Facial fractures on X‑ray
Facial fractures follow assaults, falls, sport and road traffic collisions. Many significant facial injuries are now assessed directly with CT, which is the definitive test, but plain films are still used for suspected isolated injuries of the zygoma, orbit and mandible in many departments. Facial films are hard to read because of overlapping bones. The answer is a system of lines and an eye for the indirect signs: blood in the sinus, air in the orbit, and asymmetry between the two sides.
1. Views and when to image
- Occipitomental (OM) views, also called Waters views, at 15° and 30° angulation (often called OM15 and OM30, or OM and OM30). They project the petrous bones below the maxillary sinuses so the orbits, zygomas and antra are seen clearly. The two angles show the orbital floors and zygomatic arches differently.
- A lateral view is sometimes added.
- Submentovertex ("jug handle") view: shows the zygomatic arches when an isolated arch fracture is suspected.
- Mandible: an orthopantomogram (OPG or OPT) plus a PA mandible.
CT is the investigation of choice for complex midface injury, suspected Le Fort fractures, orbital injury with visual or eye movement symptoms, and any patient who also needs a head CT (use the same visit to scan the face). Plain films have little role in high-energy trauma. Nasal bone X-rays are not routinely indicated (RCR iRefer).
2. McGrigor-Campbell lines
On the OM view, trace three curved lines across the face, comparing left with right. A break, step or asymmetry suggests a fracture.
| Line | Course |
|---|---|
| Line 1 | Across the zygomaticofrontal sutures and along the superior orbital margins and the frontal sinuses |
| Line 2 | Along the upper border of the zygomatic arch, across the zygomatic body, along the inferior orbital margin and across the nasal bones to the other side |
| Line 3 | Along the lower border of the zygomatic arch, down the lateral wall of the maxillary antrum and through the condyle and coronoid process of the mandible |
Alternative systems include Dolan's lines, and the "elephant's head" outline of the zygoma and arch (the zygomatic body as the head, the arch as the trunk). Use whichever system you can apply consistently.
Pearl: always compare sides
The face is roughly symmetrical. Asymmetry in the shape of the orbital rim, the density of a maxillary antrum, or the outline of a zygomatic arch is often more obvious than the fracture line itself.
3. Indirect signs
- Fluid in the maxillary antrum: an air–fluid level on an erect film, or complete opacification of the antrum, after trauma suggests blood from a fracture of the sinus wall.
- Orbital emphysema: gas in the orbit, often seen as a dark crescent beneath the orbital roof, the "black eyebrow sign". It indicates a fracture communicating with a sinus, usually the orbital floor or medial wall.
- Soft-tissue swelling over the cheek or around the orbit.
4. Orbital blow-out fracture
A blow to the orbit from an object larger than the orbital rim (a fist or a ball) raises the pressure within the orbit, and the thinnest walls give way: the orbital floor, into the maxillary antrum, and the medial wall (the lamina papyracea), into the ethmoid sinuses. The rim itself may be intact.
- Teardrop sign: a rounded soft-tissue density hanging from the roof of the maxillary antrum, representing herniated orbital fat and sometimes the inferior rectus muscle.
- The black eyebrow sign and an antral fluid level.
- A depressed fragment of the orbital floor.
Clinical features are double vision on upward gaze (from entrapment of inferior rectus), numbness of the cheek (infraorbital nerve) and later enophthalmos. CT is the definitive test.
Red flag: the "white-eyed" blowout in children
In children the elastic orbital floor can crack and spring back like a trapdoor, trapping the inferior rectus with very little to see on imaging and little bruising. The child may have restricted upward gaze with nausea, vomiting and bradycardia from the oculocardiac reflex. This is an emergency needing urgent maxillofacial and ophthalmology review.
5. Zygomaticomaxillary complex fracture
The zygomaticomaxillary complex (ZMC) fracture, traditionally called the "tripod" fracture, follows a direct blow to the cheek. The zygoma separates from its attachments, so there are four components (hence the more accurate name "tetrapod"):
- Zygomaticofrontal suture diastasis (widening) at the lateral orbital rim;
- Zygomatic arch fracture;
- Inferior orbital rim and floor fracture;
- Lateral wall of the maxillary antrum fracture (at the zygomaticomaxillary buttress).
On the OM views, look for breaks in all three McGrigor-Campbell lines on one side, with a fluid-filled antrum. A depressed zygoma flattens the cheek. Clinically, check for infraorbital numbness, trismus (from the arch pressing on the coronoid) and diplopia.
An isolated zygomatic arch fracture, often a "V"-shaped depression, is seen best on the submentovertex view.
6. Mandible
The mandible forms a ring with the skull base at the two temporomandibular joints, so, like the pelvis, it often breaks in two places; double fractures are seen in around half or more of cases. A classic pairing is a fracture of the parasymphysis or body on one side with a fracture of the angle or condyle on the other. Once you find one fracture, look for the second.
- Common sites include the condyle, angle, body and parasymphysis; the order of frequency varies between series and mechanisms.
- Views: an OPG plus a PA mandible. The OPG can miss fractures in the symphyseal region, where the spine overlaps; the PA view helps there.
- Signs: a lucent line, a step in the lower border or in the occlusal plane, widening of a tooth socket, or overlap of fragments producing a dense line.
- A fracture running through a tooth socket is effectively open (to the mouth).
- Mandibular dislocation is usually anterior, with the condyle lying in front of the articular eminence; the mouth is locked open.
Pitfall: OPG artefacts
On an OPG the airway, tongue and soft palate create lucent and dense bands across the mandible and ramus, and the hyoid can project over the angle. A fracture line should continue through the cortex and is often accompanied by a step.
7. Le Fort fractures
Le Fort fractures are patterns of midface fracture after high-energy trauma. All three types involve the pterygoid plates, which separate the midface from the skull base. In practice they are often mixed or asymmetrical (for example Le Fort II on one side and III on the other) and are characterised with CT.
| Type | Course | Clinical result |
|---|---|---|
| Le Fort I (horizontal) | Through the maxilla just above the teeth, across the lower nasal septum and the pterygoid plates | "Floating palate": the tooth-bearing segment moves |
| Le Fort II (pyramidal) | Through the nasal bridge, the medial orbital walls, the orbital floors and the zygomaticomaxillary sutures, then the pterygoid plates | "Floating maxilla": the nose and maxilla move together as a pyramid |
| Le Fort III (transverse) | Through the nasofrontal suture, the lateral orbital walls and the zygomatic arches, and the pterygoid plates | "Floating face": craniofacial dissociation |
Le Fort II and III injuries can be associated with cerebrospinal fluid leak, airway compromise and brain and cervical spine injury.
8. Nasal bones
Nasal fractures are a clinical diagnosis. X-rays are not routinely indicated (RCR iRefer) because they do not change management, which depends on the appearance once swelling has settled. The key emergency is a septal haematoma, a soft, boggy swelling of the septum seen on examination, which needs urgent drainage to prevent cartilage necrosis.
Red flags: act now
Escalate immediately
- Airway compromise from midface or bilateral mandibular fractures (a flail anterior mandible can let the tongue fall back).
- Reduced vision, a tense proptosed eye or a relative afferent pupillary defect: possible retrobulbar haemorrhage; immediate senior and ophthalmology review.
- A child with restricted upward gaze, vomiting and bradycardia: trapdoor blowout.
- Clear fluid from the nose or ear: possible CSF leak and skull base fracture; CT.
- Septal haematoma.
- High-energy facial trauma: assess the brain and cervical spine too. See cervical spine X-ray and skull X-ray indications.
What to focus on, by role
| Role | Priorities |
|---|---|
| Medical student | The three McGrigor-Campbell lines, the teardrop sign, tripod fracture components and the mandible ring rule. |
| Nurse / ENP | Recognise the indirect signs, check eye movements and vision, and know that nasal injuries are assessed clinically. |
| Junior doctor | Know when CT replaces plain film, look for the second mandible fracture, and recognise the visual emergencies. |
| Radiographer | OM15 and OM30 positioning, submentovertex for the arch, and an OPG plus PA mandible. |
| Advanced / FRCR | Le Fort patterns and pterygoid plate involvement on CT, and subtle orbital floor fractures. |
Practise on real skull and face X-rays →
References
- Radiology Masterclass. Facial X-ray anatomy. radiologymasterclass.co.uk
- Radiopaedia. McGrigor-Campbell lines. radiopaedia.org
- Radiopaedia. Le Fort fractures. radiopaedia.org
- Royal College of Radiologists. iRefer. irefer.org.uk
- NICE NG232. Head injury: assessment and early management. nice.org.uk
For education only. Not a substitute for a formal report, senior review or your local policy. Never use this page to make decisions about a real patient.