Physical Examination Maneuvers for Temporomandibular Joint (TMJ) Evaluation
A standardized approach to TMJ physical examination should include visual inspection, palpation of muscles of mastication, TMJ movement evaluation, and assessment of associated structures to accurately diagnose TMJ disorders and guide appropriate management. 1
Core TMJ Examination Components
Visual Inspection
- Observe facial symmetry and mandibular alignment
- Note any swelling or asymmetry in the TMJ region
- Assess for signs of teeth grinding (wear facets)
- Examine occlusion and dental alignment
Palpation Techniques
- Palpate the TMJ laterally during opening and closing movements
- Palpate muscles of mastication:
- Masseter muscles (anterior border of ramus and angle of mandible)
- Temporalis muscles (temples)
- Medial and lateral pterygoid muscles (intraoral approach for medial, extraoral for lateral)
- Note tenderness, hypertrophy, or trigger points
Range of Motion Assessment
- Measure maximum unassisted jaw opening (normal: 35-50mm)
- Measure maximum assisted jaw opening
- Assess lateral excursions (normal: 8-12mm)
- Evaluate protrusive movements
- Document any midline deviation during opening
Joint Sound Evaluation
- Listen and feel for clicking, popping, or crepitus during opening and closing
- Note at which point in the range of motion sounds occur
- Assess joint sounds with and without compression
Specialized Maneuvers
Joint Loading Test
- Apply gentle pressure to the TMJ while the patient performs opening and closing movements
- Positive test: Reproduction or exacerbation of pain
Clench Test
- Have patient clench teeth in various positions
- Assess for pain reproduction or changes in symptoms
End-Feel Assessment
- Apply gentle pressure at maximum opening
- Evaluate whether limitation is due to muscle guarding (soft end-feel) or internal derangement (hard end-feel)
Additional Assessment Components
Cranial Nerve Examination
- Assess cranial nerves V and VII for proper function
- Evaluate for abnormal reflexes or sensory changes
Occlusal Evaluation
- Check for malocclusion, crossbites, or other dental abnormalities
- Assess for excessive wear facets indicating bruxism
Diagnostic Considerations
The physical examination findings should be correlated with imaging when indicated. For TMJ ligament-capsule tissue disorders, MRI is recommended, while for TMJ bone disease, CBCT or CT scan is indicated 2. Panoramic radiography (OPT) is of limited diagnostic value for TMJ assessment 2.
It's important to note that while physical examination is valuable, it has limitations in detecting TMJ inflammation. Studies have shown that clinical examination correctly identified only 58% of patients with active TMJ arthritis compared to MRI findings 2. Therefore, contrast-enhanced MRI remains the best method to detect active TMJ arthritis when clinically indicated 2.
Common Pitfalls to Avoid
- Relying solely on joint sounds for diagnosis (clicking may not always indicate disc displacement with reduction) 3
- Failing to assess both TMJs, as the condition can be unilateral or bilateral
- Overlooking the contribution of head and neck muscles to TMJ symptoms
- Not considering psychosocial factors that may influence TMJ disorders
By systematically performing these physical examination maneuvers, clinicians can better assess TMJ status and determine when additional diagnostic testing or referral to specialists is warranted.