Revision Anterior Cruciate Ligament Reconstruction with Over-the-top Augmentation Technique Using an Achilles Tendon Allograft for Enhanced Rotational Stability

Abstract

Abstract Purpose Revision anterior cruciate ligament (ACL) reconstruction is technically challenging due to mispositioned tunnels, bone loss, and tunnel expansion, which may compromise graft fixation or strength and result in failure. To obtain firm graft fixation and strength in one stage, we developed a new over-the-top augmentation technique using an Achilles tendon allograft in revision ACL reconstruction (OA-ACLR). This study compared OA-ACLR with single-bundle ACL reconstruction (SB-ACLR). We hypothesized that OA-ACLR would enhance the postoperative knee joint rotational stability. Methods We retrospectively analyzed 47 patients who underwent revisional OA-ACLR and 48 who underwent primary SB-ACLR. Knee instability was evaluated with the anterior drawer, Lachman, and pivot shift tests preoperatively and at the final follow-up. Side-to-side differences were compared with the non-affected side at the final follow-up. Function was evaluated using the IKDC subjective and Lysholm knee scores preoperatively and at the final follow-up. Results The groups did not differ in terms of sex, age, and BMI. Both groups significantly improved in the anterior drawer, Lachman, pivot shift tests, and IKDC and Lysholm knee scores after surgery (all p < 0.001). The OA-ACLR group showed significantly higher rotational stability in the pivot shift test than the SB-ACLR group (p = 0.017). The postoperative side-to-side difference, the IKDC and Lysholm scores showed no significant differences between the groups (p = 0.34, 0.301, 0.438). Conclusions OA-ACLR can yield a firm, stable graft reconstruction and guarantee one-stage reconstruction regardless of bony tunnel conditions. This technique can contribute to enhanced knee rotational stability and may be considered a useful alternative for revision anterior cruciate ligament reconstruction.