Diffuse Pigmented Villonodular Synovitis Around the Ankle

Background: Pigmented villonodular synovitis (PVNS) is a rare disorder around the ankle joint. The optimal treatment for diffuse-type PVNS is still controversial because of the high incidence of recurrence. We present the clinical features of our patients and review the current diagnostic and treatment modalities. Methods: Five patients with PVNS located around the ankle were surgically treated. In three patients, diffuse PVNS arose from the ankle joint, and in the other two it arose from the calcaneocuboid and intercuneiform joints. The average follow-up time after surgery was 2.9 years (range, 2-4.6 years). Results: The average time between onset of pain and diagnosis of PVNS was 6.4 years (range, 4-10 years). Arthrotomic tumor resection was performed in all of the patients. In the three patients with ankle joint PVNS, both medial and lateral approaches were used. One patient experienced mild infection at the surgical site, but this healed conservatively. No tumor recurrences had occurred after minimum follow-up of 2 years, although mild pain persisted in the three patients with ankle PVNS. Conclusions: Diagnosis of diffuse PVNS is frequently delayed due to vague symptoms and variable growth patterns. Orthopedic clinicians should be aware of the existence of this lesion, and it should be suspected in patients with persistent ankle swelling. To prevent tumor recurrence, accurate evaluation of tumor location and careful operative planning are mandatory. A combined surgical approach involving medial and lateral incision is necessary to expose the entire joint cavity.