Outcomes Following Bone-patellar Tendon-Bone Anterior Cruciate Ligament Reconstruction In Patients <30 Years: Allograft Vs. Autograft

Abstract

PURPOSE: The purpose of this study was to investigate differences in failure rates and functional outcomes between patients <30 years of age that underwent allo- or autograft Bone-Patellar Tendon-Bone (BPTB) ACLR. METHODS: All patients aged 16-30 years who underwent a BPTB allo- or autograft ACLR with bioabsorbable interference screws by a single surgeon (1995-2019) were included. Exclusion criteria were follow-up <2 years, osteochondral drilling, revision ACLR, and multi-ligamentous injuries. The allograft was always <5 years than patient age and not terminally irradiated. Meniscal repairs were completed as necessary. All patients completed a decelerated, conservative rehab program with required bracing for 3 months and return to pivoting sports >6 months. An independent physical exam including knee ROM and stability testing, (manual max KT-1000, Lachman, pivot shift) was performed. Patients completed Lysholm, IKDC, Tegner and pain Visual Analogue Score (VAS) to assess clinical outcomes. Failure was defined as positive Lachman or pivot shift test or MRI evidence of re-tear. RESULTS: 13 patients with BPTB allograft (5 male/8 female; 24.3 ± 4.0 years) and 35 patients with BPTB autograft (28 males/7 females; 22.3 ± 4.2 years) ACLR were included (p = 0.136). Average follow-up was 11.7 ± 3.9 years in the allograft group and 13.9 ± 5.9 years in the autograft group (p = 0.685). There were no significant differences in functional outcomes between groups (Lysholm: p = 0.226; IKDC: p = 0.107; Tegner: p = 0.610). There was no significant difference in laxity between groups (KT-1000 30 lbs: p = 0.131; manual maximum: p = 0.416; side to-side difference 30 lbs: p = 0.310; side-to-side difference manual max: p = 0.472). All patients returned to preoperative sports (Tegner score ≥ 5). Overall failure rate was 1.8% (1/48) with 1 failure in the autograft group (p = 0.548). CONCLUSION: In this cohort of young patients, no difference in failure rate was seen between allograft and autograft. At a mean of >10-year follow-up, laxity and all patient reported outcomes were not different between the groups. Careful selection of an allograft for use in ACLR and a decelerated rehabilitation program can be a good alternative in young patients >30 years to return to preoperative sports with no evidence of increased failure rates in this cohort.