Synovial chondromatosis masquerading as a para-meniscal cyst of the knee

Synovial chondromatosis and parameniscal cysts are well documented pathologies around the knee joint. We present an unusual presentation of synovial chondromatosis masquerading as a parameniscal cyst of the knee. The patient was an 82-year old gentleman seen in our knee clinic with painful swelling over medial aspect of the right knee, no history of injury and with symptoms of a locked knee. Clinico-radiological features were suggestive of a binary pathology of a meniscal tear and multi-locular cyst of the knee. An arthroscopic assisted open excision of the cystic lesion allowed clinical recovery with histological confirmation of benign synovial chondromatosis. We highlight the challenges in our case with the overlap of diagnostic features of both synovial and meniscal pathology with surgical management of this patient.