Head and mandibular fractures

• How do you do the initial assessment of facial trauma and fracture?

  Assess the animals state of consciousness and awareness of its surroundings. Can it walk in a co-ordinated fashion?

  Assess the head for symmetry. Is the animal able to close its mouth? If not this may indicate fracture of either the mandible or maxilla or broken teeth?

  Are the pupils symmetrical? Is there a menace reflex?
• What is the imaging assessment for facial trauma and fractures?

  Radiographic assessment - difficult due to superimposition of many structures.

  Orthogonal views and occasionally oblique views can be helpful.

  The views should be well positioned and avoid asymmetry although this can be difficult.

  CT is vastly superior at imaging the traumatised skull as it avoids superimposition of structures and facilitates 3D reconstructions, allowing compensation for non-symmetrical objects.

  
• What are the surgical consideration for fractures of the skull and mandible?

  The most important clinical outcome is for patient to be able to close its mouth and any depression fractures to the brain are addressed.

  Surgery is best performed with either a tracheal or pharyngeal ET tube. Relatively weak fixation is adequate in these non-load bearing bones.

  Mandibular fractures are invariably open and antibiotics are advisable. Repairs should avoid any damage to the tooth roots. The placement of a feeding tube at the time of surgery is advisable.
• What are the surgical considerations for fractures of the mandible?

  Many techniques are available, including external coaptation of the muzzle in which interdigitation of the teeth maintains the fracture reduction. The simplest form of coaptation is the use of a muzzle to keep the mouth closed, this can be acheived by inter-canine acrylic bonding.
• What are surgical options for fractures of the skull and mandible?

  Intercanine acrylic bonding.

  External fixator.

  The BEARD (Bi-gnathic encircling and retaining device) technique.

  Plating

  Interfragmentary wiring of the mandible/maxilla
• Fractures of the skull and mandible - salvage procedures

  There are occasions when the fractured mandible or maxilla cannot undergo reconstruction.

  Or the fracture is pathological e.g. severe periodontal disease. In these cases a partial mandibulectomy or maxillectomy can be performed. This is well tolerated and is used extensively in oncological surgery.
• Temporomandibular joint fractures - over view

  Seen most commonly in the cat and fragments are too small to fix. CT is invaluable in assessing these fracture types. If there is little displacement then feeding soft foods for 4-6 weeks maybe all that is required. If there is marked instability of malalignment then closed or open mouth fixation can be used. Osteoarthritis is a common but usually asymptomatic result of this injury.
• Temporomandibular dysplasia (locking jaw syndrome) - overview

  Basset hounds and Persian cats over represented.

  Jaw locks open with slight deviation to side of the lock when the vertical ramus/ coronoid process engages on the ventral zygomatic arch.

  Occurs when yawning and can be present in both sides. It is due to increased lateral medial laxity in the TMJ.

  Treatment is by partial resection of the ventral region of the zygoma. Tends to go in one particular direction so only have to do one side.
• Temporomandibular ankylosis

  This can be intracapsular or extracapsular, both result in an inability to open the mouth.