Temporomandibular joint: variation of normal arthrographic anatomy

The arthrograms of 34 individuals with asymptomatic, clinically and arthrographically normal temporomandibular joints were analyzed. The results showed a substantial variation of the dimensions and configuration of the joint compartments. Thus the anterior recess of the lower joint compartment was small in 15 joints (44%), medium-size in 16 joints (47%), and large in three joints (9%). The upper margin of this recess was flat or convex in 24 joints (71%) and concave in 10 joints (29%). These observations contradict previous assumptions about a strict association between the configuration and dimension of the anterior recess of the lower joint compartment and the position of the disk. It was concluded that dimension and configuration of the joint compartments should not be used as the only criteria for diagnosis of the position of the disk.