Comparison of Patellar Tendon and Hamstring Grafts in ACL Reconstruction: Patellar Tendon Shows Lower Re-Rupture Rates in High-Risk Groups but Comparable Outcomes in Low-Risk Patients

Purpose To compare re-rupture rates and clinical outcomes between bone–patellar tendon–bone (BTB) and hamstring tendon (HT) grafts in anterior cruciate ligament (ACL) reconstruction according to patient risk levels. Methods This retrospective cohort study included patients who underwent primary ACL reconstruction at a single institution between 2018 and 2022, with a minimum of two years of follow-up. High-risk patients were defined as those aged ≤ 20 years, with posterior tibial slope ≥ 12°, and participating in pivoting sports. In this group, re-rupture rates and Knee injury and Osteoarthritis Outcome Score (KOOS) were compared between the BTB and HT grafts. For patients with two or fewer risk factors, propensity score matching was performed to compare outcomes. Results In the high-risk group, the BTB graft showed a significantly lower re-rupture rate compared to the HT graft (12.9% vs. 35.7%, p = 0.03), with no significant difference in KOOS (96.3 ± 3.7 vs. 96.6 ± 6.3, p = 0.85). In the lower-risk group after matching, the BTB graft showed a similar re-rupture rate compared to the HT graft (8.2% vs. 6.8%, p = 0.99), with no significant difference in KOOS (94.5 ± 5.0 vs. 94.9 ± 6.6, p = 0.73). Conclusion BTB grafts reduced re-rupture rates compared to HT grafts in high-risk ACL reconstruction patients, while clinical outcomes were similar. In lower-risk patients, no significant differences were observed between graft types in either re-rupture rates or KOOS. Level of Evidence Level III