Temporomandibular Joint (TMJ) Dislocation

Definition: Displacement of the mandibular condyle from the temporomandibular fossa.

Epidemiology:

• Anterior dislocations are most common
• Mechanism
  • Atraumatic (most common) from extreme mouth opening (yawning, eating, dental procedure, etc).
  • Traumatic: superior and posterior dislocations more common in trauma
• TMJ dislocations typically occur bilaterally.

Diagnosis:

• Diagnosis can be made based on clinical exam alone
• Physical exam
  • Inability to close the mouth
  • Garbled speech
  • Drooling.
  • Anterior dislocations: Palpation of the TMJ can reveal one or both of the condyles to be anteriorly displaced in front of the articular eminence.
• Imaging (X-ray or CT)
  • Helpful when patient has subtle presentation
  • Should be obtained in traumatic dislocations as concomitant fracture is common

Management

• Atraumatic TMJ dislocations are typically managed non-operatively with ED reduction
• Supportive Care
  • Provide analgesia as needed
  • Local anesthestic (2-3cc) can be injected into the TMJ space or directly into the lateral pterygoid muscle
  • Consider procedural sedation as muscle spasm often limits success of reduction techniques
• Reduction Techniques
  • Gag Technique
    • Elicit a gag reflex using a tongue depressor
    • This reflex inhibits the muscles of mouth closure, thereby potentially allowing the condyle to move downward past the anterior lip of the mandibular fossa and relocating posteriorly
  • Traditional (intraoral)
    • Place the patient in an upright seated position
    • While facing the patient, place bilateral thumbs (wrapped in gauze) on the inferior molars and the remainder of fingers around the outside of the jaw
    • Apply downward and backward pressure to facilitate the condyles from the anterior aspect of the articular eminence
    • Have another person hold the patient’s head to prevent movement
    • This can also be done while standing behind and above the patient. You can use your abdomen brace the patient’s head
  • Wrist pivot
    • While facing the patient, grasp the mandible with both thumbs under the chin and place fingers on the occlusal surfaces of the lower molars
    • Apply upward force with the thumbs and downward pressure with the fingers while pivoting the wrist forward
    • Force must be equally applied to all sites to prevent fracture.
  • Extraoral
    • With one hand, grab the mandibular angle with fingers and place the thumb over the malar eminence of the maxilla
    • With the other hand, place the thumb just over the displaced coronoid process and fingers behind the mastoid
    • Simultaneously pull the mandibular angle forward on one side while pushing the coronoid process on the other causing one if not both TMJs to relocate back in the appropriate position
  • Syringe Technique (Gorchynski 2014)
    • Place a 5 or 10 cc syringe between the upper and inferior molars of the affected size
    • Syringe size is determined by the mouth opening of the patient
    • Instruct the patient to roll the syringe back and forth between the teeth, until reduction is achieved
    • Success rate: 97% (30/31)
• Post-reduction Care
  • Advise patient to avoid extreme mouth opening and to eat soft foods for 1 week
  • Follow-up with ENT or oral surgery as needed
  • Chronic dislocations may require surgical fixation

Take Home Points

• Atraumatic TMJ dislocations are typically anterior in nature and can be reduced by a variety of techniques in the ED
• Traumatic TMJ dislocations often involve mandible fractures and typically require open reduction and fixation in the operating room
• Consider using the syringe, gag and extraoral reduction techniques first line as they frequently do not require parenteral analgesics or procedural sedation

ALiEM: Tick of the Trade: Extra-oral reduction technique of anterior mandible dislocation

Core EM: Podcast 47.0 – TMJ Dislocation

Core EM: TMJ Dislocation Reduction Techniques

References:

Amsterdam JT: Oral Medicine, in Marx JA, Hockberger RS, Walls RM, et al (eds): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 8. St. Louis, Mosby, Inc., 2010, (Ch) 70: p 895-909.

Gorchynski J et al.  The “syringe” technique: a hands-free approach for the reduction of acute nontraumatic temporomandibulardislocations in the emergency department.  J Emerg Med. 2014; 47(6):676-81. PMID 25278137

Marx JA et al. Rosen’s Emergency Medicine: Concepts and Clinical Practice, 7 ed. Philadelphia: Mosby Elsevier, 2010.

Mendez DR et al. Reduction of temporomandibular joint (TMJ) dislocations. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA.

Riviello RJ. Otolaryngologic Procedures. Roberts & Hedges’ Clinical Procedures in Emergency Medicine. Philadelphia: Elsevier Saunders, 2014. 6 ed. Ch 63: 1298-1341