EXTRAARTICULAR PIGMENTED VILLONODULAR SYNOVITIS OF THE TEMPOROMANDIBULAR-JOINT

Pigmented villonodular synovitis, a benign but locally destructive fib rohistiocytic proliferative lesion involving tendon sheaths, bursae an d diarthrodial joints, is distinctly rare in the temporomandibular joi nt. We report one such case occurring in a 42-year-old housewife who p resented with a progressively enlarging right zygomatic mass for six m onths. Can exploration, an orange-brown firm mass, 5 x 3 x 2 fm, was s een adherent to the lateral aspect of the capsule of the right temporo mandibular joint, and eroding into the inferior aspect of the right te mporal bone and part of the mandibular condyle. The mass was completel y excised, Pathological examination showed features typical of those o f pigmented villonodular synovitis and the lesion was entirely extra-a rticular in location. The patient remained well with no evidence of lo cal recurrence two years after operation. Review of the literature and careful analysis of the clinicopathological features showed that the vast majority of the reported cases of pigmented villonodular synoviti s of the temporomandibular joint belonged to the extra-articular varia nt, which is associated with a more aggressive local infiltrative beha viour and higher rate of local recurrence than the localized type. The recommended treatment for this condition is therefore wide local exci sion, aiming to remove the lesion as completely as possible without pr oducing severe disability for the patient.