Factors correlating with recovery of quadriceps strength after double-bundle anterior cruciate ligament reconstruction with hamstring tendon autografts.

Abstract

Recovery of quadriceps strength after anterior cruciate ligament (ACL) reconstruction is one of the criteria used to promote rehabilitation and return to play. The purpose of this study was to investigate the factors associated with recovery of quadriceps strength after ACL reconstruction with hamstring tendon autografts. Isokinetic quadriceps strength at 60°/s was measured preoperatively and 6 months after surgery in 101 patients (54 males and 47 females) who underwent double-bundle ACL reconstruction with hamstring tendon autografts. The quadriceps strength index (%) was calculated by normalizing the peak torque of the operated leg with that of the contralateral leg. Details on age, sex, body mass index, time from injury to surgery, pre-injury Tegner activity scale score, previous meniscus repair, and preoperative quadriceps strength index were recorded. The factors associated with the postoperative quadriceps strength index were investigated in univariate and multivariate regression analyses. Multivariate regression analysis showed that preoperative quadriceps strength index (p = 0.001) was independently associated with the quadriceps strength index at 6 months after surgery. There was a marginally significant inverse association between age and postoperative quadriceps strength, but no statistically significant association was found for any of the other factors investigated. Postoperative quadriceps strength index at 6 months after double-bundle ACL reconstruction with hamstring tendon autografts was affected by preoperative quadriceps strength index. Adequate preoperative quadriceps strength may need to be considered in order to facilitate better recovery of quadriceps strength after ACL reconstruction and to support an earlier return to sports activities.