Inflammatory and degenerative disease in the temporomandibular joint

Sammanfattning: Temporomandibular joint (TMJ) arthroscopy is an established technique with high diagnostic accuracy regarding synovitis and degenerative changes of the articular fibrocartilage and disk. However, so far no studies have been done to correlate the macroscopic and histologic findings with each arthroscopic criterion. Therefore patients with TMJ internal derangement (ID) were investigated by arthroscopy and arthrotomy (with biopsy) and the findings were compared with observations using light microscopy. TMJ specimens obtained at autopsy were used as controls. On histological examination, inflammation was present in the majority of the patients but not in the controls. Arthroscopy revealed inflammation more accurately than did macroscopic observation at arthrotomy. Reliable arthroscopic criteria for synovitis were capillary hyperemia and synovial hyperplasia. Both correlated well with histologic signs of inflammation. Definite clinical and radiographic criteria for rheumatoid arthritis (RA) of theTMJ have been difficult to establish, and no arthroscopic data have been available. For this reason, the clinical, radiographic, arthroscopic and histologic examinations inpatients with TMJ ID or RA with TMJ signs and symptoms were compared. In RA patients joint crepitation and hard-tissue changes on the tomograms were more frequent and arthroscopic and histologic changes were more pronounced than in those with ID. Generalized osteoarthritis (GOA) is primarily a noninflammatory disease with involvement of three or more joints or groups of joints. This is the first study of the radiographic, clinical, arthroscopic, histologic and immunohistochemical changes in symptomatic TMJs in patients with GOA. The GOA patients were compared with patients having RA and TMJ symptoms. An age-matched autopsy material was used as a control for histologic and immunohistochemical examinations. On the tomograms, osteophytes, flattening of the condyle or a reduced joint space were observed more often in GOA, but erosions in the condyle were commoner in RA. Compared to RA, the radiographic findings in GOA seemed more like those in the common form of localized TMJ osteoarthritis. The frequency of muscle tenderness was the only clinical sign that differed significantly between GOA and RA (commoner in GOA). On arthroscopy, more pronounced inflammatory and degenerative changes were observed in RA patients, despite a shorter duration of symptoms. A correlation between lateral joint tenderness and pronounced synovitis was noted in RA patients. Histologic and immunohistochemical examinations showed equally high frequencies of synovial inflammation in GOA and RA, and differed clearly from those in the controls. The only histologic parameter that differed significantly between patients having GOA and those with RA was connective tissue degeneration (commoner in GOA). Immunohistochemistry (particularly PCNA = monoclonal mouse anti-proliferating cell nuclear antigen) added useful information to the histologic examination. The great similarities between the findings in GOA and in RA patients indicate that supposedly different etiopathogeneses may provoke similar tissue reactions in the joint tissues, but pronounced inflammatory changes and degeneration develop more quickly in RA.