Temporomandibular joint "open lock" versus condylar dislocation: signs and symptoms, imaging, treatment, and pathogenesis.

PURPOSE: In the temporomandibular joint (TMJ) "open-lock" condition the condyle is entrapped in front of the lagging disc and cannot slide back under the fossa. The aim of this retrospective study was to describe the signs and symptoms and imaging of TMJ "open lock" versus condylar dislocation and clarify its pathogenesis. The study stresses the efficacy of arthrocentesis in restoring the functional capacity of the joint, while obviating the need for surgical intervention.

PATIENTS AND

METHODS

The study included 5 patients (3 females and 2 males; ages ranging from 11 to 26 years) presenting 6 open-lock joints that did not respond to conservative treatment. The TMJs postarthrocentesis status in 5 joints (follow-up period, 6 to 32 months) was determined by patient self-assessment and clinical examination.

RESULTS

Five TMJs had recurrent open lock and were treated by arthrocentesis. They reacted favorably to the treatment and the open-lock events were eliminated. The first case was apparently misdiagnosed as condylar dislocation, and unnecessary surgical intervention was performed.

CONCLUSIONS

Arthrocentesis is a safe and rapid procedure that prevents recurrence of open-lock conditions. This disorder should be distinguished from recurrent condylar dislocation, which requires surgical intervention.