Previous foot injuries associated with a greater likelihood of Achilles tendon ruptures in professional American football players

Objectives: The purpose of this study was to build on current understanding of Achilles tendon (AT) ruptures in football through the examination of lower extremity injury rates (IR) in the season prior to AT rupture. Methods: An online review was conducted to document AT ruptures in the National Football League (NFL) from the 2010-11 through 2016-17 seasons. Player-specific information was gathered through the online search, injury reports, or video analysis. Injury incidence was recorded for each season. Descriptive statistics were calculated for all variables. IRs per 1000 athlete-exposures with 95% confidence intervals (CI) were established. Injury rate ratios (IRR) with 95% CI were calculated to evaluate differences in IR with statistical significance established at p < 0.05. Results: From the 2010-11 to 2016-17 NFL seasons, 109 AT ruptures were identified. 36 athletes participated in the NFL the season prior and sustained a total of 40 injuries. Thirty-two (32/40, 80%) of the injuries involved the lower extremity. The most frequent body parts injured in the NFL season prior to AT rupture were the knee (n = 8, 22.5%), upper leg and thigh (n = 7, 17.5%), lower leg and shin (n = 5, 12.5%), and ankle (n = 5, 12.5%). The overall IR for the AT rupture group was not significantly different than the NFL group (IRR: 0.94, 0.68-1.31 95% CI, p = 0.73). The AT rupture group demonstrated a significantly increased rate of foot injuries compared to the NFL cohort (IRR: 2.58, 1.16-5.77 95% CI, p = 0.02). Conclusion: There was an increased identified incidence of AT ruptures in the NFL from 2010 to 2017 compared to AT ruptures reported from 1997 to 2002. There was no significant difference in lower extremity IR the season prior to AT rupture. Only foot injuries demonstrated an increased IR the season prior to AT rupture compared to an NFL cohort. Eleven athletes sustained 2 AT ruptures and all 11 players sustained the subsequent AT rupture to the contralateral limb.