Preservation of the Anterior Cruciate Ligament: A Treatment Algorithm Based on Tear Location and Tissue Quality

The gold standard of anterior cruciate ligament (ACL) injuries is currently single-bundle autograft reconstruction. However, many disadvantages of reconstructive surgery exist, such as: anterior knee pain, muscle atrophy, and loss of range of motion. In addition, native kinematics are not restored, and osteoarthritis is not prevented. Finally, revision surgery, if necessary, can be problematic due to tunnel widening, tunnel malpositioning, and preexisting hardware. Ligament preservation includes preservation of native tissues in order to optimize the biologic aspects, while decreasing the invasive nature of reconstructive surgery. In the 1970s and 1980s, ACL preservation via open primary repair was widely performed, but the technique was abandoned due to unpredictable results. Unfortunately, the influence of both tear location and tissue quality on primary repair outcomes was not adequately recognized. Augmented repair, essentially a combination of primary repair and reconstruction, was then performed in the 1980s and early 1990s. Despite excellent results, for multiple reasons the surgical community moved on to ACL reconstruction, which was adapted as the gold standard. With the current knowledge of the role of tear location and tissue quality on outcomes of ACL preservation, in combination with modern advances of magnetic resonance imaging, arthroscopic technology, and the benefits of early rehabilitation, there is likely a role for ACL preservation today. In this article, we (I) discuss the history of ACL preservation, (II) discuss how modern advances alter the risk-benefit ratio for ACL preservation, and (III) propose a treatment algorithm for ACL injuries that is based on tear location and tissue quality.