Identification of previous hamstring muscle injury by isokinetic concentric and eccentric torque measurement in elite soccer player

Abstract

Twenty-eight elite soccer players (23 years ± 3.3; 74 kg ± 7.5; 178 cm ± 6.5) were tested to find out whether isokinetic parameters could identify sportsmen who had previously suffered from hamstring muscle injury. Eleven players with 15 previous moderate or major hamstring muscle injuries in the preceding 2 years were compared with 17 controls. Strength was measured using a Cybex Norm isokinetic dynamometer on a concentric and eccentric contraction at the angular speed of 60°/s. An ipsilateral concentric Hamstring-to-Quadriceps ratio lower than 0.6 and an eccentric hamstring asymmetry of more than 10% did not enable identification of soccer players with previous hamstring muscle injury. On the other hand, concentric hamstring torque asymmetry of more than 10% identified the uninjured soccer players (probability of 90.1%). A dynamic control ratio (eccentric hamstring-to-concentric quadriceps) lower than 0.6 provided the best predictor of previous hamstring muscle injury (probability of 77.5%). In conclusion, concentric and eccentric isokinetic evaluation of hamstring muscle at the speed of 60°/s renders the search for previous hamstring muscle injury possible by revealing muscle torque asymmetry, which persists despite the resumption of competitive soccer.