Anteromedial (AM) and 2-incision are two commonly used techniques for drilling the femoral tunnel during ACL reconstruction. The purpose of this study was to compare clinical and radiographic outcomes of patients undergoing primary ACL reconstruction using either AM or 2-incision technique with minimum 2-year follow-up.
138 prospectively enrolled patients undergoing primary ACL reconstruction were divided into two groups based on femoral drilling technique and were evaluated pre-operatively, 6 weeks and 2 years post-operatively. Outcomes scores were collected at each visit using SF-36 PCS and MCS components, KOOS, and the Knee Activity Rating Scale.
48 patients underwent AM technique and 90 patients underwent 2-incision. Univariate analysis revealed no difference in pre-operative outcomes with the exception of AM group having higher KOOS Knee Pain (p=0.023) and Womac Pain (p=0.036). Following surgery, 2-incision femoral tunnels had a higher radiographic coronal angle (68.8°±8.6° vs 51.4°±11.3°; p<0.001) and clinical extension (1.2°±2.7 vs 2.9°±4.0°; p=0.010). There were no differences in knee flexion, complications, or re-rupture. There were also no differences clinical outcome scores with the exception of AM group having a higher 6-week and 2-year post-op KOOS ADL (p=0.030 and 0.050, respectively) and KOOS Womac (p=0.030 and 0.050, respectively), although likely not clinically relevant given the pre-operative differences. Multivariate analysis showed no clinical or outcome differences between AM and 2-incision techniques.
ACL reconstruction using the AM technique yielded lower radiographic coronal tunnel angle and slightly decreased knee extension. The theoretical risk of graft failure secondary to higher coronal angle leading to a “sawing” of the graft as it passes around a sharper femoral corner was not observed. Additionally, differences in pre-operative KOOS likely made post-operative differences irrelevant. We conclude there are no clinically relevant differences at 2 years in patients undergoing primary ACL reconstruction using either the AM or 2-incision femoral drilling techniques.
© 2016 Published by Elsevier Inc.