Case report. An unusual cause of a patient presenting with an acutely locked knee: multiple benign fat pad cysts.

Benign ganglion (synovial) cysts within the knee are uncommon and especially so when located in the infrapatellar fad pad. They cause many non-specific symptoms but usually present as a swelling. We report the case of a young gentleman with multiple benign synovial cysts within the fat pad causing a locked knee, which was treated with arthroscopically assisted open excision. We can find no previous reports of isolated multiple fat pad cysts causing acute locking of the knee.