Paper 26: Clinical Outcomes of Combined ACL and Anterolateral Ligament Reconstruction Versus Isolated ACL Reconstruction With Bone-Patellar Tendon-Bone Autograft As The Gold Standard: A Matched-Pair Analysis of 2018 Patients

OBJECTIVES: The aims of this study were to compare the clinical outcomes following “gold standard” ACL reconstruction (ACLR) with a Bone-Patellar Tendon-Bone (BPTB) autograft versus ACLR combined with an anterolateral ligament reconstruction (ALLR) using hamstring tendon autografts (HT), in a large series of propensity matched patients. The hypothesis was that combined ACLR+ALLR would confer better graft rupture rates and lower non-graft rupture related re-operation rates than isolated ACLR with BPTB METHODS: A retrospective analysis of prospectively collected data was performed. Patients undergoing ACLR+ALLR using HT between January 2003 and December 2019 were propensity matched in a 1:1 ratio to patients undergoing isolated ACLR using BPTB. At the end of the study period rates of graft rupture and any other re-operations or complications that occurred following the index procedure were identified by database interrogation, review of medical records and standardized telephone interview. Kaplan Meier survivorship analyses and Cox-proportional hazards models were used to evaluate graft survivorship, re-operation free survivorship and the significance of potentially important risk factors. RESULTS: A total of 2018 patients (1009 matched pairs) were included. The mean duration of follow-up was 101.3 months. Kaplan Meier Analysis demonstrated a significantly better graft survivorship in the ACLR+ALLR group when compared to the BPTB group at every time point (Fig 1 and Table 1). The Cox model demonstrated that patients in the BPTB group were > 3-fold more likely to experience graft failure (Hazard Ratio (HR) = 3.554 [1.744;7.243], p = 0.0005). Patients aged less than 20 years were at particularly high risk of graft rupture (HR = 5.65 [1.834;17.241], p = 0.0002) and further analysis of this subgroup demonstrated that isolated ACLR with BPTB also conferred a > 3 fold increased risk of graft rupture in young patients when compared to ACLR+ALLR. Multivariate analysis did not identify any other significant risk factors for graft rupture. Overall, there was a significantly higher reoperation rate following isolated ACLR (BPTB group 20.5%, ACLR+ALLR group 8.9%, p < 0.0001). This finding was accounted for by significantly higher rates of graft rupture (9.9% vs 3.5%, p <0.0001), cyclops syndrome (3.3% vs 1.5%, p <0.0001), and secondary meniscectomy (5% vs 2.9%, p=0.0196) in the BPTB group. CONCLUSIONS: Patients who underwent isolated ACLR with BPTB autografts experienced significantly worse ACL graft survivorship and overall re-operation free survivorship when compared to those who underwent combined ACLR+ALLR with hamstring autografts. The risk of graft rupture was more than 3-fold higher in patients who underwent isolated ACLR using BPTB.