The posterior medial meniscotibial ligament (posterior medial coronary ligament) connects the posterior horn of the medial meniscus to the posteromedial tibial plateau margin, functioning as the posterior tethering mechanism of the medial meniscus. It is thicker and more distinct than the anterior medial coronary ligament, and its firm attachment limits the posterior excursion of the medial meniscus to approximately 5 mm during full flexion.
Anchors the posterior horn of the medial meniscus to the posteromedial tibial plateau; limits posterior horn displacement during knee flexion; contributes to medial compartment stability by preventing posterior horn extrusion.
The posterior medial coronary ligament is disrupted in peripheral medial meniscal tears and in posteromedial corner injuries. When the posterior coronary ligament fails alongside MCL injury, the medial meniscus loses its posterior tibial tether and can migrate anteriorly during pivot-shift manoeuvres, causing the snap felt during anteromedial rotatory instability. Posterior horn medial meniscus repair through the posteromedial arthroscopic portal requires identification and preservation of the posterior coronary attachment during the approach.
Combined medial knee injury disrupting the superficial MCL and posterior coronary ligament produces medial compartment laxity with the medial meniscus losing its posterior tibial attachment, allowing anterior meniscal migration during pivot-shift; MRI demonstrates medial coronary ligament signal abnormality below the medial joint line adjacent to the posterior horn.
