The clinical predictability of internal derangements of the temporomandibular joint.

The value of clinical parameters as predictors of the arthrographic findings in patients with temporomandibular joint (TMJ) pain and dysfunction was examined in this study. We developed a series of simplified clinical prediction rules based on previous studies correlating clinical signs and symptoms with arthrographic diagnosis of the condition of the TMJ meniscus. One hundred eighty-six patients with signs and symptoms of TMJ dysfunction were clinically examined before TMJ arthrography. Arthrograms were performed on 246 joints (126 unilateral, 60 bilateral). The rules predicted 91 of the 246 joints to be normal when actually 59 were shown to be normal arthrographically. The rules slightly underpredicted those patients with positive arthrographic findings for internal derangements. Although there were some individual variations in the predictability of unilateral versus bilateral arthrograms (patients), there was very little overall difference, 58% and 60%, respectively. This study confirms previous suggestions that clinical findings alone are not consistently accurate in diagnosing the exact type of TMJ internal derangements depicted by arthrographic criteria.