OMS TMJ Flashcards
(30 cards)
Name the two descriptive categories of TMJ disorders. Which is most common?
Extra-articular disorders and intra-articular disorders. Extra-articular disorders are far more common.
Contrast the findings in TMJ osteoarthritis and TMJ synovitis.
Osteoarthritis is a degenerative disease in the TMJ, as it is in
other joints in the body. It is caused by a loss of articulating tissues and can be described as a mechanical,
noninflammatory disease with bone-on-bone contact. By
contrast, TMJ synovitis is definable by its inflammatory nature. Inflammatory mediators may accumulate secondary to trauma, disk malfunction, or parafunctional habits.
What is the best imaging modality for the TMJ?
Disk displacement and internal derangement of the TMJ are
best imaged using MRI. Bony diseases such as ankylosis or degenerative joint disease are best evaluated using CT.
Panorex may be used as to screen for fracture, condylar
resorption, or large pathology.
How is TMJ internal derangement classified?
The Wilkes classification
● Stage 1: Asymptomatic, painless clicking; mild disk displacement with reduction
● Stage 2: Occasional painful clicking or locking; mild disk
displacement and deformity
● Stage 3: Joint pain with functional changes (limited
opening); nonreducing disk with deformity
● Stage 4: Chronic pain and functional deficit, degenerative
osseous changes, and disk deformity
● Stage 5: End stage with crepitus, degenerative joint
disease (DJD), and disk perforation or loss
Name the two categories of TMJ disk displacement.
● Disk displacement with reduction (often heard as popping or clicking)
● Disk displacement without reduction (usually no associated noise)
Note: Often, displacement with reduction leads to dis-
placement without reduction, which limits range of motion.
This may be reversed with conservative therapy or with
arthrocentesis or arthroscopy.
In the case of anterior disk displacement with or without reduction, what are the indications for
intervention?
Pain, impaired mobility (especially acute closed lock), joint
locking, failure to respond to conservative therapy
Asymptomatic joint noise is common (in up to 35% of
Americans).
How does osteoarthritis of the TMJ manifest?
Degenerative joint disease or arthritis of the TMJ most
commonly affects the elderly population, but it can affect
all ages. Painful motion and joint loading are the hallmarks,
along with CT findings of DJD. Myofascial pain symptoms
must be ruled out. Unless related to ankylosis, it will not
vastly reduce range of motion.
What are the risk factors for septic TMJ arthritis?
History of trauma, burn, surgery or dental work, and systemic factors such as autoimmune disease, diabetes,
immunosuppression, sexually transmitted infection, or prolonged steroid use
What is the most common systemic inflammatory
condition to affect the TMJ?
Rheumatoid arthritis. Traditional rheumatologic laboratory
studies in addition to MRI are useful for establishing a
diagnosis.
What radiographic findings are expected in acute posttraumatic TMJ arthralgia?
Widening of the joint space might be seen, but radiographs
may also be entirely normal.
How should trismus be clinically evaluated in a
patient with head and neck cancer who has
undergone radiation?
Objectively measure the mouth opening (opening < 35 mm
is generally considered restricted) and compare with
subjective assessment of restriction as well as its effect on
daily functions. Assess for pain on opening or other
symptoms besides simple restriction of opening from
fibrosis.
What is the best initial therapy for postradiation
trismus?
Stretching exercises, including insertion of stacked tongue
blades or use of a commercial device such as Therabite. This requires multiple daily treatments over a period of months.
How should ankylosis of the TMJ be managed?
Many algorithms have been described, but most include a description of resection of the ankylotic mass with ipsilateral coronoidectomy. Reconstruction is often with costochondral grafting, with or without an interpositional
temporalis myofascial flap. Early and rigorous physiotherapy
is imperative.
Auriculocondylar syndrome is thought to develop from abnormalities in which branchial arches and
which craniofacial bones are most commonly affected?
Known also as Goldenhar syndrome, hemifacial microsomia, and branchial arch syndrome, it affects the first and second branchial arches. There is high variability of
expression and may affect the mandible, condyle, maxilla,
zygoma, orbit, and temporal bones.
Describe the clinical features of auriculocondylar
syndrome.
● Auricular abnormalities (question-mark ear with constricted middle to lower thirds of the pinna, auricular cleft)
● TMJ/condylar abnormality (mandibular hypoplasia, condylar hypoplasia, or dysmorphism)
● Facial asymmetry with chin deviation toward the affected
side
● Micrognathia
● Microstomia
Describe the clinical features of mandibular condylar hypoplasia.
Usually unilateral with mandibular deviation toward the affected side and severe malocclusion.
Define the condition of mandibular condylar
hyperplasia.
● Excessive, progressive unilateral growth of mandibular
condyle resulting in aesthetic and functional problems
such as facial asymmetry, occlusal disturbance, and joint
dysfunction
● Imaging must distinguish condylar hyperplasia from
osteochondroma.
● Condylar hyperplasia may also be described in terms of
hemimandibular hypertrophy and hemimandibular elongation
How does bone single-photon emission CT scan aid in the diagnosis of mandibular condylar
hyperplasia?
Technetium-99 radioisotope uptake is increased in the
hyperplastic condyle, which is indicative of unilateral
condylar activity. This is sensitive but nonspecific. Uptake is
also increased with inflammation, infection, and neoplasia.
Results should be interpreted along with clinical presentation.
Define myogenous temporomandibular disorders.
Pain and dysfunction of the TMJ area that results from
abnormal function or disease processes of the muscles of
mastication. It is also known as masticatory myalgia and includes the following subtypes: myofascial pain, myositis, muscle spasm, and muscle contracture.
What features characterize myofascial pain dysfunction syndrome (MPD)?
MPD is a dull, aching pain in the mandible, temple, or face
that is associated with specific trigger points and can
usually be reproduced by palpation of trigger points. Pain is
typically located over the muscles of mastication or neck
musculature rather than over the joint proper. MPD may be
with or without concurrent intra-articular disease.
What features characterize myositis of the masticatory musculature?
Diffuse, continuous pain over the entire muscle that may
limit range of motion and cause swelling. Inflammation of
the muscle is secondary to injury or infection, and pain
worsens with muscle use.
Describe the initial steps to treat masticatory
myalgia.
Rest the jaws and muscles by adhering to the following: soft
diet, avoiding caffeine, using heat or ice, take NSAIDs, avoid
parafunctional habits, avoid sleeping on the stomach, and
avoid excessive or prolonged jaw opening.
How is a patient with complex myogenous masticatory pain treated after conservative measures have failed?
A pain clinic or pain team is most useful. Physical therapy,
along with pharmacologic and lifestyle interventions, are helpful, as comprehensive treatment offers the best chances of success.
What differentiates masticator muscle contracture
from muscle contracture associated with masticator
muscle spasm?
Chronicity. Masticator muscle contracture is a chronic
condition with continued muscle shortening, whereas
masticator muscle spasm is an acute condition that is often
accompanied by pain.
