, lensed, polycarbonate eye protectors by all players participating in nationally administered events in June 1988.336 No eye injuries have been reported in any player wearing the required protector.
Singles or doubles squash games are played in an enclosed court (21 feet wide, 32 feet long, 18 feet high) with 255 g, 27-inch long rackets that have a head 8.4 inches in diameter. The hollow rubber ball (23.3 to 24.6 g; 39.5 to 41.5 mm) is propelled 115 to 140 mph when struck with a racket head speed of 80 to 115 mph. On a backhand follow-through, when the racket is above the shoulder, the racket head velocity drops to 15 to 25 mph.332
The ocular hazards of squash were first documented in the early 1970s. In 56 reported cases, the ball caused approximately three-fourths of the injuries and the racket the remainder. Approximately one-sixth of the injuries were caused by shattered spectacle lenses, which resulted in 6 open-globe injuries. The most common injury was hyphema, with traumatic glaucoma, retinal detachment, and vitreous hemorrhage, and corneal laceration (from shattered eyewear) accounting for the remainder of the significant injuries. The vast majority of injured players were working-age men. Persons with one eye were advised not to play squash and protective spectacles were advised for all players.337,338 Protective eyewear is especially important in players whose eye(s) have been weakened by prior surgery or disease. A 34-year-old man, struck with a squash ball, had limbus to limbus dehiscence of radial keratotomy incisions with expulsion of the lens, total aniridia, and total retinal detachment.339
Serious squash eye injuries reported from several countries in the following years have supported the concept that traumatic eye injuries are not accidents but predictable events,19 almost boring in their regularity and predictability (Table 16). In New Zealand, there was a yearly incidence of 100 squash-related eye injuries, with 50 persons losing useful vision in the injured eye and four eyes lost completely.340 In Germany, 26 retinal detachments caused by squash balls were compared to 500 nontraumatic retinal detachments. The squash ball detachments had significantly worse results 24 months after the injury because of a higher incidence of macular detachment, macular pucker, and proliferation of the retinal pigment epithelium.341
TABLE 16. Squash eye injuries
The risk of one eye injury for each of 5329 squash matches342 shows that the estimated risk that a dedicated squash player has the odds of 1 in 4 for a serious eye injury if he or she plays once or twice a week for 25 years343 (2 matches a week × 50 weeks × 25 years = 2500 lifetime matches) may be conservative and that the risk of serious eye injury to the serious squash player over 25 years may actually approach 50%.
In 1990, the incidence of eye injuries to Australian pennant squash players was found to be 17.5 per 100,000 playing hours, with 26% of players having sustained an eye injury (61% from the racket). Although squash-specific–lensed eye protection has been advocated by ophthalmologists and squash governing bodies, and one-third of the Australian squash players who suffered eye injury were injured more than once, less than 10% used eye protectors in 1990 (mostly after having suffered at least one eye injury from the sport) and 2% still believed that street-wear spectacles offered eye protection.344 As recently as 1995, only 10% of Australian squash players wore protective eyewear, 35% still wore street-wear prescription eyewear, and 15% of players already suffered an eye injury (mostly from the racket).345 The resistance to protective eyewear is evident in an English player who suffered an open-globe injury to an eye already weakened by a prior squash-racket–induced perforating injury that was struck by a squash racket and still does not wear eye protection.21
Eye protection for United States and Canadian squash players has been promoted since 1976, and is now mandated for most players (Table 17). In the future, perhaps eye injuries from squash will be eliminated by the use of certified products by all players. This will not happen until the governing bodies in all countries have the courage to mandate protective eyewear for all. As long as there is peer pressure not to wear protective eyewear, some players will continue to take a needless risk that they do not fully comprehend.
TABLE 17. Organizational Positions on Protective Eyewear for Racket Sports
This relatively new sport (invented in 1949) is played singles or doubles in an enclosed room 20 feet wide, 40 feet long, and 20 feet high. The 5.7-cm diameter, 40-g hollow rubber ball is propelled at 85 to 110 mph by a 56-cm racket with a head diameter of 25 cm and a head velocity of 80 to 95 mph.332
Racquetball is usually played by those in the working ages of 20 to 55. The racquetball professional usually reaches top performance between ages 20 and 30.346 Over a 14-month period from January 1, 1977 to April 1, 1978, six courts at California State University, Long Beach, were used 14 hours per day for a total of approximately 35,280 player-hours. Of 70 injuries that required medical attention, 20 involved the eye, and 3 players required hospitalization for hyphema. The incidence of eye injury was 1 for each 1764 hours of racquetball play with a hospitalization required for eye injury after each 11,760 participation hours.347 Injuries to the face and scalp account for between 50% and 55% of all racquetball injuries, with eye injuries accounting for 5.7% to 12.9%. However, it is likely that the 5.7% figure is too low because globe injuries were triaged from the emergency department directly to the ophthalmology department and therefore not included in the data. Racquetball-related injuries are caused by both the ball and the racket (Table 18), with racket injuries often being self-inflicted.327,348
TABLE 18. Racquetball eye injuries
Two, three, or four players play on a court (20 feet wide, 34 to 40 feet long, and 20 feet high) that has one wall, three walls, or three walls and a ceiling. The approximately 1-pound oval or square wooden paddles are 16 inches (40 cm) long and have a head measuring 8 inches. The hollow rubber ball is 4.8 cm in diameter. The other paddle racket sports are platform tennis, paddle tennis, and Padel, which have somewhat different playing rules, but similar eye hazards.
Pelota Vasca (Basque Ball)
Of the seven forms of pelota vasca, jai alai—played as singles, doubles, or triples—is the most extreme. A 2-foot wicker basket (the cesta) extends the player's throwing and catching hand. The ball approaches the characteristics of a baseball (2 feet [5cm] diameter, 4.5 ounces). The court is a huge three-walled (front, side, back) structure 40 feet high, 40 feet wide, and 176 feet long. There are no data on eye injuries in pelota vasca.
A 2½ foot net, 5 feet off the ground in the center, bisects the 20 by 44 foot court and separates the singles or doubles opponents. The 4.74 to 5.50 g shuttle has 16 feathers fit into a cork base that is 1 inch in diameter. The feathers are approximately 2¾ inch long and spread to 2⅝ (68 mm) at the rear of the shuttle. The 27-inch lightweight (85 to 140 g) racket has an oval head 9 inches wide and 11 inches long. Shuttlecock velocities of experienced players range from 105 to 135 mph.332
Although the shuttle decelerates rapidly, sufficient energy is present, especially after the smash, to cause significant ocular injury. In southeast Asia, badminton is played seriously; in Malasia it accounts for two-thirds of all sports eye injuries and 53% to 56% of hyphemas from all causes.349 Fifty percent of all persons with badminton-related injuries suffer some permanent decrease of best-corrected vision and 11% result in 20/200 or worse, with macular changes, traumatic cataract, and glaucoma the main causes of visual impairment. In doubles, shuttlecocks hit the eye off both the partner's and opponent's racket; but racket impacts, which occur 14% to 48%350 of the time, are only caused by the doubles partner. Because of the potential of injury in doubles from the racket as well as the shuttle fired by friendly forces it is not surprising that 70% of all badminton eye injuries occur in doubles. The racket has enough force to shatter eyeglasses, causing corneoscleral laceration,322,351 but there have been no reports of a spectacle lens shattering on impact from the shuttle.352 Most injuries from the shuttle are to players at the net.322
In Canada, where 2 of the 11 eye injuries reported in the 1976–1977 season resulted in legal blindness,353 the relative incidence of badminton-related eye injuries increased from 1982–1989. In a 3-year period ending June 1989, there were 64 badminton-related eye injuries reported by ophthalmologists in Canada; 57 of the 64 were caused by the shuttlecock.354 Schoolchildren suffer badminton-induced hyphemas while supervised by physical education teachers who rarely recommend protective eyewear.355 Badminton is responsible for 19% of severe sports-related eye injuries in the United Kingdom.20
Sixteen of 231 (7%) competitive badminton players in the 1976–1977 season received an eye injury; three players required hospitalization, and one player required surgery. All of these injuries were from the shuttle, with 81% hit by the opponent and the rest hit by the player's doubles partner or glancing off the player's own racket. 7% of surveyed players reported a badminton-related eye injury.356 No eye injuries have been reported in any player wearing an eye protector.
The 27 by 78 foot (singles) court is divided by a net that is 3 feet high at the center. A felt-covered rubber ball (2 ½ 2 to 2 5/8 inch diameter, 2 ounces) is propelled at 85 to 140 mph by a racket 29 inches long with a head diameter of 12 ½ inches.
Although it is likely that street-wear glasses give some protection from eye injury from a tennis ball,328 sturdy frames that pass ASTM F803 with polycarbonate lenses are preferable to the weaker street-wear frames that can fracture on impact with sufficient force to cause macular injury357 or have lenses weak enough to fracture on racket impact.358 Tennis is the leading cause of eye injuries in west suburban Boston working-aged women359 for three reasons: Massachusetts women enjoy the game, eye protection is rarely worn, and the tennis ball has sufficient energy to detach the retina.360 Injured players tend to return to the game, even after loss of an eye361 or a retinal detachment.362 Even injured players tend not to wear eye protection.361,362
Why do tennis players refuse to wear eye protection? In addition to eye protectors not being fashionable, especially to women, ophthalmologists do not promote, and even discourage, proper protection. Tennis is the most common sport depicted in refractive surgery advertisements as an example of the ability to “play sports without glasses.” A well-known ophthalmologist who had radial keratotomy363 and continues to play tennis without eye protection gave as his reason “It's a risk I choose to take, like sailing or driving a fast car.”364 If a surgeon who knows that his radial keratotomy eye is prone to rupture if struck by a tennis ball chooses not to wear eye protection, how do we convince the general public that eye protection is worthwhile? Protectors will be worn by most tennis players only if the player believes that performance will be enhanced and that the protector is fashionable (with protection as an added benefit). Unfortunately, some glasses and contact lenses that are promoted as performance enhancers, actually may degrade perception of the ball.158,188
Despite a table only 1.525 by 2.74 meters, relative proximity of the players, and high velocity of competi-tive table tennis, there are almost no eye injuries. The 2.5-g, 38-mm diameter celluloid ball, developed in 1900, when driven by a rubber-covered wood paddle, does not have sufficient energy to cause serious eye injury.
Stick and Ball Sports
In some stick and ball sports in which the players are in close proximity, using a stick or crosse to propel the puck or ball, there is eye injury potential from both the ball and the stick. Lacrosse is primarily an aerial game; hockey (ice, field, roller) bandy, and polo are primarily ground games; hurling and shinty have ground and aerial components. There are few injury data for hurling, shinty, and bandy, but the mechanisms of injury and protective suggestions would be similar to the close-proximity ground and aerial sports to be discussed. In other stick and ball sports—baseball, softball, rounders, and cricket—only one player at a time swings a stick or bat, and eye injuries are almost always caused by the ball.
In the Unites States, adult softball has declined in popularity because of a loss of casual pick-up players. Softball is now played by 17.1 million slow-pitch and 4.1 million fast-pitch players; 7.1 million softball players (64% female, average age 20.4) play at least 52 games per year. Of 11.4 million baseball players, 3 million (84% male, average age 17.3) play at least 52 games per year. Lacrosse teams have tripled over the past decade from 661 to 1721, and there are now 1.1 million players of both genders. Ice and field hockey have had a slight decline in participation to 2.3 and 1.2 million participants.35
Intrinsic to hockey are high-mass collisions (checking, sliding into boards and posts); low-mass, high-speed impacts (puck); and slashes (stick). Despite efforts to control fighting365 intentional fist, stick, and illegal body contact are hockey facts of life. Before the widespread use of head and face protectors, 37% to 64% of the total injuries were to the head, with the face receiving the majority of the head injuries.366–372 The probability of a facial injury to the unprotected hockey player is extremely high: 7% in the first year of play, increasing to 66% after eight seasons, and up to 95% for professional players. The average professional player has had, from playing hockey, 1 facial bone fracture, 2 lost teeth, and 15 facial lacerations that required sutures.373,374 Among the most significant ice hockey related injuries were those to the eye.375
Documentation of blinding hockey eye injuries started when Pashby and colleagues376 and the Canadian Ophthalmological Society reported 287 eye injuries (20 eyes legally blinded) in the 1972–1973 season and 253 eye injuries (35 eyes legally blinded) in the 1974–1975 Canadian amateur hockey season (Appendix 2). Castaldi377 pushed for mandatory face protection when two Hartford students each lost an eye in the same season. Horns378 reported 47 ice-hockey–related eye injuries, of which 7 resulted in legally blind eyes, including 3 ruptured globes. Thirty-eight hockey-related eye injuries seen in a Massachusetts suburban practice included an enucleation and legal blindness from a macular scar.379 Prospective studies in Massachusetts during the 1974–1975 season showed that 105 of 124 schools with hockey teams had players that suffered 209 facial injuries with 5 eye injuries and 110 injuries involving the eye area; the only players injured while wearing facial protection were four goalies, who were wearing molded face masks.380 In Montreal, 33 (13.2%) of 250 retinal detachments secondary to contusion of the globe involved ice hockey. The mean interval between injury and preoperative examination was 3 years. Despite surgery, 42.4% of these eyes became legally blind.381 Injuries to the musculoskeletal system are most frequently caused by collisions with players, goal posts and the boards; however, approximately two-thirds of hockey-related eye injuries are because of the stick and the rest are because of the puck. Only a few percent were from collisions, fighting, and other causes.376,378,379,382 Rules changes to keep the stick low and decrease violence certainly help,383,384 but the majority of eye and face injuries would remain despite the rules changes. Because most injuries are accidental, the only means of prevention is protective equipment.
In the 1975–1976 season, hockey face protectors were voluntary in Massachusetts. All of the 70 facial injuries in the continued prospective study involved unmasked players, except 2 to goalies wearing form-fitting face masks and a small chin laceration from an improperly fitted wire-cage face mask that rotated on impact. As face protectors became more widely used (Table 19), the injuries to the eye and face dramatically decreased, so that the only significant injuries seen were to unprotected players (unorganized outdoor games, older players, professionals, and those playing for paid gate) and goalies wearing molded face masks. There have been no instances of injury caused by the face mask either to the wearer or to another player who was not wearing a protector.385–394
To reduce these preventable injuries further, it will be necessary to induce the older players to wear face protectors.395 A major step in encouraging older players to wear protection is the rule in Canada that, starting with the 1993–1994 hockey season, only players wearing full-face protection, or a half shield (visor) plus either an internal or external mouthguard, are allowed to submit a medical or a dental claim for facial injury.4
The full-face hockey protector (Fig. 18), one of the most efficient sports protective devices, was designed as part of a total head protection system in which forces are transmitted to a helmet designed to protect the brain. The current ASTM and CSA standards prevent penetration by the 2 × 0.25-inch hockey stick blade, which was a problem with some early wire face masks.396,397
The hockey visor (Fig. 19) is not recommended because the visor does not prevent maxillofacial and dental injuries (38% of the total cost of all ice hockey injuries),115,398–400 and allows penetration and eye contact by a stick or puck from below (9 blind eyes with visors, 0 blind eyes with full face shields; Appendix 2).
Despite the fact that goalies are far outnumbered by forwards and defensemen, nearly all eye and head injuries to protected hockey players involve goalies who are wearing form-fitting masks.390 The form-fitting goalie face mask is no longer acceptable because: (1) there is little or no protection to the temples and occipital areas of the goalie's skull; (2) players (and the parents of school-age players) often enlarge the eye openings for a larger visual field, thus decreasing eye protection; (3) the form-fitting masks neither spread forces over a wide area nor substantially lengthen the duration over which a force is allowed to act because they bottom out in critical regions401,402 and transmit the forces to the skull, brain, face, and eye; (4) breathing, heat dissipation, and conversation are markedly compromised; and (5) a great range of products exists, from those that are well made with better padding to cheaply mass-produced or incompletely fabricated ones with little or no padding (Fig. 20). The average player usually owns an inferior mask, yet is subjected to slap shots driving the puck at 100 to 105 mph.403
Better protection for goalies lies in a sturdy wire-mask-helmet combination that conforms to the standard specifications of ASTM F1587 (see Fig. 20).404,405 With this combination, the head is better protected against blows from the rear and side; the brain is better protected against concussion as energy is dissipated through the helmet and thicker padding; and the wire mesh allows for better vision, improved communication, and better protection at less cost. Form-fitting goalie face masks are no longer permitted by HECC.
Hockey full-face protectors are now worn by more than 1.2 million North American ice hockey players. These players suffer 70,000 fewer eye and face injuries than they would have were they not protected, with a savings to society of over $10 million in medical bills each year.3 The 1988 Government of Quebec regulation imposing the use of a full-face protector on the 100,000 adult recreational ice hockey players of the province resulted in a net saving of $1.9 million in health care costs between 1988 and 1993.406 Ice hockey injuries occurring above the shoulder have decreased by over 50% since 1976 after face mask and helmet use became widespread.397 Economic studies have shown that if every hockey player were given a hockey face protector for free, society would still make a profit in medical expenses avoided by use of the protective device.407
Eye and face injuries accounted for two-thirds of all injuries in ice hockey before the introduction of mandatory eye and face protection in play sponsored by schools, colleges, and amateur hockey associations. The widespread use of these protective devices has virtually eliminated serious eye and face injuries to protected players.408,409 The existing facial lacerations that are secondary to rotation of loose-fitting helmets could be diminished by converting the single-strap helmet fixation to a more secure helmet fixation system.410 It seems that this obvious problem, with its relatively easy solution, should have been soluble in less than 10 years.411
Yet, constant vigilance is needed.412 Injuries to the cervical spinal column appear to be increasing in ice hockey players.413–419 Some blame cervical injuries, increased player violence, loss of individual freedom, and injurious behavior on the protective helmet/face mask and believe that cervical injuries can be reduced by educational initiatives,420,421 changing from full-face shields to less effective visors,422 or even a return to risk-taking no mask-no helmet play.423 Others believe that removing helmets and/or face shields is not an option because: (1) facial and blinding eye injuries will return and it is neither acceptable nor ethical424 to trade one catastrophic injury for another, (2) prospective studies have shown that the use of full-face shields is associated with significantly reduced risk of sustaining facial and dental injuries without an increase in the risk of neck injuries, concussions, or other injuries,115 and that concussion severity is reduced by the full-face shield,425 (3) the most violent form of hockey (professional) is played without full-face shields, and (4) aggression and violence in ice hockey is a complex psychosocial problem that requires changes in behavior, coaching, and rules.426 Violence and aggression are more predominant in men's ice hockey (in which many players do not wear full-face shields) than in women's ice hockey (in which all players wear full-face shields.427
The National Hockey League, with its apparent acceptance of violence and fighting as a part of the game is a poor role model for youth hockey.428 The attitudes of the coach, players, and referees to the style of play cannot be overemphasized as a factor in injury reduction. The solution to youth ice hockey injuries is rooted in the aggressive safety stand taken by USA Hockey, the national governing body for U.S. ice hockey, which has instituted approximately 40 safety rules since 1983, stresses coach training on safety, and has appointed a risk manager to each of its 11 districts. The Massachusetts Medical Society and Massachusetts Hockey have combined to form the Heads Up, Don't Duck program to decrease the risk of spinal cord and eye injuries. Think First Canada has produced an excellent video emphasizing more safety and more fun by playing “smart hockey.” Eye and facial injuries to spectators429 have resulted in taller protective barriers or nets in some arenas.
Street, Floor, Rink, and In-line Roller Hockey
Testing of the actual energy levels in these sports has not been done, but total eye and face protection would be achieved with an ice hockey full-face mask mounted on a helmet. This combination should be required for all participants.
Street and floor hockey are played outdoors or in the school gymnasium using either regulation or lighter weight hockey sticks and a plastic puck or a tennis ball. Face and head protection are rarely worn, even by the goalie. In 1.5 school years 10 of the 400 players sustained an eye injury.430 One player, who was wearing a helmet, but no face mask, lost an eye when struck with the blade of a plastic hockey stick.431
Rink hockey is played with rink (quad) skates and a lightweight (155 g, 7- to 8-cm diameter) ball. Face protection is mandated for the goalie, but not for the other players.
In-line roller hockey is similar to ice hockey and is usually played in a rink with a hard rubber puck that has ball-bearings or bumps to limit surface friction. Helmets with face masks are mandatory. Testing of the actual energy levels in these sports has not been done, but total eye and face protection would be achieved with an ice hockey full-face mask mounted on a helmet. This combination should be required gear for all participants.
Injuries to the head and face are common in field hockey. The field hockey ball (diameter 7.13 to 7.5 cm; 156 to 163 g), which is extremely hard and can be driven at a velocity in excess of 50 mph by high school girls, has caused an almost fatal epidural hemorrhage from a fractured skull to a Massachusetts high-school player. Of the 14 serious injuries to women playing field hockey at California State University in Long Beach from 1976 to 1979, 4 involved the head and face (3 cerebral concussions and 1 severe cheek contusion with neuropathy of the seventh nerve that lasted several months).432 Tooth injuries in field hockey have increased, prompting the Big Ten athletic rules committee to mandate mouthguards for female collegiate athletes in 1982.433 A 1996 survey of Delaware, Massachusetts, Missouri, New Hampshire, Ohio, and Rhode Island reported 160 occurrences of head injuries to 5070 players. Fifteen of these injuries involved the eye, 10 the eyelids, and 19 the eyebrow. Field hockey eye injuries tend to be severe and include ruptured globes from impact with the stick.20,434 The risk of an eye injury over an 8-year career is approximately 4% (see Table 3). Head, face, eye, and tooth injuries could be eliminated with helmets and faceguards, which are mandatory for goalies but forbidden to other U.S. players. Eye injuries can be reduced or eliminated with eyewear conforming to ASTM F803 for field hockey. Thus far, field hockey officials have no adequate explanation as to why the ball must be so hard, why helmets and face guards are not permitted to players other than the goalie, and why eye protection—at the least—is not mandated.
Polo, a team sport with four riders per side, is often described as field hockey on horseback. An adult male polo player can drive the (7.6 to 8.9 cm, 99 to 128 g) plastic ball in excess of 100 mph. Players wear helmets, but the use of eye and face protectors is spotty, ranging from wire faceguards borrowed from hockey to a double wire bar that will permit penetration by the ball and the mallet (Fig. 21), to no protection at all. There is the risk of being struck in the eye with the ball or a mallet, but no standards exist for eye and face protectors.
Standards and the universal use of adequate polo face masks will come too late for the one-eyed polo player who lost his only eye when struck by a mallet that penetrated a face mask which offered inadequate protection.435
Both men's and women's lacrosse are played with a solid, hard rubber ball (142 to 149 g, 7 cm diameter) that is thrown and caught with an approximately 10 × 12 inch netted pocket on the end of a stick (the crosse) that varies in length from 36 to 44 inches for women and 40 to 72 inches for men. Despite the fact that men propel the ball faster and that men's lacrosse permits body contact, which is prohibited in women's lacrosse, eye injuries occur about 15 times more frequently in the women's game (8-year eye injury risk 6.69% for women and 0.45% for men) (see Table 3).
Men's lacrosse is played on a 60 × 110 yard, marked field. A player may “take out” an opponent who either has the ball or is within 2.7 m of a loose ball by making contact (usually with the shoulder) between the opponent's neck and knees but not from behind. Although the rules forbid taking uncontrolled swings with the stick, infractions occur. All players are required to wear helmets with face masks and attached chin straps (Fig. 22). Before 1978, some masks would admit the lacrosse ball at speeds approaching 90 mph with resultant face and eye injury. Rules now require a vertical bar that prevents ball penetration.436 The face mask offers good eye and nose protection; eye injuries and nasal fractures are rare in protected players.437
The rules in women's lacrosse do not permit deliberate physical contact but the stick can be checked. The wooden stick must have a head less than 9 inches wide. Only the goalie is permitted the use of a helmet and face protector. Should women who play lacrosse wear helmets and face protectors to prevent head, face, teeth, and eye injuries? Several women's lacrosse officials and the leadership of (the now non-existent) United States Women's Lacrosse Association (USWLA), while permitting mouthguards and the voluntary use of eyeguards, are opposed to the concept of helmets and faceguards.438,439 Others believe they should be worn for the good of the players and the sport.440,441
The Women's division of U.S. Lacrosse, which has replaced the USWLA as the governing body for women's lacrosse in the United States, has mandated eye protection that conforms to ASTM F803 starting with the 2005 season.
There is no question that unprotected women's lacrosse players suffer eye and face injuries. Fractured orbits, hyphema, angle recession with lifelong tendency to glaucoma, and ocular contusion have resulted when lacrosse balls or crosses struck unprotected women players.442,443 Among collegiate and postcollegiate women's lacrosse players, 12.6% reported eye injuries, and 4.8% reported residual problems from an eye injury sustained while playing lacrosse.444 Data collected by the USWLA Sports Medical Committee from 1980 through 1983 revealed between 6.2% and 9.9% annual incidence of face, eye, and tooth injuries to players. Most of the injuries were accidental, with approximately two-thirds caused by the stick and one-fifth caused by the ball. Australian data, collected prospctively in 1991 and 1992, recorded head or face contact in 22% of the women's lacrosse players at least once per game.441 During the 1991 season, unprotected Australian women's lacrosse players suffered 13 concussions, 3 broken noses, 28 black eyes, 98 facial bruises, 32 cuts to the face and head, 1 facial fracture, 4 significant eye injuries, and 4 broken teeth while no significant injuries were reported in the protected players. Helmeted players reported 62 examples of significant head and face contact in which they believed the protection prevented injury.445 Based on these findings, three of the four states playing women's lacrosse in Australia allowed the optional use of helmets in their competition starting in 1993.
Women's lacrosse is currently stalled at the same crossroad that confronted ice hockey in the mid 1970s: injuries to the eye and face are common but are denied or trivialized by many of the officials and those who make the rules. The situation in ice hockey has changed: acceptance of total head and face protection has eliminated two thirds of all the ice hockey injuries that occurred without the protectors. Head, face, and eye injuries could be effectively eliminated in women's lacrosse with appropriately designed protectors. Although there have been no significant eye, face, or head injuries to protected players, or any instances of an injury caused by a helmet or face protector when protected and unprotected players played against each other,445,446 and women's lacrosse officials realize that they do not have the right to discourage the development of protective equipment as long as it neither threatens others players nor gives the wearer of such equipment an unfair advantage,447 the International Federation of Women's Lacrosse Associations (IFWLA) rules still state: “Close fitting gloves, noseguards, eyeguards, and mouthguards may be worn. Field players are not permitted to wear protective headgear or face masks.”
The argument against helmets with face masks—that helmeted players will use the helmet as a weapon against unhelmeted players—is ludicrous. If a person has a long stick in her hand and also has a face mask on her face, it is simply more efficient to hit the opponent with the stick. In all instances in which helmets and face masks were optional (Australia, 1993 to present; Massachusetts, 1984 season), there was no instance of an injury caused to an unprotected player by the protective helmet and/or face mask of a protected player, while ball and stick injuries to the unprotected were commonplace.
Although the mandate (effective in 2005) for the use protective eyewear that conforms to ASTM F803 for women's lacrosse (Fig. 23), will reduce eye injuries,443,448 women's lacrosse officials should permit women to wear the same protective head and face gear—so effective in men's lacrosse—to reduce other injuries to the head and face. In addition to protective equipment, rule enforcement and zero tolerance for rules infraction are necessary components of an injury reduction program.449
Box lacrosse is played in an enclosed area, such as a hockey rink, with shorter sticks and a lighter, spongier ball than field lacrosse. Although the rules prohibit wild swinging, hitting from behind, and checking at the head, face, and neck, the games can be quite physical. Head and face protection that meets CSA box lacrosse standards450 prevents most eye and facial injury in box lacrosse.
Although the incidence of eye injury is greater in other organized sports (see Table 3) eye injuries from baseball, because of their occurrence (see Appendix 1)28,451–453 and severity454–456 are a concern. In 1995, an estimated 162,000 baseball injuries in the 5- to 14-year age range presented to emergency rooms in the United States, with ball impact responsible for 55% of the injuries.457 Baseball is a leading cause of U.S. sport-related eye injury.458 In Massachusetts, 1 of every 238 children 5 to 19 years old was treated at a hospital for a baseball-related injury annually.459 Of 5 million Little League players, 1.96% sustained injury of sufficient severity to require medical attention. The head suffered 38% of all injuries, and injuries to the batter accounted for 22% of the total. The pitched ball caused 22% of all injuries, but on the basis that one of five pitched balls became batted balls, the incidence of injury from the batted ball was 361% higher than that from the pitched ball.460 Several major league players have had severe eye injuries from thrown or batted balls. A 1-year prospective study of all eye injuries among approximately 800 Major League players from 26 teams showed that the 24 injuries were distributed relatively evenly among batters, fielders, and those on the sidelines. No permanent loss of vision occurred, but 30% of those injured missed subsequent games because of their eye injury.461
Prevention of youth-baseball–related injuries is multifaceted and includes: (1) eliminating steel spikes; (2) eliminating sliding, or using the breakaway base; (3) eliminating or moving the on-deck circle; (4) screening the dugouts; (5) using protective equipment including batting helmets, catcher's helmets, face protectors for batters, base runners, and catchers; (6) prohibiting intentional body contact between a base runner and infielder making a play at a base; (7) using softer baseballs; (8) restriction on the amount of pitching; (9) motivating players to use proper equipment; and (10) continued surveillance of baseball injuries.457,462–464
The 5-ounce baseball, thrown at speeds up to 100 mph and batted ball even faster, contains an enormous amount of energy.465 Baseball batters struck in the head by fast pitches may suffer concussion, skull fracture, or death, which may be prevented by a helmet that conforms to standards of NOCSAE.132 Ball impacts are common in youth baseball. In 176 baseball games, there were 405 actual player-ball impacts, of which 29 resulted in “major” or “extreme” discomfort to the player. Eighty percent of the impacts were from the pitched ball. Impacts were most common in the 9 to 10 age group, and the injury severity/discomfort was directly correlated with the hardness of the ball.466
The safety of a baseball or softball, as far as brain and cardiac injury are concerned, is related to the hardness of the ball.467 Major League baseballs, wound with wool (Fig. 24), are safer than many Little League baseballs, which are filled with synthetic yarns or hard molded plastics.468 The Reduced Injury Factor (RIF) baseballs and softballs would reduce death from ball impact to the head and chest (there were 68 ball-impact deaths ages 5 to 14, in 1973–1995: 38 from impacts to the chest, 21 from ball impacts to the head, and 9 from ball impacts to other areas)457 but would probably not reduce eye injuries to any significant degree. Because the RIF balls weigh the same (5 ounces) and feel and handle remarkably like a Major League baseball with greatly increased safety, it seems reasonable that RIF balls should be used by all Little League players.66
Ball and bat liveliness (elastic properties) also relate to injury. A livelier bat transmits more energy and velocity to the ball. A livelier ball travels faster when hit and thus contains more energy and gives the fielder less time to react than does a less lively ball traveling at slower speed. Ball liveliness does not correlate with hardness and must be measured separately. Liveliness is measured by the coefficient of restitution (COR), which is the ratio of the velocity of the ball rebounding from the surface of a hard immovable object (e.g., thick steel plate or ash boards backed with concrete) to the incident velocity. A baseball traveling at 85 ft/s (58 mph) rebounding with a velocity of 48 ft/s (33 mph) has a COR of 0.56 and loses 68% of its energy to friction465 compared to the extremely lively golf ball with a COR of 0.8 that loses much less energy to internal friction. Because the hardness and liveliness of the ball relate to injuries, and because brain injury potential can be measured on test head forms with the severity index (SI),469 standards could be set for age groups or divisions that specify the liveliness, hardness, and the maximum allowable SI consistent with the performance demands and skill levels of a particular age group or division.470
Face protectors that meet ASTM standard F910, attached to NOCSAE approved helmets are strongly recommended for Little League batters and base runners (Fig. 25). Face guards reduce oculo-facial injury in receptive youth players and should be required for youth batters and base runners.471,472
Some protectors that pass ASTM F803 for baseball fielders (Fig. 26) have not gained player acceptance. Manufacturers continue trying to develop cosmetically and functionally acceptable eye protection for baseball fielders. Players and parents must be aware that some products advertised for youth baseball batters and fielders (Fig. 27) may only give a false sense of security and no significant protection. The buyer should be certain that the protector was tested to ASTM standards.
Professional players should be aware of the protection offered by the protectors and make their own decision as to whether to use them. The most effective approach to introducing face protectors to baseball would be along the lines that were successful with the hockey face mask—a somewhat gradual approach to younger players, continued gathering of data, then wider use of the protectors as data proved their worth. The evidence has resulted in mandatory face masks for youth batters in Baltimore, Dover (New Hampshire), the South Side Little League and the Dixie Little League.
Players never should wear glasses that have little resistance to shattering when impacted with a baseball (see Fig. 4).358 At least two major league baseball players were seriously injured (Mookie Wilson, lid lacerations, hyphema; Jackie Gutierrez, corneal lacerations) when their flip-down sunglasses shattered on impact with the ball. In 1986 the manufacturer, Vision Master, Inc, Cleveland, Ohio, switched to polycarbonate lenses and there have been no subsequent reported instances of lenses shattering.
Most baseball-related eye injuries could be prevented with real cost savings to society. Because approximately one-third of the total eye injuries occur to batters, faceguards worn by batters (which would also protect base runners) would substantially reduce but not eliminate eye, face, and tooth injuries. The best protection for fielders is to wear eye protectors that pass ASTM standard F803 for baseball.473 The acceptance of softer baseballs, and face and eye protection is hindered by “tradition-bound resistance” on the part of sports officials and some players.474
Women's softball has approximately twice the incidence of eye injuries as men's baseball (see Table 3). Recreational softball has an unknown incidence, but a high occurrence of injuries, including eye injuries. Shattered sunglasses have lacerated globes. Maskless catchers and behind-the-plate umpires, batters, and fielders have all been injured. It is estimated that recreational softball players sustain more than 1.7 million sliding injuries every year—360,000 of them serious enough to require hospital emergency department treatment. Softball injuries cost the public $2.1 billion annually. The widespread use of breakaway bases would eliminate a great number of these injuries and the costs associated with them.475 Bat and ball liveliness should be specified for the field conditions and player skill levels.476
Cricket places extreme demands on the visuo-perceptual system of the batsman. The cricket ball, with an elevated seam, is thrown at approximately the same speed as a baseball but may be bounced with spin that causes the ball to change direction as it hits the ground in front of the batsman.477 Indoor cricket most commonly causes injury to the fingers and the eyes.478 Ruptured globe, retinal detachment, hyphema, choroidal tears with permanent loss of vision, and lid laceration have been caused by the 5.5-ounce hard ball.479,480
In New Zealand, approximately 30% of all sports injuries to the eye are the result of indoor cricket.480 In Australia, cricket contributed to 14.6% of orbito-zygomatic fractures with the ball being the agent of injury in all but one of the patients.481 At least three cricket players with eye injuries were functionally one-eyed prior to the injury.482 The incidence of these injuries could be reduced by wearing eye and/or facial protection as suggested for baseball.
Of the large-ball sports, soccer and basketball are extremely popular; very little equipment is needed and variations of the games may be played by any reasonable number of players. Basketball is increasing in popularity: 38.7 million people participated in 2001 (67% male: 8.7 million played more than 52 times per year). In the Unites States, soccer has fewer participants than basketball, at 19.0 million (55% male, 4.3 million played more than 52 times per year). However, soccer is by far the most popular sport worldwide. In 2001, 24.1 million people played volleyball (38% male, 4.6 million played more than 25 times per year). Touch football (16.7 million participants), and tackle football (5.4 million participants; 2.2 playing more than 52 times per year) are mostly (94%) played by men. Only 0.6 million people participate in rugby in the United States.35
Contrary to previous ophthalmology teaching that eye injuries are rarely caused by balls larger than 4 inches in diameter,483 the 8.6-inch diameter ball is responsible for approximately 80% of soccer eye injuries. Soccer eye injuries include serious injuries (hyphema, vitreous hemorrhage, retinal tear, chorioretinal rupture, angle recession), as well as minor corneal abrasions and contusions.27,123,484,485 Soccer-related eye injuries, the leading cause of sports eye injuries in Europe and Israel,486–489,804 tend to be severe, with one-third of all injured players suffering hyphema.28 There is approximately a 2% risk of eye injury during an 8-year career (see Table 3). Where soccer is played frequently, approximately one-third of all sports-related eye injuries are caused by the soccer ball.20
The kicked soccer ball has a mean velocity, which increases with experience, of 45.6 (14.0 mph (Fig. 28). Soccer balls that are used in games vary with age (ages 8 to 10, #3 ball 240 to 300 g; ages 11 to 13, #4 ball 330 to 390 g; over age 14 #5 ball, 420 to 480 g) and have sufficient energy that some are concerned about possible brain injury from repeated soccer ball headings,490 but the correlation of proper soccer ball heading with brain injury is uncertain.491 Correctly executed headers, not associated with globe impact, do not cause significant rotational acceleration of the head and are unlikely to cause retinal hemorrhage, but incorrectly executed headers might.492
It is now known that sufficient energy is transmitted from the large ball to the eye to result in retinal detachment and permanent vision loss in many injured eyes,493 because the ball deforms enough to enter the orbit between 7.5 and 8.7 mm, remains in the orbit 10m/s (longer than any other sportsball; see Table 7) and has a suction effect on the globe as it leaves the orbit. There is no correlation of eye injury with ball size and ball inflation.805
Because proper heading techniques are essential for brain and retinal protection, heading the ball should be discouraged for younger players. Goal posts should be stabilized and padded.494–496 Sports eye protectors that pass ASTM F803 for squash prevent contact of the ball to the eye and should be encouraged.
Since 1960, basketball has progressed from a largely noncontact sport into one where significant body contact is allowed, with a corresponding increase in injuries.497 Men's basketball is second only to wrestling as the cause of significant college sports eye injuries, with an 8-year probability of a significant eye injury to one of every thirteen players. Women's basketball has an incidence of significant eye injuries immediately behind women's lacrosse and field hockey, with an 8-year career injury probability of a significant eye injury to one in every 26 players (see Table 3). When all eye injuries are considered, approximately 1 in 10 college basketball players sustain eye injuries each year.409 Basketball was the leading cause of sports eye injury (22.2%) presenting to United States emergency departments (see Appendix 1), and was responsible for the majority (28.7%) of sports eye injuries at the Massachusetts Eye and Ear Infirmary.28
Over a 17-month period, 324 National Basketball Association (NBA) professional basketball players sustained 1092 injuries, of which 59 (5.4%) involved the eye. Most of the eye injuries were relatively minor abrasions, lacerations, contusions, corneal abrasions, and traumatic iritis caused by opponent's fingers or elbows striking the player's eye, frequently during aggressive play under the boards, but 3 of the players suffered orbital fractures and the injuries caused 9 players (15.3%) to miss games and 5 players (8.5%) to miss practices only. The incidence of 1.44 per 1000 NBA game exposures is difficult for most players to comprehend, but if the calculation is expressed as the fact that approximately 1 out of every 6 professional players suffered an eye injury in about 1.5 years of play, the risk is more apparent. Only one NBA eye injury (a periocular contusion) was caused by the ball, and only one injured player was wearing an eyeguard at the time when he received a laceration below the eyebrow, but no injury to the eye itself, when the eyeguard was displaced upward by a finger as this power forward was going up for a rebound.498
Avulsion of the optic nerve, usually caused by the force transmitted by the extended finger, was more commonly reported in basketball than any other sport.102,499–501 The avulsion mechanism is most likely that the extended finger or thumb causes an extreme anterior rotation and anterior displacement of the globe, with a concomitant dramatic increase in intraocular pressure, with further anterior displacement of the globe secondary to an increase in intraorbital pressure.502
Because of the possibility of ruptured radial keratotomy incisions503–505 or late LASIK flap dislocation,99 it is essential that players who have had incisional refractive surgery or LASIK be advised to wear protective eyewear for all practices and games. Adequate eye protection, recommended for all basketball players (and absolutely essential for the functionally one-eyed) would be achieved with protectors certified to ASTM F803 for basketball, which has a specification to prevent a finger from contacting the eye with the protector in place.
Football faceguards have been quite effective because they have resulted in an 80% to 90% reduction in facial injuries. However, single- and double-bar protectors offer incomplete protection to the face and facial injuries comprise approximately 10% of all football injuries.506,507
If all eye injuries (minor and serious) are considered, the rate of eye injury to Michigan State University football players was 4.1% per year.409 Serious eye injuries are much less common than minor ones, with an 8-year risk of 0.87%. Although the average team could expect only one serious eye injury every other season,508 there will be more than four less serious injuries each season, indicating that eye contact occurs often enough that polycarbonate visors (Fig. 29) should be considered for all and mandated for the functionally one-eyed. Unless supplemented with a polycarbonate shield or separate eye protection, all presently available football face protectors allow penetration of a finger through the mask with enough force to result in retinal detachment or visual loss to the injured eye.509,510
One hundred three of 150 female and male players in the Southern California Rugby Football Union were injured during the 1981–1982 season. There were 11 eye injuries, 32 injuries (including fractures) to other parts of the face, and 26 head injuries.511 Intentional eye gouging has resulted in giant retinal tears.512 Injury reduction by better conditioning, rules modifications, and adherence to the rules of the game has been emphasized.513 It is not known whether sports eye protectors certified to ASTM F803 will give adequate eye protection from rugby eye injuries.
Volleyball, Netball, Team Handball, Speedball, and Bombardment
These games also are responsible for some eye injuries, but the incidence is low for volleyball (see Table 3) and not known for netball, team handball, speedball, and bombardment at this time. Adequate protection would be achieved with the eye protectors recommended for basketball.
With 6 million participants (2.6 million frequent), the martial arts are the most popular combat sport, and the most popular among women, who represent 37% of the participants. Wrestling (94% male) involves 2.4 million (0.5 million frequent) and boxing 0.9 million participants.35 Because eye trauma is intrinsic to professional boxing and the full-contact martial arts, no eye protection is permitted or available. The helmets worn in amateur boxing and amateur full contact kick boxing give partial eye protection, but still permit contact of the glove to the eye, especially if the glove has a thumb that can be extended to the “hitchhiker position.” There are no standards for eye protectors for wrestling or the noncontact martial arts, but it would be possible to construct adequate protective eyewear, possibly attached to a soft helmet that would incorporate ear protection.
If the usual sources are referenced, it would appear that eye injuries from boxing are extremely rare. Only 34 of a total 37,005 eye injuries resulting from sports and recreational activities in 1990 were attributed to boxing by the NSPB.514 The USEIR captured only 4 boxing injuries: 3 retinal detachments (including one giant tear) in professional boxers, and 1 blowout orbital fracture sustained in an Army boxing match that resulted in 14 days lost from work.201 As an investigator looks through available databases, it soon becomes apparent that there is no national or even regional comprehensive source of data regarding the real incidence, severity, and long-term outcome of eye injuries from boxing.
Yet it is apparent to any ophthalmologist who has examined boxers that eye injuries as a direct result of boxing are very common. The ophthalmologists who actually care for the injured boxers have realized the following. Boxers tend not to be seen in hospital emergency departments because eye injuries are the accepted result of the sport and are usually “toughed out” with little or no treatment. Blinding injuries most often affect one eye, and the boxer will frequently hide the defect for fear of being disqualified from the sport. Other blinding eye injuries, such as glaucoma from angle recession, may occur many years after retirement from the sport and a correlation between the injury and the blindness will not be made or if made then not reported to any central monitoring agency. Thus, if the true incidence of eye injuries to boxers is to be ascertained, one must look to smaller studies that specifically address the problem rather than large databases that essentially ignore the sport.
Because Olympic and professional boxing are dissimilar sports, they will be considered separately.
Headgear is mandatory in Olympic boxing, yet eye injuries are not rare in this group. Of 13 Olympic boxers examined in 1984, 3 had retinal holes or tears, probably as a result of boxing, and 1 had an unrelated amblyopia that reduced his best-corrected vision in the amblyopic eye to 20/400.515 The incidence of eye injuries reported from the U.S. Olympic Training Center from 1977 to 1987 as 23 of 447 total injuries (5% eye injuries) with only 1 retinal detachment516 is almost certainly falsely low, because there was no systematic examination of the eyes of these boxers by an ophthalmologist that included dilated slit lamp examination, gonioscopy, and examination of the peripheral retina. There was a low incidence of eye injuries in a group of 20 active, elite, amateur, asymptomatic Turkish boxers among whom only one boxer had an atrophic retinal hole that was treated with laser prophylaxis.517
Military instructional programs, such as those at the U.S. Military Academy at West Point, are fashioned after the Olympic program. Although the total injury rate seems low (less than 4% injuries in 2100 cadets who received boxing instruction between 1983 and 1985), the incidence of eye injuries is impossible to evaluate because no asymptomatic participants had the benefit of an adequate ophthalmologic examination for this study.518 Twenty-two of 401 (5%) soldiers hospitalized for boxing-related trauma were admitted for eye injuries, with one eye enucleated after complications of a ruptured globe. This study did not examine all boxers and underestimates the incidence of eye injuries to boxers by only reporting those requiring hospitalization, not asymptomatic injuries that may cause problems after military discharge, unless adequate predischarge examination is done.519 The mere questioning of whether boxing should be banned from military training520 has resulted in heated debate.521–523 In response to mounting pressure from the medical community, the U.S. Air Force Academy has eliminated boxing as a mandatory activity.524 It seems reasonable that the military, with a captive population, would be the ideal arena to perform prospective studies of the true incidence of eye as well as other boxing injuries.
The most reliable studies of eye injuries in professional boxing involve complete eye examinations on relatively large groups of active boxers. Seventy-four asymptomatic boxers, in various stages of their active careers, were referred to the Sports Vision Institute of Manhattan Eye, Ear and Throat Hospital on a sequential basis by the New York State Boxing Commission over a 2-year period (February 1984 to February 1986). The boxers averaged 61 bouts with 8 losses over 9 years. Vision-threatening injuries (significant damage to the angle, lens, macula, or peripheral retina) occurred in 43 boxers (58%). Two boxers were actively boxing with best-corrected visual acuity of 20/200 in the injured eye. Retinal tears were directly related to the total number of bouts and the number of losses. Twenty-four percent of asymptomatic boxers had retinal tears. It was calculated by the authors that a boxer has a 20% chance of a retinal tear after 5 losses and a 90% chance of a retinal tear after 75 bouts.525 A New Jersey study of 284 boxers confirms the high incidence of eye injuries in boxing, with 19% of those dilated having retinal problems and 15% having cataracts attributable to the sport. Three boxers (of whom two were world champions) had their careers ended after the need for cataract extraction.526,527 The high incidence of boxing-induced ocular injuries was reconfirmed in a study of 505 professional boxers in whom there were 18% with retinal holes, 38.8% with angle abnormalities, and 5.9% with posterior subcapsular cataracts.528 There have been other series of retinal injury and detachment, as well as injury to the lids, lens, angle, and vitreous.529–535 Professional boxers, such as Sugar Ray Seales, have lost vision in both eyes.
There have been several proposals, which have resulted in state advisory boards establishing safety standards, to decrease the eye, brain, kidney and soft-tissue injuries, and deaths in boxing.536,537 Some believe that boxing should be banned in the United States, as it is in Norway and Sweden—a position vigorously opposed by others.538–546 Removing the gloves would deemphasize the knockout punches by making boxing a sport of jabs and defense,547 but would the exposed fingers and knuckles increase eye injuries? At this time, the most desirable changes would be those that not only increase public awareness of the dangers of boxing, but also make it safer for participants.548 The American Academy of Ophthalmology has a policy statement on reforms for the prevention of eye injuries in boxing, which would promote early diagnosis and treatment and prevent visual disability with recommendations that include (1) examination of boxers before licensure and then after 1 year, six bouts or two losses, or at the stopping of a fight because of an eye injury, or at the discretion of the ringside physician; (2) mandatory, temporary suspension from sparring or boxing for specific ocular pathology—30 days for a retinal tear and 60 days for a treated retinal detachment, or individualized after consultation with the athletic commission medical advisory board; (3) minimal visual requirements of 20/40 or better in each eye and a full central field of not less than 30 degrees in each eye; (4) an ophthalmologist required on each state medical boxing advisory board; (5) thumbless boxing gloves to minimize ocular injuries; (6) a national Registry of Boxers for all amateur and professional boxers in the United States that records bouts, knockouts, and significant ocular injuries; (7) a program for training and recertifying ringside physicians; and (8) a uniform safety code.549
Wrestling has the highest risk of eye injury for college sports, with approximately one in eight participants suffering a significant eye injury after an 8-year career (see Table 3). The USEIR database has five wrestling eye injuries, consisting of choroidal rupture, vitreous hemorrhage, retinal detachment, orbital fracture, and an open-globe injury caused by dehiscence of a corneal graft in a 16-year-old male who had a penetrating keratoplasty at the age of 8. The average college team with 25 players and 2600 athlete-exposures should expect one or two eye injuries each season with a significant injury every 9 or 10 seasons.550 At Michigan State University 18.4% of wrestlers suffered eye injuries that were relatively mild (lacerated eyebrows, corneal abrasions) and left no permanent damage.409 The case of a highly myopic (–12 diopters) teenaged young man who lost an eye to a giant retinal tear suffered while wrestling and who then continued to wrestle only to lose the remaining eye the following year to a giant retinal tear secondary to a wrestling injury551 emphasizes why wrestling is not recommended for one-eyed athletes.
Although headgear is required at NCAA competitions, and ear protectors can reduce ear injuries that result in the permanent deformity of cauliflower ear, 65% of Division 1 wrestlers do not wear headgear all the time during practice. This reluctance on the part of wrestlers to wear headgear, because of discomfort, compounded by the lack of a standard specification for wrestling eye protective devices, makes protection of the one-eyed wrestler problematic at this time. Some commercial wrestling face guards have large eye openings that readily admit eye contact by fingers. The protection afforded by custom face masks552 must be viewed with suspicion, because custom made face masks for ice hockey goalies have proven ineffective for the prevention of hockey eye injuries.
Herpes gladiatorum, caused by herpes simplex type I, is easily spread through skin-to-skin contact.553 Sixty of 175 wrestlers (34%) attending a 4-week intensive training camp developed herpes simplex type 1 infections. Five of the 60 (8%) in the third or fourth week of camp developed primary ocular herpes infections that included follicular conjunctivitis, blepharitis, and phlyctenular disease but no corneal involvement or late ocular recurrence. All responded to topical vidarabine ointment five times per day or trifluridine drops every 2 hours.554 By preventing the virus from reaching the blister stage with the use of oral acyclovir as soon as the wrestler feels an itching or tingling sensation, especially at the site where blisters have developed before, the wrestler can reduce the course of the disease from 2 weeks to 2 days.555 Because virus can be recovered up to 4 days after crusting of vesicles, it is recommended that athletes refrain from contact for 5 days after the lesions have dried and crusted.556
The incidence of eye injury in the martial arts is unknown and there are no standard specifications for eye protection for amateur participants. The two eye injuries from karate in the USEIR database, a periocular laceration and a fractured orbit, both were caused by errant kicks.
Swimming is used as a fitness activity by 15.3 million Americans. More than 69 million use various types of watercraft, 8.3 million water ski and 2.7 million scuba dive.35 UV light and irritation are a problem for all who engage in outdoor water sports. Surfers have a high incidence of pterygia and pingueculae that could be prevented by decreasing the UV light to the eye with sunglasses, where possible.557
Swimming and Surfing
Immersing the cornea in water produces approximately 42 diopters of hyperopia and an unaided visual acuity near 20/4000 (6/1200).558 For humans to see clearly underwater, the only alternative to placing a strong spherical lens (64.5 diopters in air) in front of the eye is to place an air space in front of the eyes. Into this air space, the fine tuning of any preexisting ametropia may be obtained with contact lenses, various types of spectacles, or lenses ground or bonded to the front or rear surface of the goggle (Fig. 30).559 Swimming stroke parameters are affected by visual impairment.560 Significantly ametropic competitive swimmers have better judgment of critical racing turns, can see competitors, and have visual communication with coaches if their ametropia is corrected. Several goggle and goggle-cap combinations that incorporate prescription lenses are available.561 It is important that lifeguards have proper scanning techniques562 and good vision.
Because surface swimmers breathe through both nose and mouth, most prefer goggles with elastic straps rather than face masks that interfere with breathing through the nose. Goggles protect the eyes from chemical irritants and provide the swimmer with better vision in the water. However, swim goggles have several potential safety problems. Ruptured globes, hyphema, and avulsion of the optic disc have been reported, in which the goggle was stretched from the face to be cleared (Fig. 31), then slipped from the wet hands of the swimmer and rebounded toward the eye(s); propelled by the elastic band, the exposed sharp plastic goggle edge then cut open the eye(s).107,563–567 Pressure on the trochlea from badly fitting goggles may interfere with action of the superior oblique and result in diplopia that takes several weeks to clear.568 This hazard could be reduced by better molding combined with fastening the goggle with a less elastic band that has an easily adjustable tightening mechanism, such as Velcro strips. Any goggle in which the foam comes loose from the plastic lens should be replaced. Unpadded goggles may cause eyelid deformities and neuromas,569–571 and goggles with tight straps have precipitated migraine headaches572; goggles with eye cups smaller than the orbital opening may raise the intraocular pressure by directly pressing on the globe.573 Because goggles are rigid, the pressure in the goggle is equalized during descent by the movement of the eye and surrounding soft tissues into the air space of the goggles. Because of the possibility of capillary rupture and hemorrhages, the largest goggles should only be used to a depth of 6 feet, and the smallest goggles to a depth not exceeding 11 feet. Deeper than 11 feet, the surface diver should use a diving mask in which the pressure may be equalized with air from the nose.574 Alcohol-containing antimisting agents must be completely dried before use, or acute corneal erosion may result.575
Caution must be exercised with use of contact lenses during water sports. Although almost all swimming pools are contaminated to some degree with coliform bacteria, and Pseudomonas occasionally is found in pool and ocean water, infection does not seem to present a great hazard to conscientious soft-lens wearers,576 but the risk of Acanthamoeba keratitis is most likely in those who wear contact lenses while swimming.577 Inadequately chlorinated (below 0.3 ppm) pools account for 30% of all failures of swimming pools to comply with standards for fecal coliform counts, with the greatest failure rate (44.6%) in public wading pools.578 Because of the rich microbial potential involved in the water sports,579 daily wear disposable contact lenses would be safer. Contact lenses that are left in the eye(s) overnight are not recommended. Swimmers who wear soft contact lenses in swimming pools can avoid lens loss by splashing pool water into the eye(s) with the lenses for approximately 1 minute so the lenses become hypotonic and adhere to the cornea. The osmotic bond lasts at least 30 minutes after exiting the pool; thus the corneal epithelium may be denuded if the lens is removed before that time, unless the osmolarity is equilibrated with normal saline drops for 15 to 20 minutes. Ocean water, on the other hand, has a high osmolarity, causes soft lenses to move excessively, and results in a high loss factor.576,580
Marine envenomations can result in severe systemic reactions and death.581 The most common eye envenomations are from jellyfish, which result in a keratitis and iritis with good prognosis.582–584 Leech and vibrio infestation from swimming have been reported.585,586 Goggles or divers masks would provide significant protection.
In surfing, head lacerations and broken noses, from the board striking the surfer, are the most common forms of injury. Eyebrow lacerations are relatively common, and blunt eye trauma is rare in surfing.557–588
The most common injuries in water polo are facial lacerations and broken fingers. One high school player lost an eye. Eye injuries can occur from elbows or fingers or be caused by the ball, which is about the size of a volleyball, thrown in excess of 40 mph.589 Swim goggles for water polo should be made of polycarbonate for impact resistance.
For high diving, significantly ametropic divers who have difficulty seeing the water or pool edge could wear hard, soft, or gas-permeable lenses. The loss rate is much lower than might be expected because divers instinctively close their eyes as they enter the water.558 Diving from extreme heights (50 feet) can result in contact and significant injury to the eye from the diver's fingers.105
Deep diving consists of hard-hat diving (essentially limited to commercial use), skin diving (mask plus snorkel), and scuba diving (mask plus self-contained underwater breathing apparatus). For every 33 feet of descent, the absolute pressure increases by one atmosphere (15 psi) and the surface volume of gas in goggles or a face mask diminishes to 50% at 33 feet, 33% at 66 feet, and 25% at 99 feet. If a diver is wearing a face mask, the air-containing space in the mask must be equalized with the ambient water pressure (by exhaling through the nose) on descent. Failure to equalize the pressure will result in face-mask barotrauma (conjunctival injection, hemorrhage, facial bruising, epistaxis).590–594 Because the only means for equalizing the pressure with rigid goggles during descent is the movement of the eye and surrounding soft tissues into the air space of the goggles, a diving mask, rather than rigid swim goggles, should be used for dives deeper than between 6 feet (larger goggles) and 11 feet (smaller goggles).574 Barotrauma from deep (20 meters) dives may result in orbital hemorrhage.595 Breath-holding diving has been associated with central vein occlusion.596
Because of the absorption of sunlight in water (blue light transmits further in the water than the longer wavelengths), there is a color shift as the longer rays of light are sequentially absorbed—red at 15 to 20 feet, orange then yellow at about 30 to 50 feet, greens at 100 to 120 feet where everything looks blue and becomes deeper blue-violet as the depth increases. The hard-hat diver may use spectacles that should have straps or cable temples to prevent dislodgment. Polymethyl methacrylate hard contact lenses cause corneal epithelial edema during the decompression phase of the dive by the trapping of nitrogen outgassing from the cornea and precorneal tear film. The resultant ocular discomfort, halos, specular highlights, and decreased visual acuity during and after the decompression phase may be hazardous to the diver. Soft and gas-permeable contact lenses do not result in gas trapping or corneal edema and are probably safe.597,598
The best, most practical method to correct ametropia for skin and scuba divers is to bond their corrective lenses with optically clear epoxy to a standard oval face mask made of tempered glass (see Fig. 30).559 Contact lenses may be worn under a mask, but they may be dislodged if the mask is flushed with water or in an emergency situation. Because displacement of the contact lens may further impair the diver faced with an emergency, contact lenses are not recommended for snorkel or (especially) scuba divers.598 Hollow orbital implants made of silicone may implode; thus solid implants or hollow glass implants (which withstand at least 4.5 atm of pressure) should be used for those divers who happen to require enucleation and wish to continue diving after surgery.599 The visually impaired, and even the totally blind, are able to scuba dive with the help of specially prepared equipment and reliable diving partners.600
The United States Olympic Yachting Committee found that 23 of 44 Olympic yachting hopefuls had pterygia. Many sailors complain of constant eye irritation, the result of wind and salt spray combined with UV keratitis. Polycarbonate wraparound, UV-light–absorbing sunglasses (which may be clear or tinted for comfort) relieve most symptoms and provide eye protection from impact with lines, spars, and so on. Competitive sailors are advised to wear a small spray bottle on a short cord around their necks. Fresh water from the bottle is used to clear the sunglass lenses and rinse salt buildup away from the eyes.601
Water skiing may be more hazardous for those in the boat than for the skier. Massachusetts state law states that there must be two persons in any boat towing a water-skier. The person who is watching the skier can be thrown from the boat if an unseen wake is struck. Three skiers suffered severe lacerating injuries to the face and upper extremities when they fell from the tow-boat and were run over by the propeller.602 A tow-boat driver lost an eye when the barefoot water-skier he was towing lost his balance, fell into the water, and let go of the tow rope, which was under a good deal of tension. The metal-reinforced handle of the tow rope snapped forward with such force that a ruptured globe and extensive fracturing of the right orbit occurred.603
Jet skis may be dangerous to the rider as well as the swimmer. Most injured riders are younger than 15 years old. Life jackets, helmets, age limit to 16 or over, and prohibition of jet skis from swimming areas would decrease injury and death.604 Personal watercraft injuries have increased fourfold between 1990 and 1997. Specific training, adult supervision of minors, and personal flotation device use would help prevent these injuries.605
Cycling and the Motor Sports
Cycling, nonmotor, and the motor sports are significant causes of visual problems from intracranial injuries to the optic nerves, chiasm, and optical pathways from extreme impact energy to the head. BMX bikers are primarily males (74%) in the 6 to 17 year age group, Of the 3.7 million BMX bikers, 1.1 million participate more than 52 times per year. Mountain biking participants number 7.4 million (70% male, 1.7 million more than 25 times per year). Bicycling as a primary fitness program involves 1.9 million (52% females), and there is a huge, uncounted population of recreational cyclists and motorcyclists. Snowmobiling has 6.8 million participants (56% male, 1.5 million more than 15 times per year).35
Each year, approximately 900 people in the United States are killed by bicycle crashes, which occur once for approximately every 4500 riding miles. Of the 567,000 (350,000 under age 15) emergency department visits because of bicycle injuries, 130,000 were to the head.606 Eye injuries, including ocular contusion injuries, luxation of the ocular globe,607 foreign bodies, traumatic optic neuritis,608,609 result from flying debris, crashes, and falls. The USEIR database has six eye injuries: one open-globe from falling on a stick, one shot with a BB while riding a bicycle, two serious lid lacerations, one orbital fracture, and one vitreous hemorrhage.201 Cyclists, especially children who suffer the majority of serious head injuries from bicycling accidents, would avoid most head, face and eye injuries if they wore adequate head protection whenever they rode. Bike helmets reduce the risk of head injury by 85%. The universal use of helmets by all bicyclists would prevent one death every day and one head injury every 4 minutes.610–618
A layer of stiff foam in the helmet reduces the peak energy of a sharp impact by crushing. The spongy foam inside a helmet is for comfort and fit, not for impact. The helmet should be brightly colored for visibility and must fit level on the head, touching all around, comfortably snug but not tight. The helmet should not move more than about an inch in any direction, and must not pull off no matter how hard the cyclist tries. A helmet should not have: snag points sticking out, a squared-off shell, inadequate vents, excessive vents, an extreme “aero” shape, dark colors, thin straps, complicated adjustments, or a rigid visor that could snag in a fall.
A sticker inside the helmet tells what standard it meets. Helmets made for U.S. sale after 1999 must meet the U.S. Consumer Product Safety Commission standard. ASTM's standard F–1447 is comparable. Snell's B–95 and N–94 standards are tougher but seldom used. The weak ANSI Z90.4 standard is inadequate. Replace any helmet if you crash. The Bicycle Helmet Safety Institute (http://www.bhsi.org/), from which the above paragraphs were abstracted, constantly updates helmet information.
Many cyclists have constant gritty eye irritation from wind and sun exposure, especially when traveling at high altitude in arid regions. Although a lubricating ointment will give temporary relief from dry eye symptoms, the best protection is a good pair of polycarbonate lenses that shield the eyes from dust, dirt, wind, and UV light. Eye protection certified to the high-velocity/high-mass specifications of ANSI Z87, the specifications of ASTM F803, or the military eyewear fragment specification would protect from flying road debris and would add to the protective effect of the helmet for the eyes in case of a crash.
Most bicycle injuries could be prevented if bicyclists: (1) avoid loose sand or gravel, especially when turning or going downhill; (2) avoid riding double; (3) properly maintain their bicycles; (4) wear protective clothing, including helmets; (5) obey basic traffic laws; and (6) use lights and reflectors and wear light-colored clothing.619,620 Cyclists should be separated from motor vehicles as much as possible and children should delay cycling until developmentally ready.621 Long, competitive races require an extensive medical support network with safety regulations, such as the mandatory use of helmets. The US Cycling Federation (USCF) requires that riders wear helmets. In 8 years of competition, 606 riders broke many helmets in crashes each year but only two serious head injuries were recorded.622
Common to most vehicles is the storage battery, which can explode and cause open-globe injuries, surface and intraocular foreign bodies, and chemical burns.623–628 Strict adherence to Prevent Blindness America jump-start instructions could prevent almost all battery explosion eye injuries, which also could be life saving if the vehicle is an all-terrain or snowmobile in a remote location. To safely jump-start a dead battery:
Batteries explode because a spark ignites the hydrogen gas that is often present in the vicinity of a battery and in the battery cells. Remembering that the last connection in the jump start sequence always sparks, and that the last connection is always to a ground away from the potentially explosive hydrogen gas will help one remember the proper sequence. Safety goggles and the jumper cables should be kept together.
The vast majority of all-terrain vehicle accidents involve males younger than the age of 30. Because of the high incidence of injuries to the face and head, and accidents associated with poor judgment and alcohol, protective headgear, as well as training and abstinence from alcohol while driving, are advised.630,631 Because of increasing catastrophic spinal injuries to children, it has been suggested that the use of off-road vehicles should be limited to those who hold a valid driver's license or who have passed a test certifying that they understand the risks associated with these vehicles.632 Helmets with integral face and eye protection would decrease the incidence of facial fracture and ruptured globes.633
Championship Auto Racing Teams (CART) have an accident frequency of 1 per 1414 miles of racing with 1 injury per 9.5 accidents. The rate of accidents at the Indianapolis Motor Speedway is less at 1 per 3000 miles raced, but the frequency of injury was higher at 1 injury per 3.2 accidents. Despite speeds of 200 mph, most automobile racing injuries are limb, rather than life, threatening.634 This is because of sophisticated race car design and safety equipment, which includes a driver's helmet in compliance with the Snell Institute standards,635 fire-retardant clothing, restraining harness, fire extinguisher system, and (optional) compressed air supply to create positive pressure within the helmet to keep out smoke and fumes.636 The combination of high gravitational forces plus harness compression in car-flipping accidents has resulted in acute retinal angiopathy, with minimal injury elsewhere, to five drivers. Although good visual acuity recovered, these drivers had evidence of permanent retinal vasculature and anatomic changes that resulted in scotomas, color vision defects, and changes in contrast sensitivity.637 Considering the magnitude of the forces involved, it appears that the potential for eye injury has been reduced to an acceptable minimum with present safety equipment.
Mandatory helmets reduce head injuries to motorcyclists.638–641 Faceguards attached to the helmet add a significant degree of eye and face protection.642 Motorcycle goggles decrease the incidence of pingueculae, pterygia, keratitis, and ocular foreign bodies in motorcycle riders643,644 (Fig. 32). The U.S. Supreme Court in the 1972 case of Simon v. Sargent upheld the concept that society has the right to mandate protective equipment that appears, on the surface, to affect only the individual. “From the moment of injury, society picks the person up off the highway; delivers him to a municipal hospital and municipal doctors; provides him with unemployment compensation if, after recovery, he cannot replace his lost job, and if the injury causes permanent disability, may assume the responsibility for his and his family's subsistence. We do not understand a state of mind that permits a plaintiff to think that only he himself is concerned.”645
Most eye and facial injuries to snowmobilers can be avoided by a combination of safe driving, avoidance of alcohol and drugs while driving, and full-face protection.646,647 Protection against snowblindness and ocular windburn is available with shatter-resistant face masks or goggles. As more snowmobilers are wearing head and face protection, the leading anatomic site of injury, in Wisconsin, shifted from the head and face to the extremities over 15 years.648
Other Active Sports
Exercise, Running, and Jogging
Elastic cords (used for repetitive resistance exercises) may snap or release from a handle or hook and cause an eye injury.649 The rapid deceleration associated with bungee jumping causes a sudden rise in intraocular pressure and intravenous pressure that may cause retinal hemorrhage650–659 and orbital emphysema.660
Eye injuries to runners and joggers usually result from striking branches, twigs, pipes, and so on while running in low light conditions in unfamiliar terrain. In sports, retinal detachment is usually caused by direct trauma to the globe.86 Physical activity such as running and jogging do not increase the incidence of retinal detachment.661,662 Bird attacks, which caused a fatal accident to a bicyclist in Melbourne, usually are from birds of prey attacking the runner from the rear. Scalp lacerations, but no eye injuries, have been reported. Fake eyes affixed to the back of a jogger's cap may discourage a bird attack to the jogger or runner.663,664
Inverted posture may be hazardous to some participants. The practice of hanging upside down by means of “gravity boots” was associated with a retinal tear in a highly myopic patient.665 Inverted posture raised the intraocular pressure from a preinversion average of 19 mm Hg to an average of 35 mm Hg after inversion for 3 minutes; this returned to normal within 1 minute after seated posture was resumed.666 Glaucomatous patients experience a higher rise in pressure to 37.6 mm Hg ± 5.0 after inversion for only 30 seconds. The inverted posture probably raises intraocular pressure by increasing episcleral venous pressure, which is closely related to increased venous pressure in the orbit. The episcleral venous pressure rise almost immediately follows posture inversion, with a typical normal subject's pressure, normally 16 mm Hg sitting, increasing to 27 mm Hg after 10 seconds of inversion, then increasing to 32 mm Hg within 30 seconds, after which it remains unchanged.667–669
Patients with ocular hypertension, glaucoma, and retinal vascular disease should be discouraged from maintaining the inverted posture that doubles the intraocular pressure and the diastolic ophthalmic artery pressure; increases the systolic ophthalmic artery pressure by 60%; constricts the retinal arterioles; reduces pattern reversal visual-evoked potentials; and causes transient visual field defects in many subjects.670,671 Yoga exercises that use the shoulder-stand and headstand positions may contribute to field loss in glaucoma patients by significantly elevating the intraocular pressure while the participant is in the inverted position.672
Although the inverted posture may be harmful to those with glaucoma, other forms of exercise can be beneficial. Regular aerobic exercise is associated with a reduction in intraocular pressure and may represent an effective nonpharmacologic intervention for patients suspected of having glaucoma.673–680 However, some young patients with advanced glaucomatous optic neuropathy may experience exercise-induced visual disturbance from an exercise-induced “vascular steal.” These patients should be advised to limit activities which induce their symptoms.681
Patients with glaucoma with pigment dispersion syndrome may experience symptomatic elevation of intraocular pressure (to 47 mm Hg) after strenuous exercise, such as playing basketball for 2 hours. Pretreatment with 0.5% pilocarpine 30 minutes before the physical exertion prevents the pressure spike and the pressure lowers, as is usual in patients with glaucoma who do not have pigment dispersion. Pressure rises in those with pigment dispersion occur with exercises that involve jumping or jogging for several hours,682 but not after comparable periods of equivalent cycling. It is believed that the jumping increases iris-zonule contact, which is prevented by pretreatment with pilocarpine.683 Neodymiun:yttrium-aluminum-garnet (Nd:YAG) laser iridotomy prevents the bicycle ergometer induced iris concavity that results in pigment dispersion in some patients.684
Topical timolol (a nonselective β1- and β2-blocker) interferes with exercise endurance probably by reducing the maximal obtainable heart rate.685 It is interesting that topical betaxolol (a selective β1-blocker) does not cause this side effect, despite the fact that betaxolol is a potent β-blocker when administered systemically. There is most likely insufficient active drug in the blood after ocular administration to cause a measurable cardiac effect in normal persons. It would be prudent to attempt glaucoma control with betaxolol rather than timolol in those patients with glaucoma who require a β-blocker but also happen to be endurance athletes.686
Weightlifting may cause extreme blood pressure elevations during and immediately after exertion. Five experienced body builders had a mean elevation of blood pressure to 355/281 mm Hg, with one subject reaching an alarming 480/350 mm Hg after a series of double leg presses. Even a series of single arm curls raises the mean blood pressure to 293/230 mm Hg. Subarachnoid hemorrhage explained severe post-weightlifting headaches in two women, aged 16 and 25.687 Patients with vascular eye disease in whom acute, severe elevations of blood pressure may be harmful, should train with lighter weights, using more repetitions.
Frisbees typically cause lid lacerations and hyphemas, but there is at least one open-globe injury from shattered sunglasses that had glass lenses. Injuries to the eye can be avoided with shatter-resistant eyewear. It is probably impossible to make a Frisbee eye-safe without destroying desirable aerodynamic characteristics.
Mountaineers at altitudes higher than 12,000 feet (3658 meters) are subject to retinal hemorrhages, probably secondary to hypoxic vasodilation combined with sudden rises in intravascular pressures. The hemorrhages resolve spontaneously with return of normal visual acuity on return of the climber to a lower altitude, but the climber may be left with permanent reduction in critical flicker fusion frequency, visual fields, and dark adaptation.196,688–690 One climber, on a Mount Everest ascent to 5909 meters, had a permanent visual loss to finger counting after an ischemic central retinal vein occlusion with vitreous hemorrhage. Higher baseline intraocular pressure and the use of nonsteroidal anti-inflammatory drugs are risk factors for the development of altitude retinopathy.691 The severity of high-altitude retinopathy is correlated with potentially fatal high-altitude cerebral edema and progression of both conditions may be prevented with oxygen, steroids, diuretics, and immediate descent.692 Hemoconcentration and hypoxia—the underlying factors of acute mountain sickness, high-altitude cerebral edema, pulmonary edema, thromboemebolism, and high-altitude retinopathy—should be treated in patients with high-altitude retinopathy.693
A 77-year-old man with low endothelial cell counts developed endothelial decompensation necessitating a penetrating keratoplasty when he drove to 12,500 feet.694 A 15-year-old boy had the transient loss of light perception secondary to the expansion of a perfluoropropane gas bubble used to treat a giant retinal tear when he was driven over a 4289-foot mountain pass.695 Because this ascent is comparable to that of commercial airline jets reaching cruising altitude in which the cabin pressure is the equivalent of approximately 7000 feet, patients with intraocular gas bubbles risk significant elevation of intraocular pressure because of expansion of the intraocular gas and probably should remain at lower altitudes and avoid aircraft flight until the bubble diminishes in size.696
The prevention of snowblindness secondary to overexposure to UV light is essential. Because the thinner atmosphere does not filter out as much of the sun's UV light as does the thicker atmosphere at sea level, and ice and snow reflect approximately 85% of UV light, the climber is twice exposed by both direct and reflected UV light. A severe case of snowblindness may be asymptomatic for 8 to 12 hours after exposure, then be totally disabling for several days while the climber is unable to keep the eyes open because of extreme pain, photophobia, and lid edema. Mountaineering sunglasses or goggles should filter out at least 90% of wavelengths below 400 nm and be designed to block most reflected light coming from the sides and below. In an emergency, goggles may be made of cardboard with a thin slit. Sherpa and Balti porters have been known to protect their eyes by pulling their hair down over their faces. Mountaineers should understand that UV light protection is as important under overcast conditions as it is in full sunlight. Erythropsia (vision that is temporarily tinged red) is the result of retinal overexposure to UV light and can be eliminated by the use of UV light-absorbing glasses.697,698
Eyes that have radial keratotomy are prone to significant hyperopic shift that can impede vision and increase mountaineering risk.699–704 Eyes that have had LASIK or photorefractive keratectomy to treat myopia are less prone to visual fluctuation at high altitude, usually from a myopic shift.702,705,706
There are more than 1.2 million horse owners younger than age 20 and more than 27 million riders older than age 12 in the United States. Horseback riding is an extremely diverse sport including dressage and show jumping in arenas, cross-country endurance, fox hunting through wooded trails, 24-hour mountain endurance races, tetrathlons (races that combine riding with running, swimming, and shooting), calm trail riding, rodeo, polo (discussed in prior section), racing on horseback or while mounted or in a sulky, activities for the handicapped, and the formal moves of the Spanish Riding School of Vienna.707
Approximately 20% of equestrian injuries are to the head and face. There are between 105 and 257 deaths per year, mostly as a result of head injuries, a number that could be greatly reduced by the universal use of headgear that stays on the head in accidents, resists penetration, and prevents transmission of concussive forces.708–712
The risk of injury in U.S. Pony Club (USPC) events in order of decreasing incidence is cross-country, horse/pony jumping, stadium jumping, dressage, hunter equitation, pony club games, gymkhana, hunter, and vaulting. The USPC has required mounted members to wear hats that have passed protective standards since June 1, 1983.708 Protective standards have become more stringent with the advent of the ASTM standard Fl163 specification for headgear used in horse sports and horseback riding in 1990. Helmets are tested to the standard and independently certified by the Safety Equipment Institute (SEI). As more riders wear headgear that bears the SEI seal, it is expected that injuries will continue to decrease.713 Most USPC riders face and eye injuries result from jumping. The increased size of the ASTM helmet, which acts as a buffer, taking impacts first before they reach the face, has resulted in a decrease in eye and face injuries in USPC riders.714 From 1990 to 1992 the USPC reported a decrease in head injuries by 26% and in face injuries by 62%.715
The mandatory use of helmets and face guards to prevent concussions and facial injuries in rodeo events that involve large animals is controversial,716,717 but more bull riders, the competitors most likely to suffer head and face injury,718,719 are voluntarily using the protective headgear.
Both cross-country and downhill skiers can suffer ski pole injuries720 and snowblindness. Two perforated globes as a result of skiing were reported to NETS. The first occurred in a skier who was not wearing glasses or goggles and was struck in the eye by a piece of plastic on the end of a cord. The second occurred when a street-wear spectacle lens shattered on impact from the handle of a ski pole. Serious periocular injuries have occurred when ski goggles shattered. Ski eyewear should conform to the high-impact requirements of ASTM F659.
One death occurs per 1.6 million Alpine skier days. The fact that 82% of deaths involve head injuries, and that deaths are extremely rare in downhill ski racers who are required to wear helmets,721 indicates that unniversal use of helmets would greatly reduce skiing deaths.
SLEDS, TOBOGGANS, SNOWBOARDS, AND TUBES.
The incidence of eye and face injuries in these sports is unknown. It is believed that tubing may be the most dangerous of winter sports.722 The close proximity of participants, excessive speed on slopes that are too steep, and fixed objects, such as rocks and trees, account for the majority of collision injuries.723 Luge does not pose a significant eye injury hazard but is responsible for severe post-run headaches in the majority of participants. Although the cause of lugers' headaches, possibly due to the strain of holding up the head aggravated by jolts from an uneven track, is not yet known, they seem not to have permanent adverse effect.724
|The year 1976 was a turning point for blind athletes: the United States
Association for Blind Athletes (USABA) enabled blind and partially
sighted athletes to participate in competition on a national level, and
the Olympiad for the Physically Disabled was the first Olympiad
with full competition for blind, paralyzed, and amputee athletes.725,726 Events included track and field, gymnastics, wrestling, the 10-kilometer
run, and goal ball—a fast-paced game developed
especially for blind athletes in which a 4.5-pound ball containing
bells is rolled on a 30 × 60 foot mat, past opposing players, across
an end. To eliminate the advantage the partially sighted may
have over the totally blind, all players, including the totally blind, wear
blindfolds for the game. Athletes of all ages are divided by vision
into three groups: Class A, totally blind or light perception with
no acuity, with less than three degrees of visual field; class B, 20/400 or
less with 3 to 10 degrees of visual field; and class C, less than 20/200 and/or
between 10 and 20 degrees of visual field.|
As a result of encouragement from organizations such as the USABA, the blind are participating in more active sports—such as beep baseball, tandem cycling, golf, downhill and cross-country skiing, skating, wrestling, judo, track, and swimming—in addition to the usual activities of the blind such as bowling, nature hikes, boating and fishing, picnics, and dances. Beep ball was invented by the Telephone Pioneers of America and uses a sound-emitting soft ball with sound-emitting bases. All players wear head, face, and chest protection. The sport is so popular that the National Beep Baseball Association drew a crowd of 1200 spectators at a national tournament.727 The US Blind Golfers Association (USGBA) is the oldest organization that promotes organized sport for totally blind athletes. Ski for Light, the Blind Outdoor Leisure Development (BOLD), and the American Blind Skiing Foundation promote skiing for the blind.
The sports achievements of the blind are impressive: Harry Cordellos, blind from diabetes, completed the Boston Marathon in under 3 hours with the help of a sighted companion. Craig MacFarlane is competitive with sighted golfers. Sky-diver Tom Sullivan pulls the rip cord at the signal (by helmet radio communication) from his sighted sky-diving companion. Tom O'Connor completed a triathlon in the remarkable time of 3:49:06 without being tethered to a guide. For the 0.9-mile swim, he swam in a lane formed by 20-foot tubes pulled by a kayak, he ran 6.2 miles with a guide alongside him, and cycled 25.1 miles guided only by verbal commands shouted from a guide car.
It is important to encourage those who become partially sighted or blind to pursue sports activities through one of the many organizations that are expert in promoting active sports that are challenging, and safe, bolster self-esteem, and especially are fun.728–732
|VISION PERFORMANCE AND TRAINING|
|The use of visual training to improve athletic performance is increasing
in popularity as more practitioners enter the field. The controversy
surrounding visual training and athletic performance does not center
around whether visual parameters that are not commonly measured—such
as dynamic visual acuity (visual ability with the athlete, the
object of regard, or both, in motion), eye tracking ability (the
ability to maintain fixation on a moving target), glare recovery, visualization (the ability to see an image in the mind's
eye), visual concen-tration (the ability to concentrate on the visual task at hand and exclude distractions), central-peripheral field awareness (the
ability to be aware of or even concentrate on objects
or players eccentric to fixation), speed and span of recognition (the
ability to see, often separate, objects quickly and accurately) and
quiet-eye time (the release of fixation on a target after the brain has sufficient information for the body to react appro-priately)—are important for athletic performance, they clearly are. Yet to be determined is whether visual training can improve athletic performance, and, if so, what training is
Personal observations of one-eyed athletes raise questions about some of the current concepts of visual performance and vision training and suggest areas for future research. Many people with severe limitations of vision in one eye function at the highest levels of sport in which it is commonly assumed that true stereopsis is essential. A few examples are: after enucleation of his dominant eye, a flight instructor continued a demanding career flying airplanes; a trap shooter remained a top competitor after losing sight in his dominant eye; a semi-professional baseball pitcher lost an eye to a line drive, then successfully continued his career; a high school athlete lost an eye playing basketball, then excelled in college varsity baseball, football, and basketball; a football quarterback with dense amblyopia who also played basketball and baseball for a major university excelled in all three sports; a Major League outfielder was an excellent batter despite mild macular degeneration and 20/30 vision in each eye with no measurable stereopsis. How can these players and others (such as Babe Ruth who had dense amblyopia) perform so well without vision skills that are usually considered essential for performance? Hitting a baseball is considered one of the most demanding athletic tasks, yet five of the seven athletes mentioned above were able to play baseball at college, semi-professional, and professional levels without true stereopsis. A trap shooter, compensated for loss of his dominant eye in a sport in which sighting with the dominant eye is considered essential.
Studies on the physics of baseball and the visual activity of baseball batters give insight into the timing required to hit a baseball.465,733 The motion analysis of Mark McGuire's 70th home run in St. Louis on September 27, 1998, is depicted in Figure 33. The ball left Carl Pavano's hand at 106 mph and slowed to 96 mph in the 0.4 seconds it took to reach home plate. McGuire had his front foot off the ground as the ball was released, started his swing when the ball was halfway to the plate, and was essentially fully committed to the path of the swing when the ball was still 21 feet from home plate. The 34.5 inch, 33-ounce bat had a tip speed of 80 mph when it collided with the ball and propelled the ball at 110 mph with 2000 rpm back spin for a home run. Pavano, throwing the ball on the same initial trajectory, could have placed the ball almost anywhere in the strike zone by varying the speed and spin on the ball. Figure 34 relates the ball speed, the ball revolutions per minute (the revolutions of the ball between the pitcher and home plate are in parenthesis), the direction of ball spin as viewed by the batter, and the final position of the ball in the strike zone. With all of these final ball positions possible from the same release point and the same initial trajectory, it was essential that McGuire predict the type of pitch to by thrown by analyzing both the speed and spin of the ball as Pavano was going through the delivery motions—before the ball was even released. A swing timed to hit a home run off of a 91-mph fastball will miss a 96-mph fastball completely. Minor variations in Pavano's delivery and arm speed would be a clue as to the ball speed. Seeing the grip Pavano had on the ball at the time of release would be a clue as to the type of spin the ball would have. McGuire did all of this subconsciously at the visual-motor memory level—the reflex reaction of an excellent batter. All batters analyze pitchers, their delivery, and the pitches they usually throw, but no batter I know of has said they consciously analyze any of this while at bat. They simply hit the ball with the bat.
To see how the ball is held in the pitcher's hand requires good visual acuity. Perhaps one reason that baseball batters usually have excellent static visual acuity (81% better than 20/15) is that good visual acuity is necessary to predict where the ball will be when it crosses home plate. Distance stereo-acuity and contrast sensitivity, which also measure significantly better in professional baseball players than the general population also probably play a major predictive role in final ball position.734 If we put baseballs on thin poles, one 29 feet from home plate, and the other 30 feet from home plate, the batter cannot tell which ball is further away, unless one ball hides part of the other. As the ball approaches the plate, the angular velocity in relationship to the batter's eyes increases rapidly, so that when the ball is within 10 feet of the plate, the angular velocity exceeds 500 degrees per second and is impossible to track. The maximum smooth pursuit velocities in professional baseball players are 30 degrees per second for the head and 130 degrees per second for the eyes In the initial tracking of the ball, it has been shown that professional batters move their head as well as their eyes to track the ball as long as possible.733
McGuire was probably using distance stereopsis, but he was not using (usually measured and trained) near stereopsis to any significant degree when he started his swing. He was tracking the ball, moving both his head and his eyes until tracking became impossible within ten feet of the plate. Distance stereopsis could be used to modify the plane of his swing until the ball was 10 feet from the plate, but changing the plane of the swing after the batter has transferred energy to the bat at about 20 feet is very difficult.
Accommodation and convergence are too slow to have played any role in hitting the ball. The image was 34 degrees off McGuire's fovea when the ball was two feet in front of home plate. It is apparent that McGuire could hit a very blurry baseball out of the park because he has the gifts of natural ability and superior motor memory that have been fine-tuned with practice. If McGuire were rigidly trained to keep his head still and track the ball to the moment of contact from an early age735 and he rigidly followed these instructions, he probably would not be very good at hitting a baseball. When we train athletes, we must be certain that what we are teaching actually will help and not interfere with performance. Analysis of many photographs of athletes hitting balls or pucks with bats, rackets, or crosses show that they almost never are looking at the point of contact between the ball and the racket, bat, stick, or crosse. It clearly is detrimental to performance to instruct an athlete to watch a fast-moving ball make contact with the bat, racket, or glove, etc.
Would McGuire be as good a batter if he hit fewer baseballs and spent more time doing various types of visual training in an eye care professional's office? While many visual abilities are trainable, the transfer to real-world tasks that are related to sports has not been demonstrated.736 The essential factors needed to hit a baseball (and other sports balls) well are: innate ability, excellent visual and motor memory, total body timing, quick visual learning, concentration, and dynamic visual acuity. Important factors include, distance stereopsis, contrast sensitivity, peripheral awareness, and visualization. Not important are accommodation and vergence amplitude and speed.
A batter has to be a quick visual learner. He sees the pitched ball for less than 0.5 seconds per pitch. He has about 7 pitches per each at bat and 4 at bats per game. Each game, the batter has 14 seconds of learning about a particular pitcher. The batter learns the most from the last third of each pitch as he correlates how the final path of the ball relates to the delivery and release of the pitcher. Learning is a total system approach. To be effective in hitting the ball, the batter must see the pitcher's total motion, including the release of the ball. Then he must correlate the biomechanics of his own swing and his visual-motor memory, with the pitcher's delivery and release and the trajectory of the ball.
To help the athlete perform better, vision therapy research and practice should:
|LEGAL IMPLICATIONS OF SPORTS-RELATED EYE INJURIES|
|Prescribing and/or dispensing eyewear for athletes is fertile ground for
litigation because there is significant potential for injury and the
sale of a product is frequently involved. Legal claims can be directed
on the grounds of negligence as well as those of product liability. Negligence
awards for the plaintiff have arisen from failure to prescribe
the lens material of choice and failure to warn of the differences
in impact resistance between various lens materials. Manufacturers of
sunglasses and protective eyewear have had product liability judgments
against them for defects in design that resulted in an otherwise preventable
injury.751,752 It would be legally imprudent for anyone writing a prescription or dispensing
eyewear to athletes not to prescribe polycarbonate753 or Trivex lenses or not to be certain that prescribed sports eyewear meets
applicable safety standards.156 The dispenser should beware of the stylish sunglass with the CR39 or glass
lens that could shatter if struck with a tennis ball, Frisbee, or
softball. It is apparent that malpractice negligence and product liability
suits will remain a significant factor in sports-related
eye injuries and that there are both good and bad aspects to the present
The negative aspects—extravagant awards, capricious juries and judges, inconsistency in awards for apparently similar injuries in apparently similar circumstances, long delay in trials so that physicians and manufacturers are often held to a state of the art that has advanced since the time of the injury, escalating insurance premiums, a long “tail” on protective equipment that has become obsolete yet is still used by the athlete, lawyers' greed and tendency to instigate suit for high awards—are well known to physicians and manufacturers and must be corrected by the legal profession. Product liability suits concerning football helmets resulted in cancellation of the NOCSAE insurance, which would not be replaced by another insurer. This resulted in a withdrawal from NOCSAE of important organizations such as the NCAA, National Federation of State High School Associations, the National Junior College Athletic Association, and the National Athletic Trainers Association, because members of these organizations on the NOCSAE board withdrew to protect themselves from liability.754 It seems counterproductive to the welfare of athletes that a standards setting organization that has done a great deal for sports safety can be radically changed by uninsurability. Rising insurance costs and huge liability awards are threatening some sports and recreation programs.755
The present legal climate—as much as it desperately needs improvement—does however have a significant positive attribute: it is the most efficient check on the small fraction of manufacturers, retailers, and health care professionals who are incompetent or are without conscience and motivated solely by greed. The fact is that the potential of the injured athlete to obtain large awards from the courts has forced manufacturers to gather together to write voluntary consensus standards to upgrade protective devices and help keep inferior products off the market. Administrators are studying risk management, with resultant safer facilities.756 Although suits against eye care professionals for improperly prescribing optical devices are uncommon,757,758 they certainly will increase in frequency as lawyers become aware of advances in eyewear protection that the professional should advise for athletic patients exposed to specific risks. Another area of significant liability risk appears to be failure to warn radial keratotomy, penetrating keratoplasy, and other patients with increased risk of ruptured globe of the extra need for eye protection against traumatic rupture of the globe likely to occur from the energy used in many sports. The optician, dispensing optometrist, and ophthalmologist should take a sports, industrial, and hobby history and advise the use of appropriate protective eyewear. Manufacturers must participate in the voluntary standard-setting process and test their products before release to the general public. Sports officials must be certain that athletes under their supervision are properly protected. Devices that are advertised as protective then fail to give adequate protection will result in litigation.
The responsibilities of teachers and coaches of motor skill activities as well as the agencies that sponsor them were further defined in a $6.3 million award to an injured Seattle high school football player.759 Although this case involved football, the legal principles would probably apply to all supervised sports. The student must be instructed in appropriate skills, be warned of potential dangers, and have available the latest safety precautions and techniques. The participants in sports are also not immune from litigation if they act with more aggression than permitted by the rules of the sport or use the sport as an excuse for acts of violence. Athletic administrators, coaches. doctors, and equipment manufacturers realize that injuries cannot be entirely eliminated from sports, but they must strive to at least minimize the risk of serious injury.760 The best defense in a legal suit seems to be the ability to demonstrate that all concerned were acting responsibly, using state-of-the-art protective devices and playing surfaces, and using conditioning and training techniques to protect the athlete to an acceptable level of risk considering the nature of the sport.144,761
|All who are in position of authority have a responsibility to act in a
positive manner for the benefit and welfare of those under that authority. This
responsibility is fuller and stronger when the responsible person
is dealing with those who are in a position of diminished ability
to be responsible for themselves.424 Therefore, the athletic director or coach of a grammar school team is
more responsible to ensure the safety of his or her charges than is the
professional coach who is dealing with adults who can make an informed
consent. A sport official is ethically responsible for the safety of
the players especially in the school setting, in which the school official
is acting in a parental role, supervising a minor who is under
his or her care during the time of sports participation. To ignore a situation
in which there is a preventable cause of injury and force participants
to play without the benefit of a device that would greatly reduce
the probability of injury is clearly unethical and irresponsible.762|
It is vital to realize that to be beneficial to a child a sport must be fun. Children should have the right to: participate regardless of skill, ability or gender; decide whether they want to participate in sports at all; know that a failure in sports is not a failure in life; have a competent coach; safe facilities, and properly maintained equipment; have their fair share of public funds and facilities; be treated like children, not like miniature adults; competent medical treatment; stop playing when hurt or sick without fear of reprisals; their own individuality; have compassionate organized sports programs; play opponents who are carefully matched in age, weight and size; have a wide variety of sports from which to choose.763
In colleges, football, hockey, and basketball are the income producers that support other sports programs.764 There must be constant vigilance that college players are not viewed as income-producing assets with more attention paid to performance at the expense of safety. The college or professional coach must realize that persons should not have to go along with stupid things and that, while the informed adult may opt to take a risk for himself or herself, he or she should not put other persons at risk. College and professional team physicians must be extremely careful of the dilemma of divided loyalties—to the team that pays the physician's salary and expects winning performance from the athlete as opposed to the athlete who is, in fact, the patient. It is essential that the team physician avoid ambiguity at all costs. If the relationship differs from the customary physician-patient relationship, it is crucial to tell the patient.762,765–768
|ROLE OF EYE-CARE AND ATHLETIC PROFESSIONALS IN EYE INJURY PREVENTION|
|In preventing and treating athletic eye injuries, the well-being
of the athlete must be placed above all other considerations. Ophthalmology, optometry, and
optician organizations should emphasize prevention
as an important part of eye care practice. The ophthalmologist or
optometrist can help the athlete protect his or her eyes by knowing what
to advise, discussing the advise with the athlete, and writing a specific
sports-eyewear prescription. A section of every optical
dispensary should be a display of sports and industrial eyewear that meets
applicable standards, as well as handouts that give specific advice
on eye protection for various activities.|
The school committee members should be sensitive to their responsibility to educate their interscholastic coaches properly and provide athletic trainers. The athletic trainer is the bridge between the medical staff and the athletes and is invaluable in monitoring the athletes for fitness to participate and ensuring that protective equipment complies with applicable safety standards, fits properly, and is properly maintained. Because it is only the coach who is with the athlete before, during, and after both practices and games, the coach assumes the role of everyman. In addition to producing winning teams and teaching proper playing techniques, the coach is expected to keep the athletes healthy and injury free. Because certified athletic trainers and physicians are not present at every game, the coach should have a basic knowledge of injury prevention, recognition, and first aid.
30. Gallagher SS, Finison K, Guyer B, et al: The incidence of injuries among 87,000 Massachusetts children and adolescents: results of the 1980–81 Statewide Childhood Injury Prevention Program Surveillance System. Am J Public Health 74:1340, 1984
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