Abstract
BACKGROUND: Rehabilitation after repair of the anterior cruciate ligament (ACL) is complicated by the loss of leg muscle mass and strength. Prior studies have shown that preoperative rehabilitation may improve muscle strength and postoperative outcomes. Testosterone supplementation may likewise counteract this muscle loss and potentially improve clinical outcomes. PURPOSE: The purpose was to investigate the effect of perioperative testosterone administration on lean mass after ACL reconstruction in men and to examine the effects of testosterone on leg strength and clinical outcome scores. It was hypothesized that testosterone would increase lean mass and leg strength and improve clinical outcome scores relative to placebo. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Male patients (N = 13) scheduled for ACL reconstruction were randomized into 2 groups: testosterone and placebo. Participants in the testosterone group received 200 mg of intramuscular testosterone weekly for 8 weeks beginning 2 weeks before surgery. Participants in the placebo group received saline following the same schedule. Both groups participated in a standard rehabilitation protocol. The primary outcome was the change in total lean body mass at 6 and 12 weeks. Secondary outcomes were extensor muscle strength, Tegner activity score, and Knee injury and Osteoarthritis Outcome Score. RESULTS: There was an increase in lean mass of a mean 2.7 ± 1.7 kg at 6 weeks postoperatively in the testosterone group compared with a decrease of a mean 0.1 ± 1.5 kg in the placebo group (P = .01). Extensor muscle strength of the uninjured leg also increased more from baseline in the testosterone group (+20.8 ± 25.6 Nm) compared with the placebo group (-21.4 ± 36.7 Nm) at 12 weeks (P = .04). There were no significant between-group differences in injured leg strength or clinical outcome scores. There were no negative side effects of testosterone noted. CONCLUSION: Perioperative testosterone supplementation increased lean mass 6 weeks after ACL reconstruction, suggesting that this treatment may help minimize the effects of muscle atrophy associated with ACL injuries and repair. This study was not powered to detect differences in strength or clinical outcome scores to assess the incidence of testosterone-related adverse events. CLINICAL RELEVANCE: Supraphysiological testosterone supplementation may be a useful adjunct therapy for counteracting muscle atrophy after ACL reconstruction. Further investigation is necessary to determine the safety profile and effects of perioperative testosterone administration on leg strength and clinical outcomes after surgery. REGISTRATION: NCT01595581 (ClinicalTrials.gov).