Factors impacting time to reach return-to-sport benchmarks following ACL reconstruction

Timing of return to sport (RTS) after anterior cruciate ligament reconstruction (ACLR) is a multifaceted decision for athletes. The purpose of this study was to identify patient-related predictors (age, sex, graft type, psychological readiness, and the duration of physical therapy (PT) of time to pass RTS criteria.

Fifty-four participants within 5-15 months of ACLR completed testing as part of RTS planning, including quadriceps strength (isometric and 1-repetition maximum using a knee extension machine), 4 single leg hop tests (single, crossover, triple, and 6-meter timed), and patient-reported knee function (International Knee Documentation Committee Subjective Knee Form 2000 [IKDC], Global Rating Scale [GRS] and the Anterior Cruciate Ligament Return-to-Sport after Injury scale [ACL-RSI]). Passing RTS testing required ≥90% on each test (except ACL-RSI). Multivariate linear regression was used to assess the association between patient factors and time to pass RTS testing. An alpha level of p < 0.05 was set a priori.

Mean time to pass RTS testing was 10.3 ± 2.6 months. Regression analysis showed that sex (β = 0.408; p < 0.001) and graft type (β = 0.365; p = 0.002) were significant predictors, explaining 47.5% of the variance in RTS timing. Males passed an average of 2.6 months earlier than females (9.0 ± 1.8 vs. 11.6 ± 2.6 months). Hamstring, allograft, or IT band autograft recipients passed earlier (7-9 months) than quadriceps or patellar tendon autografts (11-12 months).

Female participants and those with a patellar or quadriceps tendon graft took longer to meet objective RTS criteria after ACLR.