Arthroscopy of the temporomandibular joint: occurrence and location of osteoarthrosis and synovitis in a patient material.

The superior compartments of 42 temporomandibular joints of 38 patients with longstanding chronic pain and/or functional impairment were examined arthroscopically. Occurrence and location of osteoarthrosis and synovitis were investigated. Osteoarthrosis occurred in 31 joints (74%). In 17 of them more extensive changes were found. Predominant location of osteoarthrosis was the posterior slope of the eminence. The disk was less frequently affected and most commonly in the latero-central part. Synovitis occurred in 22 joints (52%) and was combined with osteoarthrosis in 17 of them. In 20 of them it was of mild and localised nature. The posterior disk attachment was affected in all of them.