Pigmented villonodular synovitis of the knee: a series of 22 cases

Purpose of the study The authors report their experience about 22 cases of pigmented villonodula r synovitis of the knee observed between 1970 and 1997, The authors studied the results of treatments according to localization, evolutionnary stage a nd condition of an early diagnosis. Material and methods Among thirty three cases of pigmented villonodular synovitis treated during the same period the knee was involved in twenty two cases. Diagnosis was d one or highly suspected in 13 cases because of significant symptoms (iterat ive hemarthrosis, bony gap in both articular components of the joint) or by MRI, The biopsy performed in each case allowed histological assessment in 22 patients. Surgical treatment was achieved in 19 patients, Three knees we re not operated (two patients refused; one had a synoviorthesis) the treatm ent was a synovectomy alone for fifteen patients; four patients, needed a k nee prosthesis, because of important degenerative joint disease. Results Fourteen patients, with a mean follow-up of five years were reviewed. Four had a recurrence which appeared between three and eight years after subtota l synovectomy for diffuse synovitis, There were no recurrence after arthrop lastic treatment and in localized lesions, Discussion Pigmented villonodular synovitis should be treated as soon as possible but its different clinical features make diagnosis sometimes difficult. Because of an agressive tendency of the disease which finds expression in extensiv e lesions in joint and bone, and early diagnosis allowed by MRI could make the prognosis more favourable, Conclusion Surgical synovectomy is the usual treatment. In evolved stages arthroplasti es are performed, Localized lesions and recurrences should need arthroscopi c treatment.