Knee flexor strength following anterior cruciate ligament reconstruction with the semitendinosus and gracilis tendons

Knee flexor strength recovery following anterior cruciate ligament reconstruction with the doubled semitendinosus and gracilis tendons was assessed for up to 12 months post-Surgery. Twelve patients were followed up, four at 3 months, five at 6 months and three at 12 months post-surgery. Knee flexor moment was recorded using the Biodex System-3 isokinetic dynamometer. Three sets of five repetitions of reciprocal eccentric/concentric knee flexion contractions were carried out with each set at 1.05, 2.09 or 3.14 rad x s(-1). T-tests were used to test for significant differences between and within groups. The uninjured leg produced greater average peak moments than the injured leg; significant differences (p < 0.05) were seen between the legs at 1.05 rad x s(-1) for the 3-month group concentrically, and all three groups eccentrically. There was no significant difference (p > 0.05) between groups for the percentage deficit between legs. On average, a 23 % deficit in average peak moment was still evident at 12 months both eccentrically and concentrically at 1.05 rad x s(-1). Taken as a whole this evidence suggests that there is a deficit in knee flexor strength up to at least 12 months post-surgery following doubled semitendinosus and gracilis tendon graft reconstruction even after a full rehabilitation protocol.