Introduction: Anatomical observation and biomechanical studies have shown that the anterior cruciate ligament (ACL) mainly consists of two distinct bundles, the anteromedial (AM) bundle and posterolateral (PL) bundle. Conventional single-bundle ACL reconstruction techniques have focused on the restoration of the AM bundle while giving limited attention to the PL bundle. The purpose of this prospective, randomize clinical study is to compare the outcomes of ACL reconstruction when using either double-bundle or single-bundle technique and bioabsorbable interference screw fixation, and similar rehabilitation, with both techniques.
Methods: Sixty-five patients were randomized into either double-bundle (n = 35) or single-bundle (n=30) ACL reconstruction with hamstring tendons and bio-absorbable screw (Hexalon, Inion Company, Finland) fixation in both group. The evaluation methods were clinical examination, KT-1000 arthrometer measurements, radiographic evaluation, as well as International Knee Documentation Committee (IKDC), and Lysholm knee scores. There were no differences between the study groups preoperatively. For an average of 14 months of follow-up (range, 12 to 20 months), 30 patients of the double-bundle group and 29 patients of the single-bundle group were available (91%).
Results: At the follow-up, the rotational stability, as evaluated by pivot shift test, was significantly better in the double-bundle group than in the single-bundle group. Also, the early anterior stability tended to be better with double-bundle technique, although at the 14-month follow-up, no significant difference between the groups was found anymore. In addition, none of the patients in the double-bundle group had graft failure, while four patients in the single-bundle group had. However, knee scores were equal at the follow-up, and all the results were significantly better at the follow-up than preoperatively, in both groups.
Conclusions: Rotational stability and early anterior stability were better with double-bundle technique than with single-bundle technique in ACL reconstruction with hamstring autografts and bioabsorbable screw fixation. However, both fixation techniques improved patients’ performance.
