Similar Isokinetic Strength Preinjury and at Return to Sport after Hamstring Injury

INTRODUCTIONSide-to-side strength differences are often used in return to sport (RTS) decision making after hamstring injury. In football (soccer), there is little consensus, and a side-to-side difference of 95% compared with preinjury strength. Overall, 63.4% of the players had a >10% negative strength difference (i.e., the injured limb being weaker), and 57.9% of the players had a >10% positive strength difference (i.e., the injured limb being stronger) in at least one of the five isokinetic variables. CONCLUSIONThe distribution of isokinetic strength differences when comparing strength at RTS with preinjury measures was similar, urging clinical caution when interpreting these results. Small changes in the isokinetic strength of the injured limb at RTS compared with preinjury strength suggest that isokinetic cutoff values are not useful to guide the restoration of strength as a criterion for RTS after hamstring injury.