Temporomandibular joint disorder (TMD) refers to limited motion of the temporomandibular joint (TMJ) which joins the temporal bone and the jaw. This is sometimes called temporomandibular joint syndrome, or TMJ syndrome. It may result in difficulty in opening and closing the mouth, in side-to-side movement of the jaw, and chewing.

Limited motion of the TMJ can be caused by numerous abnormalities both within and outside of the joint itself. The most common limitation results from painful disorders of the muscles that move the mandible, particularly muscle hyperactivity. Restrictive conditions within the joint include arthritis, scarring, bony fusion or disk displacement. Restrictive conditions outside the joint include tissue changes from trauma, previous surgery, infection or radiation, as well as tumors and abnormal bone growth.

Patients with limitations of TMJ motion may report difficulty eating normal foods due to restricted opening, pain in or around the TMJ area, and sometimes joint noises, including clicking, popping or grating sounds. Symptoms may be severe, and patients may report significant disturbances to sleep and appetite, as well as other lifestyle changes. Signs include: limited jaw opening, shifting to one side on jaw opening, limitations in side-to-side movement, pain on jaw movement, or joint noises. Pain may be found on palpation of the TMJ area or the associated muscle and soft tissues.

Physical examination, radiographic studies (plain x-rays, computed tomography (CT) scan or magnetic resonance imaging (MRI), arthrography, arthroscopy), and psychological evaluation are used to demonstrate abnormalities.

Treatment is focused on the underlying condition. Generally, there is a course of nonsurgical treatment that may include: diet modification, applied heat, medications, TMJ irrigation or medication injection, physical therapy, behavioral modification, psychological evaluation and counseling, and dental splint therapy. Surgery is performed when conditions exist that can be remedied by such procedures.

Some limitations of TMJ motion are chronic and do not completely reverse with therapy. There can be persistent restriction in jaw opening, persistent pain, including severe pain, and lifestyle modification.

• Prior to September 10, 2017, this diagnostic code referred to temporomandibular articulation, limited motion of. This condition has also been referred to as TMJ.

• Ratings for limited interincisal movement shall not be combined with ratings for limited lateral excursion.

• For VA compensation purposes, the normal maximum unassisted range of vertical jaw opening is from 35 to 50 mm.

• For VA compensation purposes, mechanically altered foods are defined as altered by blending, chopping, grinding or mashing so that they are easy to chew and swallow. There are four levels of mechanically altered foods: full liquid, puree, soft, and semisolid foods. To warrant elevation based on mechanically altered foods, the use of texture-modified diets must be recorded or verified by a physician

• For VA compensation purposes, diagnostic imaging studies include, but are not limited to, conventional radiography (X-ray), computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), radionuclide bone scanning, or ultrasonography

• Separately evaluate loss of vocal articulation, loss of smell, loss of taste, neurological impairment, respiratory dysfunction, and other impairments under the appropriate diagnostic code and combine under 38 CFR 4.25 for each separately rated condition