To evaluate clinical, radiological and histological characteristics as well as outcome of pigmented villonodular synovitis (PVNS) in 14 patients.This retrospective study examined data from 14 cases of pathologically-confirmed PVNS over a 10-year period (1990-1999).All 14 cases (9 women and 5 men) of PVNS involved the knee. Mean age at diagnosis was 32.7 years. The principal functional signs were mechanical pain and disability. All patients had radiographs (normal for 8 patients); 3 had arthrography, which found diffuse cyst formations, 2 had MRI, which showed images characteristic of PVNS, and 4 had arthroscopy. All patients underwent complete surgical excision, and 4 also had osmic acid synoviorthesis. Recurrence occurred in 4 patients, within 10 months on average.MRI and arthroscopy improve the early management of pigmented villonodular synovitis.