Localized nodular pigmented villonodular synovitis of the upper ankle joint--diagnosis and treatment.

This paper introduces a case of local pigmented villonodular synovits (PVNS) of the upper ankle joint in a 37-year old patient. PVNS is a neoplasia of the synovial membrane. Two different entities of PVNS are known: generalized diffuse and local nodular. They differ in their degree of destruction and growth configuration, which is crucial for prognosis and operative treatment. The most common location of the local nodular form is the knee joint, followed by the finger joints. Occurrence in the ankle joint is not common but should be considered if clinical findings are present. MRI is the method of choice for diagnosis and assessment of the bone situation. Treatment consists of radical excision of the neoplasia. Radiosynoviorthesis is recommended as a post-operative treatment to increase the probability of a total removal of persisting PVNS cells. The rate of recurrence seems to be between 8 and 46%.