Anterior and Posterior Arthroscopic Treatment of Primary Synovial Chondromatosis of the Ankle.

BACKGROUND

Primary synovial chondromatosis (PSC) is a progressive disorder of unknown etiology resulting in formation of multiple loose bodies. If left untreated, it may lead to degenerative changes or malignant transformation to chondrosarcoma.

METHODS

Seventeen patients who underwent combined posterior and anterior ankle arthroscopy within the same operative session and had histologically confirmed PSC were included in this retrospective study. American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot score was used to evaluate ankle function preoperatively and at a final follow-up. A 3-question survey was used to evaluate patient's satisfaction at the final follow-up.

RESULTS

In 14 patients, loose bodies were found in both compartments of the ankle, in 2 only in the anterior compartment, and in 1 only in the posterior compartment. All patients had evident signs of synovial inflammation in both compartments. The AOFAS Ankle-Hindfoot score increased from the preoperative median score of 65 (range, 29-90) to 95 (range, 65-100) at the final follow-up. Fourteen patients reported they were extremely satisfied with the outcome, 1 was moderately satisfied, and 2 were dissatisfied. No cases of recurrence of synovitis or loose body formation were noted, nor any signs of malignant transformation during the follow-up period.

CONCLUSION

We believe the risk of recurrence of PSC, which is in close relation to malignant transformation, can be minimized by performing a complete synovectomy of the ankle. Our experience and review of literature makes us believe that ankle PSC should be regarded as a whole joint disorder. Performing a combined posterior and anterior arthroscopic procedure within the same operative session should always be considered in patients with ankle PSC.

LEVEL OF EVIDENCE

Level IV, retrospective case series.