| Dislocation Type
|
Frequency
|
Associated with trauma?
|
Mechanism
|
Additional Comments
|
Associated with fracture?
|
Image
|
| Anterior
|
|
|
- Spontaneously while patient is yawning, "popping" ears, or laughing
- Risk factors:
- Prior dislocation
- Weakness or laxity of capsule
- Ligamentous injury
|
- Mandibular condyle forced in front of the articular eminence
- May happen bilaterally or unilaterally
|
|
|
| Posterior
|
|
|
- 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
|
|
|
- Lateral trauma to mandible
|
- Often associated with mandibular fracture
|
|
|
| Superior
|
|
|
- Occur from blow to the partially opened mouth
|
- Can result in a fracture of the glenoid fossa and displacement of the condyle into the middle cranial fossa, potentially injuring the facial and vestibulocochlear nerves and the temporal lobe.
- Associated with cerebral contusions, facial nerve palsy, deafness
|
|
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