ACL Reconstruction With Attachment-Sparing Hamstring Autograft Results in Earlier Graft Maturation and Better Short-Term Clinical Outcome in Comparison to Free Graft: A Randomized Controlled Trial.

BACKGROUND: Attachment-sparing anterior cruciate ligament reconstruction (ACLR) is gaining acceptance over the use of free grafts because of reported early graft ligamentization in both animals and humans. However, the literature regarding clinical outcomes and the correlation of early graft healing is unclear.

HYPOTHESIS: Tibial attachment-sparing hamstring graft (AS) results in earlier graft maturation, which correlates with a better clinical outcome than a free hamstring graft (FG).

STUDY DESIGN: Randomized controlled trial; Level of evidence, 1.

METHODS: A total of 56 patients were randomly assigned to 2 groups at the commencement of the study. Of these patients, 25 (AS group) underwent ACLR using the attachment-sparing technique, while 25 patients (FG group) underwent ACLR using the free hamstring graft technique. Prospective sequential magnetic resonance imaging (MRI) evaluations were performed at 3, 6, and 9 months to document graft maturation, characteristics, orientation, and tunnel dilation. Clinical evaluation was done at 3, 6, 9, and 12 months to document Lysholm, International Knee Documentation Committee (IKDC), and Tegner scores and anterior tibial translation (ATT) by KT-2000 arthrometer, by independent observers.

RESULTS: The overall follow-up rate was 78% (19 cases and 20 controls of 25 in each group). MRI Figueroa scores demonstrated significant differences between the AS and FG groups, with the AS group showing consistently higher scores at all timelines. The earliest noticed graft maturation in the case group was at 3 months (26.3% had Figueroa score 4), compared to 6 months for the controls. In the AS group, all participants attained a Figueroa score of 5 at the final assessment, whereas only 10% of the FG group achieved that. The AS group maintained nearly the same graft diameters, but the FG group showed increased diameter (graft swelling) at all follow-up time points. A significant increase in tibial tunnel diameter over time was observed in both groups, with a greater increase in the AS group. A significant improvement was observed in Lysholm score, IKDC score, and ATT in both groups.

CONCLUSION: Tibial attachment-sparing hamstring grafts result in earlier and complete graft maturation on MRI as compared to free hamstring grafts for ACLR.

REGISTRATION: Clinical Trials Registry - India (CTRI/2022/10/046620).