ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION IN ≤21 YEAR OLDS: PATELLAR VERSUS HAMSTRING TENDON AUTOGRAFTS

BACKGROUND: Bone-patellar tendon-bone (BTB) and hamstring tendon (HS) are commonly used grafts for anterior cruciate ligament reconstruction (ACLR). The optimal graft choice for ACLR remains unclear. We evaluated clinical and self-reported outcomes of patients who underwent ACLR with use of a BTB autograft or double-bundle HS autograft/allograft-augmented HS autograft (HS hybrid). HYPOTHESIS/PURPOSE: No significant differences in outcomes exist between graft choices. METHODS: Retrospective review of prospectively collected data from patients aged ≤21 years who underwent primary ACLR with BTB or HS autograft/hybrid by one fellowship-trained orthopaedic surgeon and a minimum of 6 months follow-up. Demographics, injury characteristics, concomitant injuries, surgical and radiographic parameters were recorded. Clinical and patient self-reported outcomes (Tegner-Lysholm, pediIKDC, KOOSChild) were compared at 6-months, 1-year and latest follow-up. RESULTS: A total of 109 subjects were included; 59 had a HS graft (55 HS autograft, 4 HS hybrid) and 50 a BTB autograft. Patients were between 13 and 21 years old at ACLR and had a follow-up of 1.5 ±1 year. Baseline comparison of demographic, injury and surgical parameters is presented in Table1.1. Graft rupture occurred in 10 patients (9.2%; 9 males and 1 female) at an average of 2 years after initial ACLR; 8 graft ruptures occurred in the HS group (13.6%, none in HS hybrids) and 2 in the BTB group (4%) (p=0.105). Parameters increasing the likelihood of a re-tear were older age at ACLR (HR: 2.348, p<0.005), a >1-year delay to surgery (HR: 4.105, p=0.048) and a concomitant chondral injury (HR: 5.476, p=0.038) (Cox proportional hazards model, Table1.2). Arthrofibrosis developed in 4 BTB patients (8%) at an average of 6 months after initial ACLR, but not in HS patients (p=0.041). At most recent follow-up, patellofemoral pain was present in 15 (28%) HS and 5 (10%) BTB patients (p=0.027) and a contralateral ACL tear had occurred in 4 patients (3.7%). No differences were seen between graft groups for knee range of motion, Lachman testing, leg raise, ligament stability and subjective scores - Tegner-Lysholm, pediIKDC, KOOSChild (p>0.05 for each comparison at 6-months, 1-year and most recent follow-up). CONCLUSION: In patients <21 years undergoing ACLR, BTB autograft lead to fewer graft ruptures, however, was associated with a higher rate of arthrofibrosis. Older age at surgery, a delay to surgery and chondral injuries increased the likelihood of re-tear. However, failure rates were low, and we observed no differences between graft types in terms of laxity and patient self-reported outcomes. Tables/Figures: