The Epidemiology of Ankle Injuries Identified at the National Football League Combine, 2009-2015

BACKGROUND: American football is a leading cause of sports-related injuries, with the knee, ankle, and shoulder most commonly involved. PURPOSE/HYPOTHESIS: The purpose of this study was to describe the epidemiology, characteristics, and imaging findings of ankle injuries in football players at the National Football League (NFL) Combine and determine the relationship to player position. We hypothesized that there would be a high relative incidence of ankle injuries in these players compared with other sports and that there would be a direct correlation between the incidence of ankle injuries and player position. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A retrospective chart review of data collected from NFL Combine participants between 2009 and 2015 was performed. Patient demographics, history, physical examination results, and imaging findings were reviewed. RESULTS: Of 2285 players, 1216 (53.2%) had a history of ankle injuries; of these, 987 (81.2%) had unilateral injuries, while 229 (18.8%) had bilateral injuries (total of 1445 ankles injured). This included 1242 ankle sprains (86.0% of ankle injuries): 417 (33.6% of sprains) high and 930 (74.9%) low. The most common soft tissue injuries were to the anterior talofibular ligament (n = 158, 12.7% of sprains) and syndesmosis (n = 137, 11.0%). Of all players at the NFL Combine with radiographs, 131 (10.9%) had evidence of an ankle fracture, all of which had healed. Magnetic resonance imaging (MRI) identified 66 players (28.9% of players at the combine who underwent MRI) with articular cartilage injuries: 62 involving the talus and 16 involving the tibia. Furthermore, 85 players (37.3% of players with MRI) with tendon injuries were identified: 26 Achilles, 55 peroneal, 3 flexor hallucis longus, and 19 posterior tibial. A total of 611 players (50.6% of players with radiographs) had signs of arthrosis on radiography. Running backs (61.9%), offensive linemen (60.3%), and tight ends (59.4%) had the highest rates of ankle injuries by position, while kickers/punters (23.3%) and long snappers (37.5%) had the lowest. CONCLUSION: Prior ankle injuries were present in more than 50% of elite college football players attending the NFL Combine. The rate of these ankle injuries varied by player position: offensive linemen, running backs, and tight ends had the highest overall rates, while special teams players had the lowest. Additional prospective work is needed to determine the impact of prior injuries on future playing career.