Interpretation and treatment of computed tomographic abnormalities of the temporomandibular joint

The equine TMJ is a complex diarthrodial, load bearing, synovial joint that has non-communicating dorsal (larger) and ventral (smaller) compartments divided by a fibrocartilaginous intra-articular disc. The articular surfaces of the TMJ are covered with fibrocartilage as opposed to the hyaline cartilage of other articular surfaces [1]. Imaging of the joint is difficult with conventional modalities given the superimposition of surrounding structures. CT is readily available, affordable, fast, carries minimal risk as a standing procedure and enables the most comprehensive anatomical evaluation of the TMJ. It is highly sensitive and specific [2]. CT allows excellent visualisation of the articulation between the mandibular condyle and the base of the zygomatic process of the temporal bone composed of the articular tubercle, mandibular fossa and retroarticular process of the temporal bone [2]. CT does not permit evaluation of the soft tissues of the TMJ. Ultrasound of the lateral aspect of the joint may be complimentary in evaluation of the meniscus and the joint capsule as well as assessment of the degree of joint effusion associated with disease. Transverse and sagittal CT images provide most information relating to articular surface and position of the condyle, mandibular fossa and peri-articular process ...