Assessment of Return to Sport After ACL Reconstruction With Soft Tissue Autograft in Adolescent Athletes: Quadriceps Versus Hamstring Tendon

BACKGROUND: Quadriceps tendon soft tissue autograft represents an increasingly popular graft option for anterior cruciate ligament reconstruction (ACLR), particularly for adolescents, some of whom have an open physis, precluding use of graft options with bone plugs. PURPOSE/HYPOTHESIS: The purpose of this study was to quantify return-to-sport performance assessments in adolescents at 6 months after ACLR with all–soft tissue quadriceps tendon autograft (ACLR-Q) versus hamstring tendon autograft (ACLR-HS). It was hypothesized that ACLR-Q would be associated with improved hamstring strength and hamstring-to-quadriceps (HS:Q) ratios compared with ACLR-HS, albeit with decreased quadriceps strength. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Included were patients aged 12 to 19 years who underwent primary ACLR by a single surgeon and who completed a return-to-sport performance assessment between 5 and 9 months postoperatively. The performance assessment included manual muscle strength tests (hamstring, quadriceps, hip abductor and adductor), dynamic balance test (Y-balance), and functional hop tests (single hop, triple hop, crossover hop, 6-m timed hop). Data were converted to limb symmetry indices, and limb symmetry index deficits were compared between the ACLR-Q and ACLR-HS cohorts using the Student t test or Wilcoxon-Mann-Whitney test. RESULTS: An initial cohort of 90 ACLR-Q patients was compared with 54 ACLR-HS patients, with no significant differences in patient characteristics. Differences in meniscal repair rates, however, prompted use of propensity score matching on age, sex, body mass index, meniscectomy, and meniscal repair to produce comparable subcohorts. The matching resulted in 67 ACLR-Q and 52 ACLR-HS patients. Hamstring strength deficits were significantly greater in ACLR-HS versus ACLR-Q patients (−40.5% vs −5.7%; P < .001). Quadriceps strength deficits were significantly greater in ACLR-Q versus ACLR-HS patients (−12.8% vs −0.4%; P < .001). ACLR-Q patients had a significantly greater HS:Q ratio on the operative knee (P < .001) and significantly higher Y-balance composite score deficits (−2.9% vs −0.4%; P = .01) than ACLR-HS patients. There were no significant differences in hop test performance between groups. CONCLUSION: Adolescent athletes who underwent ACLR-Q showed significantly greater quadriceps strength deficits but significantly smaller hamstring strength deficits than those who underwent ACLR-HS, leading to more favorable HS:Q ratios in ACLR-Q patients at 6 months postoperatively.