Delayed Rehabilitation Is Associated with Recurrence and Higher Medical Care Use after Ankle Sprain Injuries in the United States Military Health System

OBJECTIVE: To investigate the influence of time taken to begin musculoskeletal rehabilitation on injury recurrence and ankle-related medical care use at 1 year after ankle sprain. DESIGN: Retrospective cohort study of all beneficiaries of the US Military Health System seeking care for an ankle sprain over a 4-year period. METHODS: Individuals were classified according to whether they did or did not receive physical rehabilitation. For those who received rehabilitation (n = 6150), linear relationships (with appropriate covariate controls) were analyzed with generalized linear models and generalized additive models to measure the effects of rehabilitation timing on injury recurrence and injury-related medical care use (costs and visits) at 1 year after injury. The nonlinear effect of rehabilitation timing on the probability of recurrence was assessed. RESULTS: Approximately 1 in 4 people received rehabilitation. The probability of ankle sprain recurrence increased for each day that rehabilitation was not provided during the first week. The probability of ankle sprain recurrence plateaued until about 2 months after initial injury, then increased again, with 2 times greater odds of recurrence compared to those who received physical rehabilitation within the first month. When rehabilitation care was delayed, recurrence (odds ratio [OR] = 1.28), number of foot/ankle-related visits (OR = 1.22), and foot/ankle-related costs increased (OR = 1.13; up to $1400 per episode). CONCLUSION: The earlier musculoskeletal rehabilitation care started after an ankle sprain, the lower the likelihood of recurrence and the downstream ankle-related medical costs incurred.