Summary

Femoral tunnel location affects on posteoperative knee laxity and clinical outcomes after single bundle ACL reconstruction

Abstract

Introduction

The purpose of this study is to evaluate whether a change in the femoral tunnel among posterior, center and anterior positions within anatomical femoral attachment site could affect the laxity and clinical outcomes.

Methods

72 patients undergoing single bundle ACL reconstruction with autologous hamstring tendon from April 2012 to August 2014 who were followed minimum 1 year were retrospectively reviewed. To analysis the femoral tunnel, postoperative 3D-CT was evaluated by the radiographic quadrant method of Bernard et al. All patients were divided 3 groups according to relative femoral tunnel positions within anatomical femoral attachment site (posterior vs center vs anterior). At follow up 1 year, all subjects were evaluated by stress radiography, GNRB knee arthrometer, pivot shift test to exact measurements of laxity. Clinically, Subjective International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm score were evaluated.

Results

In total, 15 patients in the posterior femoral tunnel group (Group A), 21 patients in the central femoral tunnel group (Group B) and 36 patients in the anterior femoral tunnel group (Group C) completed this study. At follow up 1 year, group A and B showed significantly reduced anterior laxity than group C (p=.0171). There were no significant differences in rotational instability among them (p=.0718). And we found that Group A and B was superior to group C in terms of clinical outcomes.

Conclusion

We concluded that it is most ideal to be located at anatomical center, but it is good to be located posteriorly within anatomical femoral attachment site without compromising laxity and clinical outcomes.