Clinical predictors of time to return to competition following hamstring injuries.

OBJECTIVES hamstring strain injuries are the most common sports-related muscle injuries and one of the main causes of missed sporting events. HYPOTHESIS clinical findings reflecting hamstring injury severity at presentation predict time to sports resumption. DESIGN cohort study (prognosis); Level of evidence, 2. METHODS five sports medicine specialists at four sports medicine centers prospectively evaluated 120 athletes within 5 days of acute hamstring injury. Patients were interviewed and asked to evaluate their worst pain on a visual analog scale (VAS). Four physical criteria were assessed at baseline: bruising, tenderness to palpation, pain upon isometric contraction, and pain upon passive straightening. The same standardized rehabilitation protocol was used in all patients. A standardized telephone interview was conducted 45 days after the injury to determine the time to-full recovery (≤40 days or >40 days). RESULTS by univariate analysis, clinical criteria associated with a full recovery time >40 days were VAS pain score greater than 6, popping sound injury, pain during everyday activities for more than 3 days, bruising, and greater than 15° motion-range limitation. By multivariate analysis, only VAS pain score and pain during everyday activities were significantly associated with time to recovery >40 days (53% sensitivity, 95% specificity). CONCLUSION the initial examination provides valuable information that can be used to predict the time to full recovery after acute hamstring injuries in athletes.