A Single Bundle Anterior Cruciate Ligament Reconstruction (ACL-R) Using Hamstring Tendon Autograft and Tibialis Anterior Tendon Allograft: A Comparative Study

The main purpose of this study was to compare the clinical outcomes of patients undergoing a single bundle anterior cruciate ligament reconstruction (ACL-R) of using quadrupled hamstring (4HT) autografts and two-strand tibialis anterior (2TA) allografts, and to find out the rate of graft failure and possible causes. We hypothesized that there would be no difference in the clinical outcome, and graft failure would be associated with the use of small sized allograft in young active males with high demand of sports activities. We retrospectively evaluated 222 patients (male, n=167, female, n=55) undergoing ACL-R between January 2010 and July 2014. Of 222 patients, 115 were included in the 4HT autograft group and 107 patients in the 2TA allograft group. Inclusion criteria were primary unilateral ACL-R with a minor MCL (<grade II) injury with or without meniscus tear and had at least 2.5 years of follow-up. Subjective evaluation was performed using Tegner-Lysholm score, modified Cincinnati knee score, and IKDC knee form. Anteroposterior laxity was assessed using ADT and Lachman test whereas rotational laxity was assessed using pivot shift test. Similarly, functional assessment was performed using range of motion (ROM), Daniel’s one-leg hop test, and overall IKDC score. Clinical outcomes were satisfactory and comparable in both groups with no statistically significant difference in all the respective parameters. No statistically significant difference was observed in graft re-rupture rate. However, most graft failures occurred in young active males with high demand of sports activities, graft size smaller than 8 mm, and use of allograft. An autograft with at least 8 mm diameter should be considered in a young active male with high demand of sports activities to avoid graft failure.