Temporomandibular joint: diagnosis of medial and lateral disk displacement with anteroposterior arthrography. Correlation with cryosections.

The purpose of this investigation was to determine whether it is possible to diagnose medial and lateral disk displacements by single-contrast lower-compartment arthrography with an anteroposterior projection. Contrast medium was injected into the lower joint space of 29 fresh temporomandibular joint autopsy specimens. Anteroposterior arthrograms and anteroposterior arthrotomograms were obtained. Enlargement of the medial or lateral recess of the lower joint space was considered an arthrographic indication of medial or lateral displacement of the disk. After arthrography the joints were deep frozen and cryosectioned in the coronal plane. Imaging findings were correlated to observations in the cryosections in a blind fashion. The anteroposterior arthrograms were 48% accurate in determining the position of the disk in the coronal plane. The anteroposterior arthrotomograms were 59% accurate. It was concluded that anteroposterior lower joint space arthrography as well as arthrotomography is not reliable for diagnosis of medial or lateral disk displacement.