ACL and hidden meniscus lesions

ACL tears are frequently associated with meniscal lesions. Despite improvements in meniscal repair techniques, failure rates remain significant, especially for the posterior horn of the medial meniscus (MM). Therefore, we recommend that a systematic arthroscopic exploration of the posterior horn of the MM be performed. The first step of the arthroscopic exploration requires routine anterior visualization via a standard anterolateral portal. In the second step, the posterior horn of the MM is visualized posteriorly. For this, the scope is positioned deep in the notch underneath the posterior cruciate ligament (PCL) via the anterolateral portal. In the third step, the posterior horn is probed through an additional posteromedial portal. In 17 % of posterior horn MM tears, a tear was discovered through minimal debridement of a superficial soft-tissue layer with a motorized shaver. This type of lesion was called a “hidden lesion.�? Suture repairs of these ramp or hidden lesions of the posterior horn of the MM were performed with the use of a suture hook, which was introduced through the posteromedial portal. These meniscal tears have good healing potential with a low rate of revision at an average of 2-year follow-up. It seems to be a promising technique because it allows the placement of vertically oriented sutures with good tissue approximation. The additional posteromedial portal allows for better visualization, easier access, and sufficient debridement prior to repair. In previous work it was demonstrated that repairing these lesions at the time of ACL reconstruction is very important in order to restore knee biomechanics and minimize stress on the ACL graft.