Pain:TMJ Screening Examination

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The TMJ Screening Examination is a structured clinical protocol for assessing temporomandibular joint (TMJ) disorders prior to and alongside myofascial assessment. It is indicated whenever a patient presents with ear, jaw, cheek, or temporal pain. The protocol described here follows Chapter 5, Section C of Travell & Simons' Myofascial Pain and Dysfunction: The Trigger Point Manual.

The examination screens for the following TMJ disorder categories:

  • Congenital disorders
  • Disc derangement disorders
  • Osteoarthritis
  • TMJ dislocation
  • Ankylosis
  • Condylar process fracture
  • Inflammatory disorders (capsulitis, synovitis, retrodiscitis)

Joint Palpation

Lateral Pole Palpation — Capsular Inflammation

The lateral poles of the condyles are found just anterior to the tragus of the ear, where movement can be felt when the mouth opens and closes. This tests for capsular inflammation.

Technique:

  1. Simultaneously apply pressure to both joints with the tip of the index fingers, just anterior to the tragus of each ear
  2. Ask the patient to open and close slowly

Interpretation:

  • Firm palpation may be uncomfortable in a normal joint, but should not be painful
  • Pain on palpation indicates capsular inflammation
  • Simultaneous bilateral palpation allows the patient to compare one side to the other — this is important for identifying asymmetric tenderness

Retrodiscal Tissue Palpation

The posterior superior part of the joint, where potentially inflamed retrodiscal tissues are located, is accessed through the external auditory meatus.

Technique:

  1. Place the little fingers just inside each external auditory meatus
  2. Gently press downward on top of the joint (anteriorly)
  3. Ask the patient to open and close

Interpretation:

  • A normal joint may exhibit discomfort with this palpation but should not be painful
  • Pain indicates inflammation of the retrodiscal tissues

Clinical Note — Periarticular Pain Without True Inflammation

An important clinical observation is the complaint of persistent periarticular TMJ pain without true joint inflammation. In this situation:

  • Any tenderness to joint palpation is relatively mild compared to that seen with acute inflammatory conditions
  • The source is referred pain from masseter, pterygoid, or SCM TrPs, with associated secondary referred cutaneous and deep tissue hypersensitivity
  • Clinical significance: Acute inflammatory TMJ pain should be referred to a dentist trained in orofacial pain and TMJ disorders. Myofascial referred pain to the joint does not require dental referral — it requires identification and treatment of the responsible TrPs.

Joint Noise Assessment

Auscultation with a stethoscope has a kappa value of 50–65% for TMJ sounds. The following characterisations are clinically useful:

Sound Characteristics Clinical significance
Rough, sandy, or diffuse noise/vibration Crepitus throughout range Degenerative joint changes (osteoarthritis)
Reciprocal click Louder click on opening at wide aperture; quieter click on closing just before teeth meet Anteriorly displaced disc with reduction — disc reduces on opening, re-displaces on closing
Discrete click at same point on opening and closing Consistent location in both directions Discrete disc or articular surface abnormality
Click on contralateral excursion An involved right joint clicks when jaw moves left, and vice versa Confirms intra-articular involvement

Note: Not all intra-articular interferences with joint movement will produce noise.

Mandibular Range of Motion

Normal Values

  • Interincisal opening: 36–44 mm (measured between central incisor teeth)
  • Practical bedside test: patient should be able to fit two knuckles of the non-dominant hand between the upper and lower teeth
  • Opening > 60 mm = clinically significant TMJ hypermobility

Path of Opening

Observe the path of opening and closing without measuring first. Note deflections and deviations from the midline:

Finding Definition Clinical significance
Deviation Jaw moves away from midline then returns by full opening Internal derangement with reduction; elevator muscle TrPs on the side of deviation
Deflection Jaw moves away from midline and does not return Internal derangement without reduction; ankylosis; ROM restriction — jaw deflects toward affected side

End Feel

  • Soft end feel with restricted opening → muscular splinting, TrPs, tight joint capsule
  • Hard end feel with restricted opening → possible ankylosis or anteriorly displaced disc without reduction

Restricted Opening — Clinical Decision

Finding Action
Restricted opening, responds to spray and stretch Myofascial TrPs — treat accordingly
Restricted opening, responds to joint mobilisation with 5–10 mm improvement Tight joint capsule — mobilise
Restricted opening, does not respond to either Possible ankylosis or anteriorly displaced disc without reduction — refer to specialist in TMJ disorders
< 36 mm opening + deflection + hard end feel Refer to specialist in TMJ disorders

Mobilisation Techniques

These may be used to assess and treat restricted opening:

  • Pull the jaw forward from the lower incisors without opening — distracts the joint anteriorly
  • Pump the second molar down to distract the joint on the affected side
  • Apply lateral force to the second molar

If joint capsule tightness is present, 5–10 mm of improvement should occur with these techniques.

Indications for Referral

Refer to a dentist trained in orofacial pain and TMJ disorders when:

  • Acute inflammatory TMJ pain (capsulitis, synovitis, retrodiscitis) is confirmed
  • Restricted opening with deflection and hard end feel
  • ROM does not respond to spray and stretch or joint mobilisation
  • Reciprocal click is painful
  • Episodes of locking are reported
  • History of open dislocations
  • Clicking that is painful, associated with locking, or associated with episodes of open dislocation — stretching should be avoided in these cases

Palliative Management

For capsulitis, synovitis, or acute-stage arthritis:

  • Soft diet
  • Reduce all abusive oral and jaw habits
  • NSAIDs for 7–10 days
  • Cold or ice pack over one joint — 10 minutes on, 10 minutes off, 2–3 times per day

Definitive Management Considerations

Predisposing Factors

  • Skeletal and craniofacial disharmonies
  • Abnormal biomechanical loading (significant occlusal change or tooth loss)
  • Chronic microtrauma (bruxism, chronic clenching, excessive gum chewing)

Precipitating Factors

  • Macrotrauma
  • Emotional tension
  • Arthritis
  • Any source of chronic deep pain input

Occlusal Appliance Therapy

Consider referral for occlusal appliance therapy in patients who:

  • Have painful internal derangements, and/or
  • Report significant parafunction (chronic daytime clenching, nocturnal bruxism, focal jaw or temple pain on awakening, gum chewing or nail biting habits), and/or
  • On examination have evidence of notable occlusal wear (lock and key patterns of anterior teeth with excursive movements, flattening of molar cusps), and/or
  • Have myalgia

Abusive Oral Habits to Eliminate

  • Gum chewing
  • Fingernail biting
  • Pen or pencil biting
  • Resting the chin in the hand
  • Clenching during concentration or physical exertion

References

  • Travell JG, Simons DG. Myofascial Pain and Dysfunction: The Trigger Point Manual, Volume 1: The Upper Half of Body. 2nd ed. Baltimore: Williams & Wilkins; 1999. Chapter 5, Section C.