No difference in initial fixation or 1-year outcomes with outside in metallic or bioabsorbable interference femoral screws in rectangular tunnel bone-patellar tendon-bone graft for anterior cruciate ligament reconstruction

Abstract

ObjectivesTo compare the rate of initial fixation failure and clinical outcomes in anterior cruciate ligament reconstruction (ACL-R) surgery with a rectangular tunnel bone-patellar tendon-bone (RT-BTB) graft (RT-BTB ACL-R) using metallic interference screws (M-IFSs) and bioabsorbable interference screws (B-IFSs) for femoral fixation.MethodsData were prospectively collected from patients undergoing RT-BTB ACL-R and CT within 2 weeks after surgery. Femoral fixation was performed using M-IFSs (M-IFS group) or B-IFSs (B-IFS group). Screw selections were historically controlled. The following parameters were intraoperatively assessed: IFS breakage and initial fixation failure examined by movement of the graft pulled with maximum manual force. Posterior wall breakage was assessed using CT. Lysholm Score, the 2000 International Knee Documentation Committee Knee Examination Form and the KT-2000 arthrometer was evaluated as the clinical outcome measures.ResultsThe study included 116 patients. Of these, 26 were included in the M-IFS group and 92 in the B-IFS group. The rate of IFS breakage was not significantly different between the M-IFS and B-IFS groups (0.0% vs 2.2%). The rate of initial fixation failure was not significantly different between the M-IFS and B-IFS groups (3.8% vs 5.6%). Logistic regression analysis revealed that only posterior wall breakage predicted initial fixation failure (p=0.02). No significant difference of the clinical outcomes was observed between the M-IFS and B-IFS groups.ConclusionInitial fixation failure or clinical outcomes is not different between M-IFS and B-IFS use for femoral fixation in RT-BTB ACL-R.Level of evidenceProspective study using historical controls, level IV.