Validity and Reliability of Joint Vibration Analysis in TMJ Assessment

Objectives: Joint noise has long been considered one of the defining criteria for intracapsular disorders of the TMJ despite issues with reliability in detection and variability across patients. This study investigates the use of an alternative technique to analyze joint noise, Joint Vibration Analysis (JVA), and it’s predictive validity to scores on the Research Diagnostic Criteria (RDC) and as well as reliability with multiple examiners.

Methods: 51 consecutive patients who sought treatment in a private practice for joint pain and dysfunction were sequentially examined with the RDC and JVA.  The diagnostic categories evaluated were normal joint, disc displacement with reduction, disc displacement without reduction, clicking, lateral clicking, degenerative conditions, and overall intracapsular diagnosis.  Three examiners interpreted JVA results and the rate of agreement was evaluated.

Results: Levels of agreement demonstrated poor kappa values for all categories except disc displacement with reduction at 0.413.  Predictive ability to the RDC was only significant for disc displacement with reduction at p=0.003 with a sensitivity and specificity of 76% and 65% respectively.  The overall percentage agreement between RDC and JVA for detection of the different conditions was within 10% for the categories of degenerative conditions, disc displacement with reduction, disc displacement without reduction, and intracapsular diagnosis.

Conclusions: The results indicate that interpretation of JVA results have a significant subjective component that can lead to inconsistent classification of intracapsular pathology in addition to a lack of validity as evidenced by an absence of a predictive relationship to the RDC.