Case report 590: Diffuse pigmented villonodular synovitis with a cartilaginous component.

The authors present the case of a patient 54 years of age who developed well-defined osteolysis in the distal end of the humerus, with a slight radiodensity in the soft tissue. The radionuclide scintigram and above all the CT, were useful in defining the characteristics and expansion of the mass more precisely. Surgical intervention and histological examination demonstrated a seemingly unique case of PVNS of the elbow with diffuse cartilaginous components and erosion of the distal end of the humerus. The pathological findings in this unusual case, actually suggested the possibility of an intermediate form of PVNS associated with synovial chondromatosis.