Mandible dislocation

(Redirected from Mandibular dislocation)

Background

Anterior Dislocation

  • Most common
  • Mandibular condyle is forced in front of the articular eminence
  • Risk factors: Prior dislocation, weak capsule, torn ligaments
  • Often occurs spontaneously while patient is yawning, "popping" ears, or laughing

Posterior Dislocation

  • Follows a blow to the mandible that may or may not break the condylar neck
  • Condylar head may prolapse into the external auditory canal

Lateral Dislocation

  • Often associated with mandibular fracture

Superior Dislocation

  • Occur from blow to the partially opened mouth
  • Associated with cerebral contusions, facial nerve palsy, deafness

Clinical Features

  • Inability to close mouth
  • Difficulty speaking or swallowing
  • Malocclusion
  • Pain localized anterior to the tragus
  • Prominent-appearing lower jaw
  • Preauricular depression
  • Condylar head palpable in the temporal space (in lateral dislocation)

Posterior Dislocation

  • Must examine the external auditory canal

Differential Diagnosis

Jaw Spasms

Evaluation

  • Generally a clinical diagnosis
  • For traumatic etiology, obtain CT face to evaluate for fracture
    • Also obtain CT IAC if concern for posterior dislocation
  • Examine external auditory canal, especially in posterior dislocation
  • Evaluate the cranial nerves to rule out concomitant injury

Management

  • Closed reduction in the emergency department (if no concern for fracture)
    • If dislocation is bilateral, may be easier to relocate one side at a time.
  • Pain control or anxiolysis
    • Consider local analgesia - inject local anesthetic into the preauricular depression just anterior to the tragus.
  • Consider procedural sedation

Wrist Pivot Method[1]

Wrist-pivot-method.jpg
  • Place patient in seated position
  • While facing the patient, grasp the mandible with your thumbs at the apex of the mentum and fingers on the occlusal surface of the inferior molars.
  • Apply cephalad force with the thumbs and caudad pressure with the fingers
  • Then pivot your wrists.
  • Note: This is a more physiologic reduction technique for the provider, allowing greater and more sustained force to be exerted.

Older "Traditional" Technique

Posterior position
  • Place patient in seated position (anterior approach) or supine (posterior approach)
    • Advisable to wrap thumbs in gauze to guard against accidental bite
  • Placed gloved thumbs in patient's mouth over the occlusal surfaces of the molars, or lateral to patient's molars in buccal fold (to avoid being bitten)
  • Apply pressure downward (toward the feet) and then backward (posteriorly)

Disposition

  • Generally may be discharged if uncomplicated and successfully reduced
    • Instruct patient to use soft diet, not to open mouth wider than 2cm for 2 weeks, and to support mouth when yawning
  • Admit for:
    • Open dislocation
    • Superior dislocation
    • Fracture
    • Nerve injury
    • Inability to reduce

References

  1. Lowery LE, Beeson MS, Lum KK. The wrist pivot method, a novel technique for temporomandibular joint reduction. J Emerg Med. 2004 Aug;27(2):167-70. http://www.ncbi.nlm.nih.gov/pubmed/15261360

Authors:

Michael Holtz