Preservation of hamstring tibial insertion in anterior cruciate ligament reconstruction: a review of the current literature.

Hamstring graft (HG) used in anterior cruciate ligament (ACL) reconstruction undergoes a biological modification process called "ligamentization" in the early postoperative period that proceeds through three different phases: an early graft-healing phase with central graft necrosis, a phase of proliferation, and finally, a ligamentization phase toward the properties of the intact ACL. The fastening of this process could result in more aggressive rehabilitation protocols as well as faster sport resumption. A recent literature supports the preservation of HG tibial attachment in order to enhance "ligamentization" process. Aim of this literature review is to describe all the techniques described that spare HG tibial insertion and the obtained results in order to evaluate evidence that would substantiate the maintenance of HG tibial insertion in ACL reconstruction. A search was performed using the following keywords "ACL reconstruction" in combination with "hamstrings," "hamstrings insertion," "tibial insertion," "ligamentization," and "over the top"; 18 articles were found to be relevant. Among these, eight randomized clinical trials (RCTs) were found. The RCT analyzed presented a high number of biases regarding the analyzed topic, thus making impossible to draw definitive evidences to validate HG tibial insertion sparing in ACL reconstruction. Despite the satisfactory results in many clinical series and the promising results in anatomic and animal studies, well-designed prospective clinical trials with large cohort of patients associated with MRI evaluation are mandatory to assess the beneficial effects of HG attachment preservation in ACL reconstruction.