Effect of Cross-sectional Area of the Hamstring Tendon Autograft on Failure Rate or Clinical Outcomes After Double-Bundle ACL Reconstruction: Tendon Autograft

Abstract

Background: In previous studies examining the relationship between graft size and failure rate after anterior cruciate ligament reconstruction (ACLR), graft size was determined as diameter of the bone tunnel, and graft failure was defined as revision surgery. Consequently, the correlation between graft size and postoperative recurrent instability could not be assessed. Purpose: (1) To intraoperatively measure the cross-sectional area (CSA) of the hamstring tendon (HT) autograft and compare the CSA of the autograft with the bone tunnel and (2) to assess the effect of the graft CSA on postoperative graft failure among patients who underwent double-bundle ACLR. Study Design: Case-control study; Level of evidence, 3. Methods: The study included 129 patients who underwent double-bundle ACLR using an HT autograft (mean ± SD age, 16.7 ± 1.7 years; all with a Tegner activity level ≥6). All patients had a minimum follow-up of 2 years. During surgery, the graft CSA was measured using an area micrometer, combining the anteromedial (AM) and posterolateral (PL) grafts. The total area of the bone tunnel was defined as the combined CSAs of the AM and PL tunnels as calculated by the diameter of the drill. The relationship between the CSAs of the combined HT graft and the bone tunnel was statistically compared, as was the relationship between graft CSAs and graft failure, defined as reinjury, recurrent instability manifested as quantitative laxity measurement, or revision ACLR. Results: The CSAs of the midsubstance of the combined AM and PL graft significantly correlated with those of the bone tunnels (femoral side, R 2 = 0.334, P < .0001; tibial side, R 2 = 0.421, P < .0001). As for the relationship between the graft CSA and ACLR failure, there was no significant difference in the graft CSAs between the groups with and without graft failure in any of the failure criteria ( P = .188). Conclusion: The graft CSA was not a predictor of early failure after double-bundle ACLR using an HT autograft in this patient population.