A 5-Strand Hamstring Autograft Achieves Outcomes Comparable to Those of a 4-Strand Hamstring Autograft With a Graft Diameter of 8 mm or More in Anterior Cruciate Ligament Reconstruction

Background: Quadrupled (4-strand) hamstring tendon autografts are commonly used in anterior cruciate ligament (ACL) reconstruction, but there is significant variability in their diameter. The 5-strand hamstring autograft has been used as a means of increasing the graft diameter in patients with undersized hamstring grafts. Purpose: To report the outcomes of primary ACL reconstruction using 5-strand hamstring autografts in patients in whom the 4-strand configuration produced a graft diameter of <8 mm and to compare these outcomes with those of ACL reconstruction using 4-strand semitendinosus-gracilis autografts with a graft diameter of >= 8 mm. Study Design: Cohort study; Level of evidence, 2. Methods: The primary study group comprised 25 patients who underwent ACL reconstruction using a 5-strand hamstring autograft. The comparison group comprised 20 patients who underwent ACL reconstruction using a 4-strand hamstring autograft with a graft diameter of >= 8 mm. Interference screw fixation was used at the tibial and femoral ends for both groups of patients. Subjective questionnaires, including the Knee injury and Osteoarthritis Outcome Score (KOOS), the Lysholm score, and the Physical Component Summary and Mental Component Summary of the Short Form-36 (SF-36), were administered preoperatively as well as at 1- and 2-year follow-up visits. Results: There were no significant differences in the patient demographics and preoperative scores between the 2 groups. The mean graft diameter was 9.06 +/- 0.60 mm in the 5-strand group and 8.13 +/- 0.32 mm in the 4-strand group (P < .05). There was no statistically significant difference between groups on postoperative Lysholm, KOOS Pain, KOOS Symptoms, KOOS Activities of Daily Living, KOOS Sports, KOOS Quality of Life, and SF-36 Physical Component Summary scores. Conclusion: In primary ACL reconstruction, the 5-strand hamstring autograft achieves clinical outcomes that are comparable to those of the 4-strand hamstring autograft with a graft diameter of >= 8 mm. The 5-strand graft technique is therefore a useful means of increasing the graft diameter when faced with an undersized hamstring graft.