Does Gracilis Preservation Matter in Anterior Cruciate Ligament Reconstruction? A Systematic Review

Abstract

To analyze the effect of gracilis harvest on hamstring strength, patient-reported outcomes, and anterior knee laxity after anterior cruciate ligament (ACL) reconstruction. A systematic review of the literature was performed to identify studies comparing the results of semitendinosus (ST) versus semitendinosus-gracilis (ST-G) harvest for ACL reconstruction. A meta-analysis using a random effects model was performed to determine overall pooled estimates of effect for the influence of additional gracilis harvest on hamstring strength, patient-reported outcomes, and anterior knee laxity after ACL reconstruction. Twelve studies were identified and included in the review. ST-G harvest was noted to decrease hamstring isokinetic strength at 60° per second by 3.85% relative to isolated ST harvest (P= .01). Decreased isometric strength was also noted in the ST-G harvest group at both 90° of flexion (mean difference: 5.55%; P= .03) and 105° to 110° of flexion (mean difference: 13.68%; P= .003). Active knee flexion angle loss was also noted to be greater in the ST-G harvest group (mean difference: 3.91°; P= .006). No differences were found in isokinetic strength at 180° to 240° per second (mean difference: 3.20%; P= .08), patient-reported outcome scores (mean difference: 1.87 points; P= .06), or anterior knee laxity (mean difference: 0.03mm; P= .78) based on gracilis harvest. The addition of gracilis harvest to an isolated ST harvest for ACL reconstruction results in statistically significant, but likely not clinically relevant differences in isokinetic and isometric hamstring strength as well as patient-reported outcomes. Hamstring strength deficits may be larger at higher flexion angles. Level III, systematic review of level I-III studies.