The facial skeleton is designed to withstand the vertical forces associated with mastication but it collapses readily when struck from the front. Injuries can be divided into lower third (mandible), middle third and upper third (frontal). The last type is considered in Chapter 3.
Facial fractures are not always obvious. Examination begins with an assessment of facial contours often best achieved by looking at the face from above and behind. Bony tenderness may be difficult to detect if soft-tissue bruising and swelling are already present. However, pressure for a few seconds over bony points (e.g. the infraorbital margin) will usually displace sufficient interstitial fluid to allow assessment of bony contours and orbital contents.
Facial Radiography
The head position required to obtain basal skull and occipitomental views can be dangerous in the presence of cervical spine injuries. These can never be excluded immediately in the severely injured patient and so it is unwise to request these views in such patients. The usual brow-up, lateral view has two advantages: (1) minimal patient movement and (2) easier demonstration of paranasal sinuses. A CT scan overcomes these problems but should not be undertaken at the expense of treating more immediately important injuries.
Antibiotics for Compound Fractures
Flucloxacillin is appropriate prophylaxis for fractures associated with skin wounds. When there is a fracture into a sinus, then phenoxymethylpenicillin or equivalent is probably a better choice.
Special Features Associated with Facial Fractures
Surgical Emphysema of the Face
This indicates the presence of a fracture into an air-containing sinus. Antibiotics and referral are required.
Facial Sensory Loss
Anaesthesia in the area of distribution of the infraorbital nerve (terminal branches of Vb) is often associated with:
- fractures of the malar complex
- fractures of the floor of the orbit
- Le Fort II and III fractures
- severe soft-tissue injuries to the cheek.
The area of numbness may include the ipsilateral upper lip and also the anterior gums and teeth (anterior superior alveolar nerve). Oedema in the infraorbital canal is the usual cause. This is where the dental nerve separates off, leaving the terminal part of the maxillary nerve to exit from the infraorbital foramen as the infraorbital nerve. Oral surgical follow-up is indicated.
Intraoral Damage
Examination inside the mouth is very important. Malocclusion of teeth, or displacement of dentures in the absence of primary dental damage, is always associated with injury to bone or to the temporomandibular joint (TMJ). Palatal irregularities suggest a Le Fort fracture. Inability to open the mouth fully should provoke a careful look at the mandible.
Injuries Affecting the Eye
Assessment of visual acuity, conjunctival sac, cornea, anterior chamber and fundus is an essential part of facial assessment. Displacement of the eye, inwards or downwards, is associated with injury to the infraorbital plate. Extraocular muscle damage or distortion may complicate any damage to the bony wall of the orbit and is clearly demonstrated on testing the full range of eye movements. The presence of a subconjunctival haemorrhage without evidence of direct trauma to the eye is a strong indication of the presence of a facial fracture, usually in the infraorbital region.
Wounds Associated with Major Fractures
Closure of major wounds associated with displaced facial fractures must await reduction of the fractures. The wounds may offer surgical access to bone and facilitate reduction. Until this has been carried out it may not be possible to achieve cosmetically acceptable reconstruction of the soft tissues.
Mandibular Fractures
The most common mandibular fracture, through the extracapsular part of the neck of the condyle, is usually sustained by a blow on the chin. It can be unilateral or bilateral. Examination reveals dental malocclusion, often a lateral cross-bite and absence of forward movement of the condylar head on opening the mouth. The force may have been sufficient to drive the head of the condyle backwards and cause a fracture of the squamous temporal bone. This produces bleeding and a cerebrospinal fluid (CSF) leak into the external auditory meatus.
Fractures of the ramus, angle and body will be revealed by local tenderness of the cheek and difficulty in opening the mouth. There may be surprisingly little swelling. The presence of mucosal lacerations and irregular dentition helps confirmation. Displacement is determined by the configuration of the fracture line in relation to the pull of the masticatory muscles. Mental anaesthesia may reflect damage to the inferior dental nerve.
XR
An orthopantomogram (OPT or OPG), a rotational tomogram that gives a circumferential view of the face, is especially helpful and easy to interpret. The best plain radiographs are lateral oblique, posteroanterior (PA) and Townes’ views (for the condyles).
TX
No immediate treatment is required in the ED for any of these fractures themselves. Unstable and painful fractures will require early repair; the remainder – the majority – can be referred for specialist management later. Some displaced condylar fractures can be managed conservatively with good functional results, but there is an increasing trend towards internal fixation. All patients will need analgesia and a light diet.
Temporomandibular Joint Dislocation
This may occur spontaneously (as inability to close the mouth after yawning) or result from a blow to the open mouth. It is often recurrent and is particularly common in elderly people.
XR
An OPT of the jaw is usually diagnostic. TMJ views may be requested but can be difficult to interpret. Fractures of the condyles must be excluded.
TX
Reduction can usually be achieved without general anaesthetic, but must be carried out by an experienced clinician using appropriate analgesia or sedation. The jaw is held by putting both thumbs inside the mouth along the line of the lower teeth on each side while the forefingers grasp the bone from outside. Pressure is then applied downwards and backwards by the thumbs intraorally pressing bilaterally against the angle of the jaw. Post-reduction radiographs are taken to confirm relocation although the patient is usually in no doubt. Specialist follow-up on an outpatient basis is appropriate.
Malar Fractures
The malar complex provides the bony prominence on the cheek and is commonly fractured in isolation by a blow to that area. The strong central part of the bone usually remains intact, the force being transmitted to the three buttresses. These bones then fracture or dislocate either individually or, more frequently, simultaneously (a ‘tripod fracture’):
Examination will reveal tenderness over one or more malar processes. Bony irregularity is assessed by intraoral examination behind and above the upper molars, and by careful palpation along the inferior and lateral borders of the orbit and along the line of the zygomatic arch. Diplopia may occur because of injury to the suspensory ligament or displacement and damage to the extraocular muscles. The latter is usually transient.
XR
Facial radiographs confirm the diagnosis. The most common pair of views are occipitomental projections at 10° and 30°.
TX
Once the diagnosis has been made, the patient should be referred for specialist care. If reduction and elevation of the displaced malar are required, this can be achieved relatively simply, under a short general anaesthetic on a day-case basis within the following week.
Retrobulbar Haemorrhage
This may occasionally occur after a fracture of the zygomatic complex. It causes:
- retrobulbar pain
- very marked proptosis
- diminished vision (which may quickly become permanent)
- massive facial swelling.
Middle Third Fractures
When the face is struck directly from the front, the delicate bony skeleton formed by the maxilla, palatine, nasal and ethmoid bones may be crushed and forced backwards and downwards. The nasal bones may be broken in isolation (→ below) but the other bones tend to collapse en masse. Le Fort first described the three fracture complexes that are commonly seen (→ Box 5.1).
