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The NCCSIR defines catastrophic sports injury as “any severe spinal, spinal cord, or cerebral injury incurred dur-ing participation in a school/college sponsored sport.”1 Injuries are cl

Abstract

Catastrophic sports injuries are rare but tragic events Direct (traumatic) catastrophic injury results from participating in the skills of a sport, such as a collision in football Football is associated with the greatest number of direct catastrophic injuries for all major team sports in the United States Pole vaulting, gymnastics, ice hockey, and football have the highest incidence of direct catastrophic injuries for sports in which males participate In most sports, the rate of catastrophic injury is higher at the

collegiate than at the high school level Cheerleading is associated with the highest number of direct catastrophic injuries for all sports in which females participate Indirect (nontraumatic) injury

is caused by systemic failure as a result of exertion while participating in a sport Cardiovascular conditions, heat illness, exertional hyponatremia, and dehydration can cause indirect catastrophic injury Understanding the common mechanisms of injury and prevention strategies for direct catastrophic injuries is critical in caring for athletes

In the United States,

approximate-ly 10% of all brain injuries and 7%

of all new cases of paraplegia and quadriplegia are related to athletic activity.1Information on

catastroph-ic injuries in athletes is collected by the National Center for

Catastroph-ic Sports Injury Research (NCCSIR), the United States Consumer Prod-uct Safety Commission (CPSC), and other organizations (Table 1) The NCCSIR defines catastrophic sports injury as “any severe spinal, spinal cord, or cerebral injury incurred dur-ing participation in a school/college sponsored sport.”1

Injuries are classified by the NCCSIR as direct, resulting from participating in the skills of a sport (ie, trauma from a collision), or indi-rect, resulting from systemic failure caused by exertion while

participat-ing in a sport Direct and indirect in-juries are subdivided into three cat-egories: serious, nonfatal, and fatal

A serious injury is a severe injury with no permanent functional dis-ability (eg, a fractured cervical verte-bra without paralysis).1 A nonfatal injury is any injury in which the ath-lete suffers a permanent, severe, functional disability Indirect deaths

in athletes are predominantly caused

by cardiovascular conditions, such

as hypertrophic cardiomyopathy and coronary artery disease Concus-sions are not considered

catastroph-ic injuries by the NCCSIR However, their frequency and potential for long-term sequelae warrant discus-sion

The CPSC operates a statistically valid injury and review system known as the National Electronic

In-Barry P Boden, MD

Dr Boden is Adjunct Associate

Professor of Surgery, Uniformed

Services, University of the Health

Sciences, Bethesda, MD, and

Orthopaedic Surgeon, The Orthopaedic

Center, Rockville, MD.

Neither Dr Boden nor the department

with which he is affiliated has received

anything of value from or owns stock in a

commercial company or institution

related directly or indirectly to the

subject of this article.

Reprint requests: Dr Boden, The

Orthopaedic Center, 9711 Medical

Center Drive, #201, Rockville, MD

20850.

J Am Acad Orthop Surg

2005;13:445-454

Copyright 2005 by the American

Academy of Orthopaedic Surgeons.

jury Surveillance System Their

esti-mates are calculated using data from

a sample of hospitals that are

repre-sentative of emergency departments

in the United States The CPSC does

not provide data on injury specifics,

nor does it include information on

injuries that are initially presented to

physicians The National Collegiate

Athletic Association (NCAA) and the

National Federation of State High

School Associations (NFSH) review

injury epidemiology annually and

publish a rules book for each sport

with the intent of promoting safe

play

Epidemiology

For all sports followed by the

NCCSIR, the total incidence of direct

and indirect catastrophic injuries is

1 per 100,000 high school athletes and

4 per 100,000 college athletes.2The

combined fatality rate for direct and

indirect injuries is 0.40 per 100,000

high school athletes and 1.42 per

100,000 collegiate athletes.2Football

is associated with the greatest

num-ber of direct catastrophic injuries for

all major team sports Football, pole

vaulting, gymnastics, and ice hockey

have the highest incidence of direct

catastrophic injuries per 100,000 male

participants.2Cheerleading is

associ-ated with the highest number of

di-rect catastrophic injuries for all sports

in which females participate.2

Direct Injury Football

Head Injury

Football is associated with the highest number of severe head and neck injuries per year for all high school and college sports.2Head in-juries are the most common direct cause of death among football play-ers, accounting for 69% of all foot-ball fatalities (497/714) from 1945 through 1999.3Most of the fatalities were associated with subdural he-matomas (86%) and occurred in high school athletes (75%) during game situations (61%).3The greatest num-ber of brain injury–related fatalities occurred from 1965 through 1969

There has been a dramatic decrease

in brain injury–related fatalities over the subsequent three decades A ma-jor factor in the decline of head inju-ries since the 1960s is improved hel-met design and the establishment of safety standards by the National Op-erating Committee on Standards for Athletic Equipment Improved med-ical care and technology also likely are responsible for the decline in fa-talities

Nonfatal head injuries are ex-tremely common in football; nearly

900 concussions were reported in the National Football League be-tween 1996 and 2001.4New data re-veal that the great majority of

inju-ries occurred to the player being tackled.4Often the concussed player was hit from the side on the lower half of the face by the crown of an opponent’s helmet New football helmets with better padding around the ear and jaw are currently being tested (Figure 1)

Cervical Injury

Although the incidence of head injury−related fatalities began to de-cline in the early 1970s, the number

of cases of permanent cervical quad-riplegia continued to rise This change likely is because of the im-proved helmets, which allowed tack-lers to strike an opponent using the crown of the head with less fear of self-induced injury Torg et al5were instrumental in reducing the rate of quadriplegic events by demonstrating that spear-tackling a player with the top of the head is the major cause of permanent cervical quadriplegia (Fig-ure 2) When the neck is flexed 30°, the cervical spine becomes straight and the force of the impact is trans-mitted directly to the spinal struc-tures After spearing was banned in

1976, the rate of catastrophic cervi-cal injuries declined dramaticervi-cally, from 34 in 1976 to 3 in 19926,7 (Fig-ure 3)

Cervical cord neurapraxia (CCN)

is an acute, transient neurologic ep-isode associated with sensory

chang-es with or without motor weaknchang-ess

Table 1

Sources of Information on Sport Safety

American Association of Cheerleading Coaches and Advisors (AACCA) www.aacca.org

The National Collegiate Athletic Association (NCAA) www.ncaa.org National Center for Catastrophic Sport Injury

Research (NCCSIR)

www.unc.edu/depts/nccsi/ National Center for Injury Prevention and Control (NCIPC) www.cdc.gov/ncipc/ Centers for Disease Control and Prevention (CDC) www.cdc.gov/ National Federation of State High School Associations (NFHS) www.nfhs.org National Operating Committee on Standards for Athletic Equipment (NOCSAE) www.nocsae.org

or complete paralysis in at least two

extremities.8,9The estimated

preva-lence among football players is 7 per

10,000.6Complete recovery usually

occurs within 10 to 15 minutes but

may take longer Cervical stenosis is

believed to be the primary causative

factor predisposing to CCN The

hy-pothesized mechanism of injury is

either hyperflexion or

hyperexten-sion of the neck causing a

pincer-type compression injury to the

spi-nal cord

An episode of CCN is not an

ab-solute contraindication to return to

football Although published

num-bers are too low to make any

defin-itive statement, it is unlikely that an

athlete who experiences CCN is at

risk for permanent neurologic

se-quelae with return to play The

over-all risk of a recurrent CCN episode

with return to football is slightly

more than 50% and is correlated

with the canal diameter size The

smaller the canal diameter, the

greater the risk of recurrence.9The

athlete with ligamentous instability;

neurologic symptoms lasting more

than 36 hours; multiple episodes; or

evidence of cord defect, cord edema,

or minimal functional reserve on

magnetic resonance imaging should

not be allowed to return to contact

sports.6

Figure 2

Football player spear-tackling an opponent using the top of the head (Reprinted with permission from Torg JS, Guille JT, Jaffe S: Injuries to the cervical spine in

American football players J Bone Joint Surg Am 2002;84:112-122.)

Figure 3

The decline in cervical quadriplegic events after spear-tackling was banned in 1976 (Reprinted with permission from Torg JS, Guille JT, Jaffe S: Injuries to the cervical

spine in American football players J Bone Joint Surg Am 2002;84:112-122.)

Figure 1

New football helmet design that

provides more protection to the side of

the face (Reprinted courtesy of

Riddell, Inc, Chicago, IL.)

The Torg-Pavlov ratio, which was

developed as a method to assess

cer-vical spinal stenosis, eliminates the

need to correct for radiographic

mag-nification.6The ratio is calculated by

dividing the diameter of the spinal

canal by the anteroposterior width of

the vertebral body at the midpoint on

the lateral radiograph A ratio <0.8

was proposed as indicating

signifi-cant spinal stenosis The ratio has a

high sensitivity for detecting

signif-icant spinal stenosis but a poor

pos-itive predictive value In one study,

40 (32%) of 124 professional football

players had a ratio <0.8.10Many

foot-ball players have large vertebral

bod-ies with normal canal dimensions,

which may bring the ratio below

0.8.11Therefore, the ratio is a poor

screening tool for athletic

participa-tion Functional spinal stenosis,

de-fined as loss of cerebrospinal fluid

around the spinal cord (documented

by magnetic resonance imaging or computed tomography myelogra-phy), is a more accurate method of determining spinal stenosis.12 There is currently no cost-effective tool to screen for athletes at risk for CCN; however, all athletes who experience an episode of CCN should undergo appropriate imaging studies to evaluate the risk of recur-rence During the preparticipation physical examination, the physician should specifically ask whether an athlete has had a previous head or neck injury in order to provide ap-propriate counseling and return-to-play decisions

Pole Vaulting

Pole vaulting is a unique sport in that athletes often land from heights ranging from 10 to 20 feet Pole vaulting has one of the highest rates

of direct, catastrophic injuries per

100,000 participants for all sports monitored by the NCCSIR.13 The great majority of catastrophic pole vaulting injuries are head injuries occurring in male high school ath-letes.13 The overall rate of cata-strophic pole vault injuries is ap-proximately 2.0 per year, with 1.0 fatality per year.13 This is a high number, considering that there are only approximately 25,000 to 50,000 high school pole vaulters each year Three common mechanisms of injury have been described.13 The most typical occurs when the vault-er’s body lands on the edge of the landing pad and the head whips off the pad, striking a surrounding hard surface, such as concrete or asphalt The second most common scenario occurs when the vaulter releases the pole prematurely or does not have enough momentum and lands in the vault or planting box The third most common mechanism occurs when the vaulter completely misses the pad and lands directly on the sur-rounding hard surface

In response to the high cata-strophic injury rate, both the NCAA and National Federation of State High School Associations (NFHS) decided to increase the minimum pole vault landing pad size from 16'

× 12' to 19'8″× 16'5″as of January

2003 (Figure 4) Because most inju-ries are caused by the athlete’s com-pletely or partially missing the land-ing pad, this rule change could significantly reduce the number of catastrophic injuries The rules com-mittee also proposed enforcing a rule established in 1995 that any hard or unyielding surface (eg, concrete, metal, wood, asphalt) around the landing pad must be padded or cush-ioned A new rule has been adopted placing the crossbar farther back over the landing pad to reduce the chance of an athlete’s landing in the vault or planting box A painted square in the middle of the landing pad (coaching box) is also being pro-moted and should help train athletes

to instinctively land near the center

Figure 4

Footprint of high school landing pad after rule change requiring larger landing pad

Illustration also demonstrates recommended coaching box (Adapted with

permission from Boden BP, Mueller FO: Catastrophic injuries in pole-vaulters

Sports Medicine Update Jan-Feb 2003:4-7.)

of the landing pad (The athlete’s

head and shoulders should land

in-side the painted box Thus, the box

allows the pole vaulter and coach to

adjust performance variables for

effi-ciency and safety.) Other safety

mea-sures include marking the runway

distances so athletes can better

gauge their takeoff and prohibiting

the practice of tapping or assisting

the vaulter at takeoff Pole vaulting

is a complicated sport that requires

extensive training and

knowledge-able coaching; therefore,

certifica-tion of coaches is encouraged The

value of helmets in reducing head

in-juries in high school pole vaulters is

controversial Without conclusive

data regarding their protective effect,

the use of helmets is optional at this

time

Cheerleading

Over the past 20 years,

cheerlead-ing has evolved into an activity

de-manding high levels of skill,

athlet-icism, and complex gymnastic

maneuvers In 2002, cheerleading

was one of the most popular

orga-nized sports activities for girls in

high school Compared with other

sports, cheerleading has a low

over-all incidence of injury, but there is a

high risk of catastrophic injury At

the college and high school levels,

cheerleading injuries account for

more than half of the catastrophic

injuries occurring in female

ath-letes.2 College athletes are more

likely to sustain a catastrophic

inju-ry than their high school

counter-parts, probably because of the

in-creased complexity of stunts at the

college level.14The NCCSIR reports

approximately two direct

cata-strophic cheerleading injuries per

year (0.6 per 100,000

cheerlead-ers).14In 2000, the CPSC estimated

that there were 1,258 head injuries

and 1,814 neck injuries in

cheerlead-ers of all ages; 6 were skull fractures

and 76, cervical fractures

The most common stunts

result-ing in catastrophic injury are the

basket toss and the pyramid; the

cheerleader at the top of the pyramid

is most frequently injured.14In the basket toss, the cheerleader is thrown into the air, often between 6 and 20 feet, by three or four tossers (Figure 5) Less common mecha-nisms include advanced floor tum-bling routines, performing on a wet surface, or performing a mount

Most injuries occur when an athlete lands on a hard indoor gym sur-face.14

The NFHS and NCAA have at-tempted to reduce pyramid injuries

by limiting the height and complex-ity of a pyramid and by specifying positions for spotters (The spotter is the individual who remains on the ground to assist and catch the top person in the pyramid.) Height re-strictions on pyramids are limited to two levels in high school and to 2.5 body lengths in college The top cheerleaders are required to be sup-ported by one or more individuals (base) who are in direct weight-bearing contact with the performing surface Spotters must be present for each person extended above shoul-der level The suspended person is not allowed to be inverted (head be-low horizontal) or to rotate on the dismount Limiting the number of cheerleaders in a pyramid and taking care during the quick transition be-tween pyramids and other complex stunts also may help reduce injuries

Safety measures have been insti-tuted for the basket toss as well, such as limiting the basket toss to four throwers, starting the toss from the ground level (no flips), and hav-ing one of the throwers positioned behind the top person (flyer) during the toss The flyer is trained to main-tain a vertical position and to not al-low the head to drop backward out

of alignment with the torso or below

a horizontal plane with the body

Other preventive measures that may reduce the incidence of basket toss injuries include evaluating the height thrown, using mandatory landing mats for complex stunts, and improving the skills of the

spot-ters Several injuries have been re-ported during rainy weather; thus, all stunts should be restricted in the presence of wet conditions Injury during floor tumbling routines can

be prevented by proper supervision,

by progression to complex tumbling only when simple maneuvers are mastered, and by using spotters as necessary Mini trampolines, spring-boards, or any other apparatus used

to propel a participant have been prohibited since the late 1980s During practice, cheerleading coaches need to devote as much time and attention on the technique

Figure 5

Basket toss in cheerleading (Adapted with permission from Boden BP, Tacchetti R, Mueller FO: Catastrophic

cheerleading injuries Am J Sports Med

2003;31:881-888.)

and attentiveness of the spotters as

on the athletes performing the

stunts Coaches are encouraged to

complete a safety certification,

espe-cially for any teams that perform

pyramids, basket tosses, and/or

tum-bling Pyramids and basket tosses

should be limited to experienced

cheerleaders who have mastered all

other skills They should not be

per-formed without qualified spotters or

landing mats

Baseball

Similar to cheerleading, baseball

has a low rate of noncatastrophic

juries, but it has a relatively high

in-cidence of catastrophic injuries

Head injuries constitute the

majori-ty of catastrophic injuries

Approxi-mately two direct catastrophic

inju-ries are reported to the NCCSIR

each year (0.5 injuries per 100,000

participants).2,15

The most common mechanism of

catastrophic injury in baseball is a

collision, either between fielders or

between a base runner and a fielder.15

Proper training is the easiest way to

prevent collisions between fielders

When an outfielder and infielder are

racing for a ball, the outfielder

should call off the infielder When

two infielders are running for a

pop-up, the pitcher should determine

who catches the ball Players should

be drilled on these techniques in

practice sessions so that they

be-come instinctual in game situations

Collisions between base runners

and fielders often involve the

catch-er A typical scenario is a base

run-ner who dives headfirst into a

catch-er and sustains an axial compression

cervical injury.15Baseball rules state

that the runner should avoid the

fielder because the latter has the

right to the base path

Unfortunate-ly, this rule is not always enforced

when a base runner is racing toward

home plate Because the speed of

headfirst sliding has been shown not

to be statistically different from

feet-first sliding, the rule allowing

head-first sliding should be reassessed at

the high school and college levels.16

In Little League baseball, headfirst sliding is not allowed at any base

The next most common injury mechanism after collisions is a pitcher hit by a batted ball The pitcher is vulnerable to injury be-cause of the proximity to the batter and from being propelled forward, of-ten off balance, toward the batted ball Many coaches and concerned parents perceive a problem from non-wood (eg, aluminum) bats and have demanded that regulations be placed on non-wood bats Their lighter weight allows aluminum bats to be swung faster than wood bats, resulting in a higher ball exit velocity.17In response to the poten-tial problem, the NCAA and NFHS now require all high school and col-lege bats to be labeled with a perma-nent certification mark indicating that the ball exit speed ratio cannot exceed 97 miles per hour, as set by the Baum Hitting Machine (Baum-Bat, Traverse City, MI) Other impor-tant new regulations relate to bat thickness and weight: the thickest diameter of the bat (barrel diameter)

is restricted to 2.625 in, and the weight of the bat in ounces shall not

be less than the length of the bat in inches minus three (ie, a 34-in–long bat cannot weigh less than 31 oz).18,19 Although these regulations show promise for reducing the num-ber of injuries, no clinical studies to date confirm their effectiveness

In addition to regulating the bat, several other measures are available

to protect pitchers Protective screens (L-screens) are

recommend-ed at all times during practice ses-sions Unfortunately, screens are not practical during game situations

Players and coaches also should be educated about the risk to pitchers, who should have the option of wear-ing protective equipment Finally, it has been hypothesized that

decreas-es in ball hardndecreas-ess and weight may significantly reduce injury severity

to players hit by a batted ball.20The coefficient of restitution, which is

the measure of rebound that a ball has off a hard surface, has been adopted as the testing standard for baseballs At the high school and collegiate levels, the coefficient of restitution of a baseball cannot ex-ceed 0.555

Another concern in baseball is commotio cordis or arrhythmia, which is often associated with sud-den death from low-impact blunt trauma to the chest in subjects with

no preexisting cardiac disease.21 These incidents occur most com-monly in baseball, but they have been reported to occur in hockey, softball, lacrosse, and other sports The proposed mechanism of injury

is impact just before the peak of the

T wave, which induces ventricular fibrillation Although the rate of res-cue from commotio cordis was ini-tially documented to be extremely low, more recent reports indicate that survival is possible with imme-diate resuscitative measures, such as

a precordial thump or use of an auto-matic external defibrillator.22,23The pediatric population may be more susceptible to commotio cordis be-cause of the thinner layer of soft tis-sue to the chest wall, increased com-pliance of the immature rib cage, and slower protective reflexes Preventive measures for commo-tio cordis have focused on chest pro-tectors and soft-core baseballs.24,25 Unfortunately, neither has been shown to reduce the risk of arrhyth-mia and may in fact exacerbate the force to the chest Preventive strate-gies are currently limited to teaching youth baseball players to turn the chest away from a wild pitch, a bat-ted ball, or a thrown ball Further analysis is required of the biome-chanics of commotio cordis and the effectiveness of resuscitative mea-sures, especially with automatic ex-ternal defibrillators

Soccer

Injuries to the head, neck, and face account for between 5% and 15% of all injuries in soccer players

Most head and neck injuries occur

when two players collide, especially

when jumping to head the ball

Fa-talities are usually associated with

either a movable goalpost falling

onto a player or player impact with

the goalpost.26The CPSC identified

at least 21 deaths associated with

movable goalposts over a 16-year

pe-riod Goalpost injuries can be

pre-vented by never allowing children to

climb on the net or the goal

frame-work Soccer goalposts should be

se-cured at all times During the

off-season, goals should be either

disassembled or placed in a safe

stor-age area Goals should be moved

only by trained personnel and should

be used only on flat fields The use of

padded goalposts also may reduce

the incidence of impact injuries with

the posts.26

Although catastrophic head

inju-ries are rare in soccer, the incidence

of concussions is relatively high at

the elite college level, with

approxi-mately one per team per season.27

Barnes et al28reported that male

pro-fessional soccer players have a 50%

risk of sustaining a concussion over

a 10-year span Most concussions

oc-cur as a result of contact with an

op-posing player—especially

head-to-head collisions—rather than with

the soccer ball.27 No evidence

sug-gests that an isolated episode of

heading a soccer ball causes head

in-jury; however, there is controversy

as to whether repetitive heading

over a prolonged soccer career can

lead to neuropsychological deficits

Until conclusive data show that

repetitive heading of a soccer ball

causes no long-term damage, it is

recommended that children use

smaller soccer balls to reduce head

impact Leather or water-soaked

soc-cer balls should never be used

be-cause of their heavier weight

Prop-er heading techniques also should be

taught: contact should be made with

the forehead, with the neck muscles

contracted Soccer players should be

trained to hit the ball, not to be hit

by the ball A long-term prospective

study on the cumulative effects of heading a soccer ball is underway

Wrestling

Approximately two direct cata-strophic wrestling injuries occur per year at the high school and college levels (1 per 100,000 participants).29 There is a trend toward more direct injuries in the lightweight and mid-dleweight classes The majority of direct catastrophic wrestling injuries are cervical fractures or major cervi-cal ligament injuries.29Most injuries occur in match competitions, in which intense, competitive situa-tions place wrestlers at higher risk.29

The position most frequently as-sociated with injury is the defensive posture during the takedown ma-neuver, followed by the down position (kneeling), and the lying position.29 There is no clear pre-dominance of any one type of take-down hold that contributes to wrestling injuries The athlete is typically injured by one of three sce-narios (1) The wrestler’s arms are in

a hold such that he or she is unable

to prevent himself or herself from landing on his or her head when thrown to the mat (2) The wrestler attempts a roll but is landed on by the full weight of the opponent, causing a twisting (usually hyper-flexion) neck injury (3) The wrestler lands on the top of his or her head, sustaining an axial compression force to the cervical spine

Referees and coaches are

critical-ly important in preventing direct catastrophic wrestling injuries Ref-erees should strictly enforce penal-ties for slams and should gain more awareness of dangerous holds.29 Stringent penalties for intentional slams or throws are encouraged The referee should have a low threshold

of tolerance for stopping the match during potentially dangerous situa-tions Coaches can prevent serious injury by emphasizing safe, legal wrestling techniques, such as teach-ing wrestlers to keep the head up

during any takedown maneuver to prevent axial compression injury to the cervical spine.29 Proper rolling techniques, which include avoiding landing on the head, need to be em-phasized in practice sessions

Ice Hockey

Although the number of cata-strophic injuries in ice hockey is low compared with other sports, the in-cidence per 100,000 participants is high.2 Catastrophic accidents from collisions with goal cages were com-mon before the advent of displace-able goal cages Most recent cata-strophic injuries have been reported

to occur in the cervical spine, espe-cially between levels C5 and C7.30 The most common mechanism of injury is checking from behind and being hurled horizontally into the boards (Figure 6) Contact with the boards typically occurs to the crown

of the player’s head, subjecting the neck to an axial load.30Head and fa-cial injuries, which are caused by collisions, fighting, and being hit by the puck or stick, also are common The frequency and severity of head and neck injuries may be re-duced by enforcing current rules against pushing or checking from be-hind, padding the boards, and encour-aging the use of helmets and face masks In a prospective analysis of fa-cial protection in elite amateur ice hockey players, players wearing no protection were injured twice as of-ten as players wearing partial protec-tion, and nearly seven times more of-ten than those wearing full protection.31Eye injuries were nearly five times greater for players with no facial protection compared with those wearing partial protection Al-though it has been suggested that wearing head and facial protection leads to an increased risk of cata-strophic spinal injury, this has not been substantiated.31Aggressive play and fighting also should be discour-aged and penalized appropriately The

“heads up, don’t duck” program teaches players to avoid contact with

the top of the head when taking a check, giving a check, or sliding on the ice In the Safety Toward Other Players (STOP) program, a STOP patch is affixed to the back of the jer-sey of amateur athletes as a visual re-minder not to hit an opponent from behind

Swimming

Most catastrophic swimming in-juries are related to the racing dive into the shallow end of the pool.2The NFHS and NCAA have implemented rules to prevent injury during the rac-ing dive At the high school level, swimmers must start the race in the water when the depth at the starting end of the pool is <3.5 ft When the water depth is 3.5 ft to <4 ft at the starting end, the swimmer may start

in the water or from the deck When the water depth at the starting end is

≥4 ft, the swimmer may start from a platform up to 30 in above the water surface The NCAA requires a min-imum water depth of 4 ft at the start-ing end of the pool Durstart-ing practice sessions in which platforms may not

be available, swimmers are advised

to dive into only the deep end of the

Figure 6

A and B, An ice hockey player (no 8) sustaining an axial cervical injury against the boards (Courtesy of J S Torg, MD,

Philadelphia, PA.)

Table 2

Guidelines on Exercise Restriction for Athletes With Cardiovascular

Disease

Contraindications to vigorous exercise

Hypertrophic cardiomyopathy

Idiopathic concentric left ventricular hypertrophy

Marfan syndrome

Coronary heart disease

Uncontrolled ventricular arrhythmia

Severe valvular heart disease (especially aortic stenosis and pulmonic

stenosis)

Coarctation of the aorta

Acute myocarditis

Dilated cardiomyopathy

Congestive heart failure

Congenital anomaly of the coronary arteries

Cyanotic congenital heart disease

Pulmonary hypertension

Right ventricular cardiomyopathy

Ebstein’s anomaly of the tricuspid valve

Idiopathic long QT syndrome

Conditions requiring close monitoring and possible restriction

Uncontrolled hypertension

Uncontrolled atrial arrhythmia

Hemodynamic significant valvular heart disease (eg, aortic insufficiency,

mitral stenosis, mitral regurgitation)

Adapted with permission from 26th Bethesda Conference: Recommendations for

determining eligibility for competition in athletes with cardiovascular abnormalities.

January 6-7, 1994 J Am Coll Cardiol 1994;24:845-899.

pool or to jump into the water feet

first

Indirect Injury

Indirect (nontraumatic) catastrophic

injury and death in athletes are

pre-dominantly caused by

cardiovascu-lar conditions, such as hypertrophic

cardiomyopathy, coronary artery

anomaly, arrhythmogenic right

ven-tricular dysplasia, myocarditis, and

dysrhythmia.32 Noncardiac

condi-tions that cause catastrophic

indi-rect injuries are heat illness,

dehy-dration, exertional hyponatremia,

rhabdomyolysis, status asthmaticus,

and electrocution caused by

light-ning A complete personal and

fam-ily history as well as a physical

ex-amination are recommended for all

athletes before participating in

sports Participation guidelines for

athletes with cardiovascular

condi-tions are summarized in Table 2.33

At the preparticipation physical, the

physician should specifically ask

whether an athlete has had a

previ-ous head or neck injury in order to

determine appropriate counseling

and make decisions about return to

play

Summary

Physical activity has numerous

health-related benefits Nonetheless,

there is a risk of catastrophic injury

in certain organized sports,

particu-larly football, pole vaulting,

cheer-leading, and ice hockey The cost to

the injured athlete and to society can

be great In addition to the decreased

quality of life for the patient, the

life-time cost of caring for a complete

quadriplegic individual can easily

exceed $2 million.34It has been

esti-mated that the annual aggregate cost

of treating patients with

sports-related spinal cord injury in the

United States in 1995 was close to

$700 million.34 Prevention is the

most effective means of reducing the

incidence and costs associated with

catastrophic head and neck injury in

sports Continued research of the ep-idemiology and mechanisms of cat-astrophic injury is critical to pre-venting these injuries

Acknowledgment

The author wishes to thank Freder-ick Mueller, PhD, for sharing data from the NCCSIR

References

Evidence-based Medicine:Reported are primarily level III, IV, and V pro-spective cohort, retropro-spective cohort, and case controlled studies There have been no level I or II prospective randomized or cohort studies assess-ing the causation or treatment of di-rect catastrophic injury in sports

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