Medial meniscal cyst as a cause of painful erosion of the tibial plateau.

Medial cysts are rarely encountered as a cause of bone erosion. It is thought meniscal cysts are present in up to 22 % of meniscal tear operations. MRI is the gold standard for visualisation of meniscal cysts. Decompression is often guided by careful study of the pre-operative MRI scans in multiple planes. This is the first case report demonstrating erosion of the medial tibial plateau due to an incarcerated meniscal cyst highlighting the potential for bone damage if left untreated. Level of evidence IV.