Temporomandibular joint (TMJ) inflammation may occur as a result of an inflammatory arthropathy or secondary to TMJ dysfunction. Since the TMJ is a synovial joint, it is susceptible to inflammatory arthropathies that affect other joints.
- rheumatoid arthritis (RA) : is by far the most common
- ankylosing spondylitis
- calcium pyrophosphate deposition disease (CPPD)
- psoriatic arthritis
- systemic lupus erythematosus (SLE)
It is important to realise that active periods of TMJ dysfunction may also produce inflammatory signs.
Imaging of choice is MRI, which unfortunately is unable to distinguish between them, as all share the same spectrum of imaging findings.
- synovitis and pannus formation (distinguished from TMJ effusion by administration of contrast)
- soft tissue swelling and oedema (best seen on STIR): this is most pronounced in the retrodiscal zone
- bone marrow oedema
- marginal erosions
- joint space narrowing
Eventually, secondary degenerative osteoarthritic changes of develop (see TMJ OA), with joint space narrowing, cortical erosions, condylar flattening and marginal osteophytes
- 1. Oliver J. Sommer, Felix Aigner, Ansgar Rudisch, Hannes Gruber, Helga Fritsch, Werner Millesi, and Michael Stiskal "Cross-sectional and Functional Imaging of the Temporomandibular Joint: Radiology, Pathology, and Basic Biomechanics of the Jaw" RadioGraphics 2003 23: e14; published online as 10.1148/rg.e14
- 2. Xavier Tomas, Jaume Pomes, Juan Berenguer, Llorenç Quinto, Carlos Nicolau, Josep Maria Mercader, and Vicente Castro "MR Imaging of Temporomandibular Joint Dysfunction: A Pictorial Review" RadioGraphics 2006 26: 765-781.