Guidelines for diagnosis and management of disorders involving the temporomandibular joint and related musculoskeletal structures.

The following document was developed as a consensus statement by members of a multidisciplinary organization of clinicians who have extensive experience in the diagnosis and treatment of patients with temporomandibular joint (TMJ) arthropathy and associated musculoskeletal disorders. These guidelines represent current accepted theory and practice among the membership. II. BACKGROUND Temporomandibular Joint The temporomandibular joint differs from other joints of the body primarily by its sliding function and having joint surfaces and a disc of fibrocartilage. The disc is attached to the condyle by ligaments that permit rotation on the condyle during translational jaw movements. A highly vascular attachment with elastic fibers secures the posterior border of the disc and a muscle (lateral pterygoid) the anterior border. The sides of the disc are attached to the medial and lateral poles of the condyle. During jaw movements the condyle and disc slide in the temporal fossa. Without this sliding movement, sideways movement of the jaw during chewing, and especially wide opening, would not be possible. The disc is believed to have several roles, such as, cushioning and distributing joint loads, promoting joint stability during chewing, facilitating lubrication and nourishment of the joint surfaces, preventing gross degenerative changes in the condyle and fossa, and promoting normal growth of the mandible (1). Although some properties of this joint are unique, the disc and joint basically behave similarly to other load-bearing appendicular joints with discs or menisci. Classification Temporomandibular disorders (TMD) is a collective term embracing all the problems relating to the TMJ and related musculoskeletal structures. One classification of TMD disorders is listed in Table I. These guidelines, however, will focus on the clinical and pathological condition of disc displacement, which is an internal derangement (ID), and the usual coexisting osteoarthritis (OA), also known as osteoarthrosis or degenerative joint disease (DJD) (2). The reason for this focus is that ID/OA is considered to be the most common cause of serious TMJ pain and dysfunction and therefore the most likely to be treated surgically. Prevalence Disc displacement was not found in 30 infants or young children imaged by magnetic resonance (3). However, asymptomatic disc displacement was documented in 8% of juveniles with a mean age of 11 years (4) and about 30% of adult volunteers (5-9). In symptomatic patients, ID is present 80-90% of the time (5-11). Moreover, patients referred for surgical consultation because of symptoms, seem to have an even higher incidence of …