Ganglion cysts of the anterior cruciate ligament: a series of 15 cases.

PURPOSE To increase awareness of the presence of ganglion cysts of the anterior cruciate ligament and to consider this diagnosis in any knee that has lost range of motion (ROM) in the absence of osteoarthritis. TYPE OF STUDY Case series. METHODS We present a series of 15 cases recorded over a period of 5 years illustrating the clinical presentation and additional pathology seen at arthroscopy. International Knee Documentation Committee scores were calculated at the recent follow-up to establish outcome of the surgery. RESULTS The cysts occurred predominantly in men with the most common presenting complaint being decreased ROM and pain. Overall, results were excellent with no recurrence of symptoms at a mean 36-month follow-up, but outcome does appear to be associated with other pathology present. ROM was improved with arthroscopic excision of the cyst in all cases that were impaired. CONCLUSIONS Although rare, ganglion cysts related to the cruciate ligaments of the knee should be considered in the differential diagnosis of a painful knee especially when associated with a decreased ROM and no evidence of osteoarthritis on radiographs. Other pathology can often be present, which may affect the overall outcome, but arthroscopic debridement of the ganglion cyst should be considered the treatment of choice in order to reliably restore active ROM. LEVEL OF EVIDENCE Level IV, Case Series.