The independent variables (predictors) were the following: the shape of mandibular condyle, flattening of articular eminence, erosion of articular eminence, erosion of mandibular condyle, erosion of articular fossa, mandibular subchondral cyst, osteophytosis, mandibular subchondral sclerosis, and position of mandibular condyle.
Upon studying the independent variables for the presence of clinical manifestations, the erosions of the articular eminence and mandibular condyle were the only radiological predictors of pain on palpation (tenderness).
30) In another study, an abnormal condyle was observed in 32% of RA patients, flattened articular eminence in 27%, flattened articular disks in 17%, and restricted condylar motion in 9%.
Major components of the TMJ include the mandibular condyle, the articular disc, the glenoid fossa, and the articular eminence of the temporal bone (Figure 1).
During translation, the disc and condyle move under the articular eminence; the intermediate zone of the disc remains interposed between the articular eminence and mandibular condyle.
Uncommonly, an open lock can occur when the mandibular condyle is unable to translate back into the glenoid fossa, whether due to posteriorly displaced disc material or due to the articular eminence (Figure 4).
The authors use proton-density imaging for our sagittal oblique static evaluation of the joint, as the disc is well seen as a hypointense biconcave structure between the condyle and articular eminence.
Given some degree of subjectivity of the clock-face interpretation with the size of the condyle and the possibly difficult visualization of the margin of the posterior band (particularly in the degenerated disc), some advocate evaluating the position of the intermediate zone, looking for its interposition between the articular eminence and mandibular condyle.
As the jaw opens, the disk remains between the condyle and the articular eminence as the condyle translates anteriorly.
5) Destruction of the condyle and articular eminence are typical findings, and marrow signal abnormalities may reflect edema or, occasionally, subchondral sclerosis.
An anteriorly dislocated mandibular condyle is visualized anterior and superior to the articular eminence (Figure 9).
As regards the radiographic comment, we agree that superimposition of the articular eminences
overlying the sphenoid is a reality.