OMFS - Trauma Flashcards
What is the relevance of the muscles of mastication in relation to mandibular fracture?
These muscles can cause displacement of the fracture
(Displacement dictates management)
What are the signs and symptoms of mandibular fracture? (11)
- Pain
- Swelling
- Limited function (opening and lateral movements)
- occlusal derangement = Can’t bite as normal into ICP
- Numbness lower lip
- Mobility of teeth/loose teeth
- Bleeding limited to area of fracture
- AOB
- Facial asymmetry
- deviation of mandible towards opposite side to fracture
- bleeding in FOM
What is a specific symptom of a condylar mandibular fracture?
Bleeding of the ear
How do we classify a mandibular fracture? (7+)
- Involvement of the surrounding soft tissue;
* Simple: surrounding soft tissue intact
* Compound: fracture exposed to the surrounding environment (soft tissue breached)
Need AB’s
* Comminuted: multiple small fragments e.g. from gunshot - No of fractures
* Single
* Double
* Multiple - side of fracture
* Unilateral
* Bilateral - Site of fracture
* Angle
* Below condyle (subcondyle)
* Parasymphyseal (in the middle)
* Body
* Ramus
* Coronoid
* Condylar fracture (intra/extra caspular)
* Alveolar process - Direction of fracture line
* Favourable:
* Unfavourable - Specific fractures
* Green stick fracture: soft bone (children) very unlikely to completely fracture = still attachment in one of the cortices
* Pathological: fracture caused by pathology - Displacement of the fracture
* Displaced
* Undisplaced
What is the difference between a simple and compound fracture?
- Simple: surrounding soft tissue intact
- Compound: fracture exposed to the surrounding environment (soft tissue breached)
What is required if there is a compound fracture?
antibiotics
If a fracture breaches the tooth bearing area of the mandible what is it automatically classified as and why?
compound fracture
as it is In direct communication with the PDL (Gingival crevice) = surrounding environment
What is a comminuted fracture?
what is it commonly caused by?
multiple small fragments of fracture
gunshot
What makes a fracture favourable?
direction of fracture line limits the displacement of the fracture by the action of the surrounding muscles
What makes a fracture unfavourable?
direction of fracture line encourages the displacement of the fracture
What conditions can cause a pathological fracture to the mandible? (5)
osteoporosis, osteomyelitis, Padgets, expanding cystic lesion
What factors cause displacement of the mandibular fracture? (6)
- Direction of fracture line
- Opposing occlusion: prevents fracture being displaced
- Magnitude of force
- Mechanism of injury
- Intact soft tissue: intact tissue = displacement unlikely
- Other associated fractures: > 1 fracture = higher chance of displacement
What radiographic views do we use for assessing/locating mandibular fractures? (6)
2 Plain views at 90 degree angles to each other;
OPT + posteroanterior mandible
Other radiographs:
Most common now = CT scan or CBCT
- Occlusal
- Lateral oblique
- Towns view
- SMV
How do we treat mandibular fractures? (3)
Control pain and infection via NSAIDS & AB’s
Reduction
Fixation
What are the 2 basic principles of treating a mandibular fracture?
Describe.
- Reduction: to reduce the displaced fragment back to its normal anatomical orientation
- Fixation: to fix the fractured segment in place using plates and screws (internal fixation)
What is usually the tx option of choice for an undisplaced mandibular fracture?
No tx
What is usually the tx option of choice for a displaced/mobile mandibular fracture?
What is the other option?
ORIF
open reduction internal fixation
Closed reduction +/- fixation
Describe closed reduction.
reduce the fractured segments to their normal anatomical orientation without exposing the fracture line
= No periosteal exposure of the fracture segment
In closed reduction how do we ensure that the displaced mandibular fragment has been reduced to its original/desired site if we cannot directly see the fracture line?
Intermaxillary fixation = if teeth go into ICP
In a closed reduction approach how to we ensure fixation of the mandibular segments?
Intermaxillary fixation
= teeth go into ICP & wire teeth together
What is the contraindication of intermaxillary fixation of the mandible?
Epilepsy
What are the risks associated with ORIF of the mandible? (2)
All surgical risks
Damage to vital structures e.g. nerves
What must be considered before carrying out a ORIF approach in the mandible? How do we combat this?
Thin mandibular bone in px’s with disease of the bone (osteoporosis)
= requires rib bone graft before plates placed for ORIF
What specific type of mandibular fracture causes AOB?
Describe how this causes AOB.
Subcondylar (bilateral)
Causes shortening In vertical height of ramus
(posterior teeth meet prematurely)
List 3 radiographic signs of mandibular fracture.
- Loss in continuity of the inferior mandibular border
- Step deformity in occlusion
- Radiolucent line
List the classifications of maxillofacial fractures. (4)
- Nasoethmoidal fractures
- Lateral middle third (zygoma)
- Central middle third
- Mandibular fractures
List the classifications of central middle 1/3rd facial fractures. (5)
- Nasal bone
- Unilateral maxillary fracture
- Le fort 1 fracture
- Le frot 2 fracture
- Le fort 3 fracture
Various combinations
Which structures can be damaged after an anterior wall orbital naso-ethmoidal injury? (3)
- Eyelids
- Cornea
- Sclera
Which structures can be damaged after a medial wall orbital naso-ethmoidal injury? (6)
- Medical rectus muscles (action affected)
- Nose
- Lacriminal duct and sac
- Medial canthal ligament
- Ethmoid sinus
- Cribriform plate
Which structures can be damaged after a superior orbital fissure orbital naso-ethmoidal injury? (5)
- Oculomotor nerve: function = supply all muscles of the eye
(except lateral rectus and superior oblique) - Trochlear nerve (4)
- Abducent nerve (6)
- Branches of the Ophthalmic nerve
- Ophthalmic veins
Which structures can be damaged after an inferior orbital fissure orbital naso-ethmoidal injury? (3)
- Infraorbital nerve
supplies = lateral side of nose, cheek, skin underneath the eye (3 branches from the foramen) - Infraorbital vein
- Infraorbital artery
What does the infraorbital nerve supply? (4)
lateral side of nose
cheek
skin below eye
top lio
What are the signs and symptoms of a zygomatico-orbital fracture? (8)
- Numbness (below the eye)
- Facial asymmetry
- Pain
- Bruising
- Swelling
- Flatness of the face
- Difficulty/paralysis of the eye
- Restricted eye movement and diplopia (double vision)
Why does the patient complain of not being able to move the eye after a ZO fracture?
damage to the oculomotor nerve which supplies mostly all of the muscles of the eye
= superior orbital fissure syndrome/damage
Why does the patient complain of double vision after a ZO fracture?
from entrapment of the recti muscle
How do we examine the bones of the maxillofacial region after trauma? (3)
Palpate the;
- superior orbital ridge
- infrorbital ridge & prominence of the zygoma
(does the cheekbone appear flat?) - intra-oral palpation to assess for maxillary mobility
How do we examine the muscles and nerves of the eye after maxillofacial trauma?
Movements of eyes;
- Centre
- Upwards to the right, centre, left
- Downwards to the right, centre, left
How do we examine the soft tissues after maxillofacial trauma? (3)
Assess for Subconjunctival haemorrhage
Circum/periorbital ecchymosis (bruising)
Subcutaneous emphysema
What other signs do we look for after maxillofacial trauma? (2)
Explain why these can present.
Epistaxis = Bleeding from the nose: bleeding in maxillary sinus, maxillary sinus connected to nose via middle meatus
Limited mouth opening: damage to the zygoma interferes with the coronoid process
Describe two ways in which ZO complex fractures can present radiographically.
radiopaque sinus
reduced length of zygoma
Whats involved in the inital stage of ZO fracture treatment? (3)
- Exclude ocular injury
- Prophylactic AB’s
- Avoid nose blowing
When do we review a patient with a ZO complex fracture?
What is carried out at this visit? (2)
Review once swelling subsided
- Further radiographs (+/- CT)
- Informed consent
What are the definitve tx options for a ZO complex fracture?
- Closed reduction +/- fixation
- Open reduction + internal fixation
- Most corrections have ORIF
