Cortical Suspensory Button Versus Aperture Interference Screw Fixation for Knee Anterior Cruciate Ligament Soft-Tissue Allograft: A Prospective, Randomized Controlled Trial

Abstract

Purpose: To compare anterior cruciate ligament (ACL) soft-tissue allograft reconstruction using suspensory versus aperture fixation.

Methods: After we performed prospective power analysis and obtained institutional review board approval, as well as patient consent, 64 patients were block randomized among 3 study sites to the aperture fixation group or suspensory fixation group. All patients underwent all-inside ACL reconstruction with soft-tissue allograft using either (1) femoral and tibial joint-line fixation with a femoral cannulated interference screw and a tibial cannulated interference retrograde screw (aperture) or (2) femoral and tibial cortical buttons (suspensory). Our primary outcome measure was knee anteroposterior (AP) stability measured using the KT-1000 device (MEDmetric, San Diego, CA). Secondary outcome measures included change in pain score on a visual analog scale versus preoperatively, narcotic consumption, International Knee Documentation Committee knee examination rating, International Knee Documentation Committee subjective evaluation score, Knee Society Scores, Short Form 12 scores, and radiographic analysis for socket widening.

Results: Ultimately, 6 included patients (9%) were not treated (cancelled surgery), and at 2 years' follow-up, 43 treated patients (74%) completed clinical evaluation. The primary outcome measure, instrumented knee AP stability at 25° of knee flexion, showed no difference between groups (P = .61) at 24 months' follow-up. In addition, no statistically significant difference between groups was observed for secondary measures.

Conclusions: Our results show no significant differences in knee AP stability or other outcomes comparing all-inside ACL allograft reconstruction using aperture fixation and all-inside ACL allograft reconstruction using suspensory fixation.

Level of evidence: Level II, lesser-quality randomized controlled trial with follow-up of less than 80% at 2 years.