Pigmented villonodular synovitis of the wrist with penetration into bone.

Invasion and erosion of bone in nodular synovitis (histiocytic xanthomatous granuloma, xanthoma, giant-cell tumour, benign synovioma) are found fairly frequently in circumscribed lesions of the tendon sheaths of hands and feet. Fletcher and Horn (1951) in particular called attention to this. Bone involvement in diffuse forms, namely “ pigmented villonodular synovitis, bursitis and tenosynovitis “ (Jaffe, Lichtenstein and Sutro 1941) are much less common. The clinical and pathological features of this condition are well known. Mandl (1928) reported a similar condition under the name of “ haemorrhagic chronic villous synovitis “: at a second operation abundant blood pigment and extensive xanthomatous areas were found. One of us (F. S.) reported another patient, also operated upon by Mandl, in 1937, under the same denomination (Schajowicz 1937). In 1963 Schajowicz and Slullitel presented before the Argentine Orthopaedic Society a case of pigmented villonodular synovitis affecting the shoulder with invasion of the humerus and scapula. Reviewing the literature and material filed with the Latin-American Register of Bone Pathology, they found fifty-two cases with invasion of one or more bones adjacent to the affected joint, including twelve cases studied in the laboratory of the Register. The hip, ankle and knee were the joints most commonly affected. On only two occasions did the condition affect the wrist (Lewis 1955) and carpus (Smith and Pugh 1962). Following our paper, Chung and Janes (1965) reported four cases of affection of the hip. Including the case mentioned in this report we have observed six new cases of bone invasion among twenty-seven cases of pigmented villonodular synovitis studied in our laboratory. For this reason we do not believe that this complication of pigmented villonodular synovitis is so rare as appears from the few cases published. The case reported here is of special interest because of the severity of the invasion of the lower end of the radius and because of the size of the lesion. These features raised the possibility that the lesion might be a giant-cell tumour of bone with extensive invasion of the neighbouring soft tissues and bones and perhaps with malignant change.