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Direct Catastrophic Injury in
Sports
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.
I
n 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.
1
Information 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.
JAmAcadOrthopSurg2005;13:445-
454
Copyright 2005 by the American
Academy of Orthopaedic Surgeons.

Volume 13, Number 7, November 2005 445
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.
2
The
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.
2

Football
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.
2
Cheerleading 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.
2
Head 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.
3
Most of the fatalities

were associated with subdural he-
matomas (86%) and occurred in high
school athletes (75%) during game
situations (61%).
3
The 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.
4
New data re-
veal that the great majority of inju-
ries occurred to the player being
tackled.

4
Often 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 al
5
were
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 dramatically,
from 34 in 1976 to 3 in 1992
6,7
(Fig-
ure 3).
Cervical cord neurapraxia (CCN)
is an acute, transient neurologic ep-
isode associated with sensory chang-
es with or without motor weakness
Table 1
Sources of Information on Sport Safety
American Association of Cheerleading Coaches and Advisors (AACCA) www.aacca.org
U.S. Consumer Product Safety Commission (CPSC) www.cpsc.gov
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
Pole Vault Safety Certification Board (PVSCB) www.pvscb.com
USA Baseball www.usabaseball.com
Direct Catastrophic Injury in Sports
446 Journal of the American Academy of Orthopaedic Surgeons
or complete paralysis in at least two
extremities.
8,9

The estimated preva-
lence among football players is 7 per
10,000.
6
Complete 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.
9
The

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.)
Barry P. Boden, MD
Volume 13, Number 7, November 2005 447
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.
6

The 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.
10
Many foot-
ball players have large vertebral bod-
ies with normal canal dimensions,
which may bring the ratio below
0.8.
11
Therefore, 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.)
Direct Catastrophic Injury in Sports
448 Journal of the American Academy of Orthopaedic Surgeons
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.
14
The NCCSIR reports
approximately two direct cata-
strophic cheerleading injuries per
year (0.6 per 100,000 cheerlead-
ers).
14
In 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.

14
In 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.)
Barry P. Boden, MD
Volume 13, Number 7, November 2005 449
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 in-
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.
15
Baseball 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.
17
In 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 hardness and weight may
significantly reduce injury severity
to players hit by a batted ball.
20
The
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.
22,23
The
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.
Direct Catastrophic Injury in Sports
450 Journal of the American Academy of Orthopaedic Surgeons
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.
26
The 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 al
28
reported 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.
29
Most 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.
30
Head 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.
31
Eye 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.
31
Aggressive play
and fighting also should be discour-
aged and penalized appropriately. The
“heads up, don’t duck” program
teaches players to avoid contact with
Barry P. Boden, MD

Volume 13, Number 7, November 2005 451
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.
2
The
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. During 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.
Direct Catastrophic Injury in Sports
452 Journal of the American Academy of Orthopaedic Surgeons
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.
34
It 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.
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