(aspects of sports medicine • an original study)

Incidence and Variance of Foot and Ankle Injuries in Elite College Football Players

Lee D. Kaplan, MD, Patrick W. Jost, MD, Nicholas Honkamp, MD, John Norwig, ATC, Robin West, MD, and James P. Bradley, MD

Abstract injured). The most common inju- studied with respect to many vari- We conducted a study on the risk ries were lateral ankle sprain ables, few studies have evaluated for foot and ankle injuries in col- (n = 115), syndesmotic sprain (50), player position–specific trends lege football players on the basis metatarsophalangeal dislocation/ concerning these injuries. Torg of injury type and player position. turf toe (36), and fibular fracture and Quederfeld14 analyzed knee In February 2006, we evaluated 320 (25). Foot and ankle injuries were and ankle injuries with a focus intercollegiate football players at the most common in kickers/punters National Football League Combine. (100% incidence), special teams on athletic shoes and cleats, and 15 All pathologic conditions and surgi- (100%), running backs (83%), Tyler and colleagues reported cal procedures of the foot and ankle wide receivers (83%), and offen- that players with previous ankle were recorded, and data were ana- sive linemen (80%). Lateral ankle sprains and high body mass indi- lyzed by player position to detect any trends. Seventy-two percent (n = 231) “Various studies have reported of the players had a history of foot and ankle injuries, with that linemen are at highest risk for a total of 287 foot and ankle injuries (1.24 injuries/player knee injury.”

Dr. Kaplan was Assistant Professor sprains, the most common injuries, of Orthopedic Surgery, Department ces were more at risk for sustain- of Orthopedics and Rehabilitation, were treated surgically only 2.6% ing another ankle sprain. In a University of Wisconsin, Madison, of the time. Offensive linemen were study of injury rates by position Wisconsin. He is now Chief, Division most likely to have had syndesmot- of Sports Medicine, and Faculty, Miller over a 14-year period, Brophy ic sprains (32%), and quarterbacks 16 School of Medicine, University of Miami, had the highest incidence of fibular and colleagues found that ankle Miami, Florida. sprains were consistently the Dr. Jost was Medical Student, University fractures (16%). of Wisconsin, Madison, Wisconsin. He Foot and ankle injuries are common most common injuries and that is now Resident, Hospital for Special in collegiate football players, affect- the incidence of ankle sprains Surgery, New York, New York. ing 72% of players. Thirteen percent increased over the study period. Dr. Honkamp was Fellow, Department underwent surgical treatment. Trends of Sports Medicine, University of Various studies have reported that Pittsburgh, Pittsburgh, Pennsylvania. He are seen in the types of injuries for the linemen are at highest risk for is now Member, Des Moines Orthopaedic different player positions. knee injury.5,9,14,15,17,18 Turbeville Surgeons, Des Moines, Iowa. 19 Mr. Norwig is Head Athletic Trainer, n estimated 11% to 81% of and colleagues, in a study of Pittsburgh Steelers, Pittsburgh, participants in American high school players, found line- Pennsylvania. football sustain an injury men to be at highest risk for Dr. West is Assistant Professor of Orthopedic Surgery, and Dr. Bradley is at some time while play- knee injury and season-ending Clinical Associate Professor, Department A 1,2 ing the sport. Numerous studies injury. However, other stud- of Sports Medicine, University of have evaluated the injury rates of ies have found running backs to Pittsburgh, Pittsburgh, Pennsylvania. players in youth football to college have the highest risk for over- Address correspondence to: Patrick W. and professional football.3-8 Foot all injury. Canale and colleagues3 Jost, MD, Hospital for Special Surgery, and ankle injuries, along with knee reported that fullbacks have the 535 E 70th St, New York, NY 10021 (tel, 212-606-7376; fax, 212-606-1477; e-mail, and hand injuries, are consistently highest statistical risk for over- [email protected]). among the most common types of all injury. Evaluating high school musculoskeletal injury.3-13 football players in California, Am J Orthop. 2011;40(1):40-44. Copyright 20 Quadrant HealthCom Inc. 2011. All rights Although foot and ankle injuries Ramirez and colleagues docu- reserved. are quite common and have been mented running backfielders—a

40 The American Journal of Orthopedics® L. D. Kaplan et al

Table I. Incidence of Foot and Ankle Injuries and Surgeries by Player Position

Players Players With Injury Players With Surgery Position (n) n % n %

Running back 29 24 82.8 7 24.1 Wide receiver 40 33 82.5 5 12.5 Offensive lineman 50 40 80.0 7 14.0 Defensive back 59 41 69.5 2 3.4 Defensive lineman 54 37 68.5 6 11.1 Linebacker 36 24 66.7 4 11.1 Tight end 21 13 61.9 4 19.0 Quarterback 25 13 52.0 3 12.0 Kicker/punter 4 4 100.0 1 25.0 Special teams 2 2 100.0 1 50.0 Total 320 231 72.2 40 12.5 category that includes wide receiv- to participate in the 2006 Combine. patterns when necessary. Estimated ers, cornerbacks, defensive backs, All players attended voluntarily loss of playing time and nonop- safeties, running backs, and full- and provided written consent to erative treatment protocols were not backs—as having a higher risk for be evaluated. Each player provided collected. injury when compared with line- a thorough medical history and The association between foot and men. Culpepper and Niemann4 underwent a complete physical ankle injuries (or procedures) and asserted that players who handle examination by NFL team ortho- player position was assessed with the ball are the most likely to be pedic surgeons, with specific detail- c2 tests. Only injuries and diagnoses injured, with quarterbacks having ing on previous injuries, treatment, that had at least 10 observations the highest percentage of injuries and current status. Medical history were considered. When a difference in their study. To our knowledge, was obtained from the records of was found at a significance level of no study has assessed the relation- the player’s college training staff, 5%, the individual cell contribu- ship between a player’s position professional team scouts, and the tion to the c2 statistic was com- and his risk for sustaining a foot player’s own report. The previous puted, and a value exceeding 2.5 or ankle injury. medical and surgical records and was noted as a possible source for We conducted this study to previous and current imaging stud- the significance. All computations determine the incidence of foot ies were analyzed during the medi- and figures were done in R for and ankle injuries in elite col- cal evaluation. Windows (version 2.1.0, patched legiate American football players Drs. Kaplan and Bradley 2005-04-18). and the relationship to player posi- obtained histories of foot and tion. The hypothesis was that foot ankle injuries from each player, Results and ankle injuries in American either directly or from the team. Three hundred twenty elite football players would be related This was followed by a discus- college football players (165 to player position. sion of mechanism of injury with offensive players, 149 defensive the player and a directed physi- players, 6 placekickers and spe- Methods cal examination to independently cialists) were evaluated at the 2006 The University of Wisconsin insti- verify the diagnosis. NFL Combine. Defensive backs tutional review board and the For the purpose of this study, all (n = 59), defensive linemen (54), National Football League (NFL) athletes with a history of foot and offensive linemen (50), and wide Health and Safety Committee ankle injury or surgery were identi- receivers (40) had the largest num- provided approval for this study. fied during the medical evaluation. ber of athletes per position evalu- The study was conducted dur- The information collected included ated and comprised 63% of the ing the 2006 NFL Combine in player position, injury type, and athletes at the Combine (Table I). Indianapolis, Indiana, where elite all surgical procedures performed. A history of a foot and ankle inju- college football players with poten- Player positions were defensive ry sustained while playing football tial professional ability were evalu- back, defensive lineman, line- was reported by 231 players (72%). ated by various NFL teams and backer, offensive lineman, kicker/ They had a total of 287 foot and their respective medical staffs over punter, quarterback, running back, ankle injuries (1.24 injuries/play- a 4-day period. The data necessary tight end, wide receiver, and special er injured). Of these players, 102 for this study were collected during teams. Radiographic features and (44%) were defensive players, 123 each athlete’s medical evaluation. physical findings (range of motion, (53%) were offensive players, and 6 Three hundred twenty elite col- strength, stability, etc.) were used to (3%) were placekickers or special- lege football players were invited confirm and further define injury ists (Table I).

January 2011 41 Incidence and Variance of Foot and Ankle Injuries in Elite College Football Players

Table II. Summary of Injuries and Surgeries

Players With Total Surgery Players Total % of Surgery Surgeries Rate Injury (n) Injuries Players (n) (n) (%)

Lateral ankle sprain 100 115 31.3 3 3 2.6 Syndesmotic sprain 47 50 14.7 0 0 0.0 MTP dislocation/turf toe 35 36 10.9 4 4 11.1 Fibular fracture 24 25 7.3 11 12 48.0 Jones fracture 17 17 5.3 10 10 58.8 Lisfranc sprain 11 12 3.4 0 0 0.0 Medial ankle sprain 7 7 2.2 1 1 14.3

Abbreviation: MTP, metatarsophalangeal.

Table III. Common Foot and Ankle Injuries by Player Position Player Position Injury DL DB K/P LB OL QB RB ST TE WR Total

Players (n) 54 59 4 36 50 25 29 2 21 40 320 Players with surgery (n) 6 2 1 4 7 3 7 1 4 5 40 Lateral ankle sprain 18 20 3 12 10 5 7 1 7 17 100 Syndesmotic sprain 9 9 0 5 16 1 3 1 2 1 47 MTP dislocation/turf toe 4 5 0 5 5 3 5 0 3 5 35 Fibular fracture 3 3 0 3 3 4 4 0 2 2 24 Jones fracture 5 1 1 1 5 1 0 1 1 1 17 Lisfranc sprain 2 1 0 1 3 0 2 0 1 1 11 Medial ankle sprain 0 0 0 0 3 0 3 0 1 0 7

Abbreviations: DB, defensive back; DL, defensive lineman; K/P, kicker/punter; LB, linebacker; MTP, metatarsophalangeal; OL, offensive lineman; QB, quarterback; RB, running back; ST, special teams; TE, tight end; WR, wide receiver.

Table II lists the most com- linemen (9/54, 17%), with statisti- The most common surgery was mon foot and ankle injuries: lat- cal significance found for offen- open reduction and internal fixa- eral ankle sprain (100 players, 115 sive linemen as compared with the tion (ORIF) of a fractured ankle, injuries), syndesmotic sprain (47 other positions. MTP dislocation/ comprising 26% of the surgical players, 50 injuries), metatarsopha- turf toe injuries were also common, procedures. The 12 players who had langeal (MTP) dislocation/turf toe affecting 35 of 320 players (11%). undergone ankle ORIF included 3 (35 players, 36 injuries), and fibular These injuries were seen most often linebackers and 3 running backs. fracture (24 players, 25 injuries). in running backs (5/29, 17%), tight Ten players, including 3 offensive Players often fell into 2 or more ends (3/21, 14%), and lineback- linemen, had undergone ORIF of of these groups, having sustained ers (5/36, 14%). Quarterbacks sus- a Jones fracture. separate injuries. Kickers/punters tained more fibular fractures (16%) (100%), special teams (100%), run- than other players did. Discussion ning backs (83%), wide receivers Overall, 40 players (26 offensive Foot and ankle injuries are com- (83%), and offensive linemen (80%) players, 12 defensive players, 1 place- mon in collegiate football players. sustained the highest incidence of kicker, 1 specialist) underwent 46 sur- Annual incidence has ranged from foot and ankle injuries, quarter- geries (Table I). Specialists (1/2, 50%), 9% to 39% in epidemiologic stud- backs (52%) and tight ends (62%) placekickers (1/4, 25%), and running ies,4-8,10,11 but, in the present study, the lowest (Table I). backs (7/29, 24%) had the highest 72% of players presented to the Lateral ankle sprains were by far percentage of players with a history 2006 NFL Combine with a history the most common injury, affecting of foot or ankle surgery, though the of foot or ankle injury. The foot 31% of players, including 17 (43%) first 2 groups were small in number. and ankle are highly susceptible of the 40 wide receivers (Table Only the percentage of running backs to injury in football players with III). A history of a syndesmotic who had undergone surgery (24%) increasing exposure and may be at injury was documented in 47 (15%) was significantly higher than that of higher risk as opponents become of all 320 players. Syndesmotic other players (c2 = 3.1). Defensive stronger and more skilled. sprains were most common in spe- backs had the lowest percentage of Another study by our group dem- cialists (1/2, 50%), offensive line- players with a history of foot or ankle onstrated that a history of previous men (16/50, 32%), and defensive surgery (3.4%, c2 = 3.9). shoulder injury was a risk factor for 42 The American Journal of Orthopedics® L. D. Kaplan et al repeated injury (mean, 1.3 shoul- undergone surgery for foot or position or specific activity. Also, der injuries/player injured).9 In a ankle injury repair (24%, 7/29) this study provides only a snapshot subsequent study by our group, may indicate that these athletes of accumulated injuries during a recurrent knee injuries were also sustain more severe injuries than single Combine. It also is possible common (mean, 1.3 injuries/player other players do. that some of the injuries may have injured).21 In the present study, we Although running backs were occurred outside football-related found a similar rate: 1.24 injuries more likely to have sustained a activities. Our sample size is rela- to the foot and ankle per player lateral ankle sprain, offensive tively small, which could prevent injured. Brophy and colleagues16 linemen presented with a higher trends in injury patterns from found ankle sprains to be the most percentage of syndesmotic ankle reaching significance. This is a par- common injury for any anatomical sprains. This trend may be related ticular problem in positions with site in 6 of 9 of the player posi- to the mechanism of injury; run- only a few players, such as kick- tions and the second most com- ning backs engage in more open- ers and punters, at the Combine.

“The higher risk to the foot and ankle in the ‘skill positions’ may be related to the increased cutting and direction changes required by these players.” mon injury in 2 other positions. field cutting maneuvers and are Elite college players whose injuries This finding is consistent with ours: required to change direction at were severe enough to prevent them Ankle sprains were by far the most high speeds, which may lead to from progressing to the level of common foot and ankle injuries. inversion of the ankle. Lateral the Combine automatically were Our results also support the find- ankle sprains often are caused by excluded from this study, likely caus- ings by Turbeville and colleagues19 an inversion mechanism, consis- ing us to underestimate both injury that previous injury is a risk factor tent with our findings. Linemen incidence and injury severity. Our for more injury. The ability to pre- are more often involved in pile- data collection method allows for dict and prevent recurrent injuries ups that lead to blows to the significant recall bias. Much of the is important not only to maximize leg with a planted foot, leading information used in this study was playing time but to prevent future to internal rotation of the body provided directly by the athletes, degenerative joint disease. Moretz around a fixed, dorsiflexed foot. which raises concerns that players and colleagues22 found a signifi- Syndesmotic sprains are thought may minimize the effects or severity cantly higher rate of knee osteo- to be caused by external rotation of their injuries for fear that they arthritis in athletes who sustained and/or hyperdorsiflexion, again may reduce their value as a profes- a knee injury during high school consistent with our findings.23 sional football player. Every effort football 20 years earlier. At the Combine, quarterbacks was made to obtain a thorough Foot and ankle injuries occurred had the lowest percentage of players medical history and perform a com- more often in offensive players, with previous foot or ankle injury plete physical examination and to with running backs, wide receivers, (52%, 13/25). This lower rate may correlate these with any available and offensive linemen all report- be related to lack of contact with imaging studies to minimize this ing high incidence. Canale and opposing players in a significant effect as much as possible, but it can- colleagues3 also found running percentage of plays. not be completely eliminated. backs, fullbacks in particular, to Study Limitations. Our study be the most prone to overall injury, has important limitations. It was Conclusions though other studies have found designed to identify associations This study shows that foot and that injuries were most likely in between player position and injury ankle injuries are very common in linemen.5,9,17,19,20 The higher risk type. Information on the type of elite collegiate American football to the foot and ankle in the “skill play, playing conditions, and time players, affecting 72% of the play- positions” may be related to the lost for each injury was not col- ers in our study group. However, increased cutting and direction lected. In addition, data on injuries most injuries did not lead to sur- changes required by these play- sustained during special teams play gery. Our data illustrate the influ- ers and to the increased risk for were not analyzed independently. ence of player position on type of a twisting injury during tackling. This information could be valu- foot and ankle injuries sustained The significantly higher percent- able to understanding the asso- and may be used to try to antici- age of running backs who have ciations of the injuries with player pate and avoid these injuries. January 2011 43 Incidence and Variance of Foot and Ankle Injuries in Elite College Football Players

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44 The American Journal of Orthopedics®