A Prospective, Randomized, Blinded, Comparison of Double-bundle Vs Anatomic Single Bundle Anterior Cruciate Ligament (ACL) Reconstruction using Hamstring Tendons, Average Seven Year Follow-Up

Aim: Compare results of, anterior cruciate ligament (ACL) reconstruction using double bundle (DB) technique Vs anatomic single bundle (SB), at a minimum six year follow-up.

Methods: Patients with unilateral instability of the knee, associated with rupture of the ACL, undergoing ACL reconstruction were randomized for either SB or DB ACL reconstruction using hamstring tendons. Postoperative rehabilitation protocol was the same for SB and DB reconstruction. Subjective evaluation was based on Lysholm questionnaire and Short Form 36 questions (SF36). A blinded examiner measured the anterior laxity and KT1000 difference in 30 degrees of flexion between the operated knee and the healthy knee, 3 months, 6 months, 1 year & 2 years post Op. Functional Tests (Single & Triple Hop Tests) at 6 months, 1& 2 years post Op. A telephone survey was conducted at a minimum of six years follow-up.

Results: A total of 63 patients were enrolled in the study, 30 in the DB group and 33 in the anatomic SB. Average age for the SB group was 23 years (range 18-31), and for the DB was 24 years (range 19-31), the majority of patients in both groups were males. Average follow-up was 90 months (range 73-106), with 79% follow-up rate. There were no statistical differences between groups regarding demographics and intra-operative pathologies. Patients were evaluated by an orthopedic surgeon and physiotherapist that were blinded to the surgical technique. At the last follow-up which was performed via phone there was no difference between the groups in all the measurements.

Conclusion: In this long term, prospective, randomized study both single bundle and double bundle anatomic ACL reconstruction resulted in improved patients score and function. However, double-bundle ACL reconstruction did not show any advantages over single-bundle ACL reconstruction either in clinical outcomes or in knee stability.