S2 - Maxillofacial Injuries Flashcards
(40 cards)
Name 3 common causes of maxillofacial injuries
- interpersonal violence
- RTA (road traffic accident)
- falls
also sport
Which pt group is most susceptible to maxillofacial injuries
males, age 13-35
Most common maxillofacial fracture
- nasal fractures (most common)
- mandibular fractures (next most)
Components of treating a pt who has maxillofacial injury
- initial assessment
- applied anatomy (what is broken, fractured, lacerated etc)
- diagnosis
- treatment planning
- principles of treatment
- definitive treatment
- complications of fractures
What should be done in initial assessment? (6)
- rapid survey of vital functions & prioritize management options
- ABCDE (airway, breathing, circulation)
- head injury
- prevent infection
- pain management
- temporary immobilisation/fixation of fractures (helps stop pain and haemorrhage)
*During head injury, the face might be very injured/broken by absorbing the force from the injury but this may have prevented PRIMARY brain injury. E.g. a patient with severe face injury is conscious and alert, but what is now important to prevent?
prevent secondary brain injury from inadequate cerebral circulation:
- airway - 100% oxygen
- breathing - chest injury
- circulation:
- control haemmorhage
- treat hypovolaemia
- isotonic fluid therapy (to raise blood pressure in pt w hypovolaemia)
For context: haemorrhage vs hypovolaemia
haemorrhage - loss of blood from ruptured/injured blood vessels
hypovolaemia - fall in circulatory volume
can have hypovolaemia due to haemmorhage
What to know about head injury?
- frequently associated with facial injury
- may be milder when associated with severe facial injury
- often associated with alcohol/drug use
Applied anatomy of the face which may be affected by maxillofacial injuries
- dento-alveolar
- mandible
- middle 1/3 of face
- zygoma
- orbit
- nasal bones & naso-ethmoidal complex
- cranio-facial (shared)
How to diagnose the injury?
- history (to understand what happened)
- examination
- recognition of diagnostic features**
- imaging
- study models (e.g. to show how broken maxilla or md fit tgt)
What are some soft tissue structures often damaged?
- parotid gland
- parotid duct (Stensen’s duct)
- branches of facial nerve
- muscles of facial expression
- sensory nerves (supraorbital, infraorbital)
- nasolacrimal duct
Branches of the facial nerve
TZBMC
Temporal
Zygomatic
Buccal
Marginal mandibular
Cervical
**4 principles of managing a fracture
- Reduction: reduce fracture by putting broken ends tgt in anatomical position
- Fixation (ORIF): open reduction internal fixation - open wound and fix bones in correct position
- Immobilisation (IMF): intermaxillary fixation - wiring teeth together to stabilise face/jaws
- Rehabilitation
Best way to treat a nasal fracture and why?
push nasal bones back into place straightaway, if you wait too long oedema wont allow pushing it back
can put splint on after to protect broken bones
How does mandibular fracture commonly occur?
- direct injury to parasymphyseal/mental region
- can lead to indirect injury to the condyle and angle (areas of weakness in md) - on opposite side
(angle = where horizontal body meets vertical ramus, can have impacted 3rd molars in this area too, neck of condyle is thin and narrow - postulated that it has evolved so injury to chin doesnt cause md to go into temporal area and cause cranial damage and instead the condyle neck fractures)
Types of mandibular fractures (by region) and how
parasymphyseal/mental and body - direct injury
angle and condyle - indirect
ramus and condyle - very rare, may be associated with severe, communited fractures in multiple fragments(??)
What injury is shown
left parasymphysis (direct) and right condyle (indirect) #
classic presentation
What injury is shown?
right parasymphsis (direct) and left angular fracture (indirect) - weak spot at 3rd molar
**Diagnostic features of unilateral condyle fracture. (5,2) What is usually an accompanying problem?
Afffected side:
- pain in joint, worse on moving
- tenderness & swelling
- absent/abnormal movements of condylar head
- deviation of mandible on opening
- premature contact on molars
Opposite side:
- open bite
- limited lateral excursion (cant move)
i.e. when pt opens mouth, jaw deviates to side of #
Rarely by itself, usually parasymphyseal fracture on other side
Which is more common, unilateral or bilateral condyle fracture
bilateral
Diagnostic features of bilateral condyle fracture. (4)
- pain, tenderness, swelling over both joints
- premature contact on posterior teeth and AOB
- restricted lateral movements (isnt going anywhere laterally)
- absence of movement of condylar heads
may be caused by falling right onto chin - midline symphyseal fracture + bilateral condyle
Diagnostic features of body of mandible fractures. (7) Specify the pathognomonic feature.
- pain on moving jaw
- trismus
- movement/crepitus (scraping) at fracture site
- step deformity of lower border
- derangement of occlusion
- mental nerve anaesthesia
- haematoma of FOM/buccal sulcus (pathognomic!)
Treatment for mandibular fracture
ORIF (open reduction internal fixation) - titanium plates used to hold in place after fracture is reduced, occlusion of teeth can be a guide to position
IMF (temporary inter-maxillary fixation) - can be used to stabilise occlusion just intraoperatively or sometimes left on for weeks so that occlusion is correct as bone heals
Diagnostic features of zygoma fractures (9)
- depression of cheek prominence
- step deformity of infra-orbital ridge
- subconjuctival haemorrhage* (pathognomonic)
- diplopia (double vision)
- infra-orbital nerve anaesthesia
- trismus (zygoma impacts into coronoid process)
- blood in antrum
- circumorbital ecchymosis (black eye)
- retrobulbar haemorrhage
*bruise under conjuctiva stays red as oxygen can pass across conjunctiva
cheekbone designed to break when hit in order to protect eye
sometimes present to dentist due to trismus and numb upper anterior teeth and lip
