LOWER REVISION RATE WITH BONE-PATELLAR TENDON-BONE AUTOGRAFT COMPARED TO BOTH QUADRICEPS AND HAMSTRING TENDON AUTOGRAFTS: RESULTS FROM THE NEW ZEALAND ACL REGISTRY

Introduction The use of hamstring tendon (HT) autografts in anterior cruciate ligament (ACL) reconstruction has reduced in New Zealand after registry data demonstrated a higher revision rate. In contrast, the use of quadriceps tendon (QT) autografts has increased, but it is unclear whether it has a lower revision rate than the bone-patellar tendon-bone (BTB) autograft. Methods Prospective data from the New Zealand ACL Registry were analyzed. Primary ACL reconstructions performed between 2014 and 2022 with a minimum follow-up of two-years were eligible. The primary outcome was revision. Secondary outcomes included patient-reported kneeling difficulty, the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Marx activity score. Multivariable analysis was performed via Cox regression survival analysis to calculate hazard ratios (HR) adjusted for age, gender, timing of surgery and meniscal injuries. Results 15,687 primary ACL reconstructions were analyzed, of which 4,424 used a BTB graft (28%), 574 used a QT graft (4%) and 10,689 used a HT graft (68%). The BTB graft had the lowest revision rate of 3.1% compared to 4.4% with the QT graft and 6.1% with the HT graft (p<0.001). On multivariable analysis, the QT graft (HR = 1.7, p = 0.01) and the HT graft (HR = 2.3, p<0.001) had a higher risk of revision when compared to the BTB graft. The BTB graft had the highest incidence of kneeling difficulty at 2-year follow-up (16.4%) when compared to the QT (13%) and HT (9.8%, p<0.001) grafts. Despite this, the BTB graft had better KOOS and Marx activity scores when compared to the QT and HT grafts. Discussion/Conclusion The BTB graft has a lower revision rate than both the QT and HT grafts. Patients with a BTB graft are more likely to report difficulty with kneeling, but still report better KOOS and Marx activity scores at 2-year follow-up.