Comparison Between Single- and Double-Bundle Anterior Cruciate Ligament Reconstruction With 6- to 8-Stranded Hamstring Autograft

Abstract

Background: Whether double-bundle (DB) anterior cruciate ligament (ACL) reconstruction with 6- to 8-stranded hamstring autograft (HG) is better than single-bundle (SB) ACL reconstruction remains debatable, as long-term follow-up data are lacking. Purpose: To prospectively investigate and compare the long-term results of DB and SB ACL reconstruction with a 6- to 8-stranded HG. Study Design: Randomized controlled clinical trial; Level of evidence: 1. Methods: A total of 80 patients with chronic ACL rupture were randomized to SB or DB ACL reconstruction with a 6- to 8-stranded HG. In the SB group, both the semitendinosus tendon (ST) and the gracilis tendon (GT) were prepared in 3 or 4 strands, with a total of 6 to 8 strands. In the DB group, the ST was prepared in 3 or 4 strands used for the anteromedial bundle, and the GT was prepared in the same manner for the posterolateral bundle. Each graft was fixed with an EndoButton, a bioabsorbable interference screw, and a staple. Outcome assessment was performed by a blinded independent observer using International Knee Documentation Committee (IKDC), Tegner, and Lysholm scores, as well as range of motion (ROM), Lachman test, pivot-shift test, KT-2000 arthrometer side-to-side difference, and return-to-sport data. Results: A total of 68 patients (DB group, 34; SB group, 34) were observed for a mean of 80 months (range, 74-86 months). There were 2 traumatic instability failures and two 5° extension restrictions in the DB group, while no failures or 5° extension restrictions were observed in the SB group. The mean Lysholm, Tegner, and IKDC scores improved significantly in both groups compared with preoperation scores ( P < .05). No patient had a positive Lachman test result. No significant differences were found between groups in functional scores, incidence of pivot shift, ROM, Lachman test, KT-2000 arthrometer anterior laxity, or time and level of return to sport. Conclusion: Both SB and DB ACL reconstruction with 6- to 8-stranded HG showed satisfactory results in subjective scores and anteroposterior and rotational stability over a nearly 7-year follow-up; neither technique was superior.