Ramp lesions. In Knee arthroscopy: An up-to-date guide. (Book Chapter)

Ramp lesions to the posterior horn of the medial meniscus have recently received increased attention due to their high prevalence in patients undergoing an anterior cruciate ligament reconstruction. The diagnosis of these lesions is rarely possible with preoperative imaging and quite limited with routine anterior arthroscopic inspection of the knee joint. Visual inspection of the posteromedial compartment of the knee joint should thus systematically be carried out via a trans-notch view and meniscocapsular structures directly probed with a needle or visualized via a posteromedial portal. While the clinical impact of ramp lesions is not yet well established, recent biomechanical studies have shown increased anteroposterior and rotational laxities when a ramp lesion is present. The latter may thus be a cause for postoperative persistent laxity potentially leading to the failure of ACL reconstructions. To date, it remains unclear whether all ramp lesions should be repaired as only a few publications report long-term outcomes after ramp lesion repair. This article provides an overview of the current knowledge on ramp lesions including their diagnosis, classification, biomechanical relevance as well as treatment and outcomes.