Temporomandibular joint dislocation

Dr Ian Bickle et al.

Temporomandibular joint dislocation represents the condyle of the mandible being abnormally displaced, with a loss of the normal articulation with the glenoid fossa.

Epidemiology

Dislocations of the temporomandibular joint (TMJ) are common and occur in as many as 7% of the entire population, at some point in their lives 3.  They can occur at any age but are most common between 20-40 years of age 3

Pathology

Dislocations can occur in a number of directions 1

  1. anterior dislocation (common)
  2. cranial dislocation (uncommon)
  3. posterior dislocation (rare)
Anterior dislocation

Anterior dislocations are most common and represent either an exaggerated and often recurrent (also known as habitual) normal anterior translation of the condyle out of the glenoid fossa and onto the condylar eminence (see TMJ dysfunction), or the result of acute and forceful opening of the mouth (e.g. trauma, intubation 2 etc...) 1,3. In some settings, the dislocation may not be reduced and become chronic. 

Cranial dislocation

Cranial dislocations are quite uncommon and are the usually the result of an upward blow to the mandible such that the condyle fractures the glenoid fossa and protrudes into the middle cranial fossa 1.  

Posterior dislocation

Posterior dislocations are rare. 

Share article

Article Information

rID: 51576
System: Head & Neck
Tag: stub
Synonyms or Alternate Spellings:
  • TMJ dislocation

Support Radiopaedia and see fewer ads

Cases and Figures

  • Drag
    Case 1: temporomandibular joint dislocation
    Drag here to reorder.
  • Drag
    axial partes mole...
    Case 2
    Drag here to reorder.
  • Drag
    Case 3
    Drag here to reorder.
  • Drag
    Case 4
    Drag here to reorder.
  • Drag
    Case 6
    Drag here to reorder.
  • Drag
    Case 5
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.