Zygomatic Fractures – Review Flashcards

These question-and-answer flashcards cover anatomy, epidemiology, classification, clinical features, imaging, treatment principles, surgical approaches, fixation strategies, and complications of zygomatic (ZMC) fractures.

Which bone, with four processes, is a major determinant of facial symmetry and form?

The zygoma (zygomatic bone).

With which four bones does the zygoma articulate?

Maxilla, temporal, sphenoid, and frontal bones.

What collective term is used for fractures involving the zygoma and its sutural articulations?

Zygomatic complex or zygomaticomaxillary complex (ZMC) fracture.

Which zygomatic process is usually thickest and frequently chosen for plate fixation?

The frontal process of the zygoma.

Name two key ligaments that attach to the zygoma and help suspend the globe.

Lateral canthal ligament and Lockwood’s suspensory ligament.

Which sensory nerve exits the infra-orbital foramen to supply the cheek and upper lip?

The infraorbital nerve.

List the four principal sutures that commonly fracture in a ZMC injury.

Zygomaticomaxillary, zygomaticofrontal, zygomaticosphenoid, and zygomaticotemporal (arch) sutures.

Give three common etiological factors for zygomatic fractures.

Motor-vehicle accidents, assaults/fights, and falls (others include sports, blasts, animal attacks, industrial accidents).

Which classification describes inward & downward, inward & posterior, outward, comminuted, and isolated arch fractures?

Poswillo’s classification.

Killey’s classification distinguishes between which two broad groups of fractures?

(a) Body fractures involving the orbit, and (b) isolated arch fractures without orbital involvement.

What are the three fundamental elements of diagnosing a zygomatic fracture?

History, clinical examination, and imaging/radiologic evaluation.

State three classic visible signs of a zygomatic fracture.

Periorbital edema/ecchymosis, flattening of the malar prominence, and trismus (others include cheek paresthesia, subconjunctival hemorrhage).

Which bedside test differentiates temporary from permanent diplopia?

The forced duction test.

Which standard radiographic view (OM) is often used first for suspected ZMC fractures?

Waters (occipitomental) view.

What overarching goal guides treatment of zygomatic complex fractures?

Accurate reduction of the zygomatic articulations to restore normal facial contour and function.

List the broad treatment options in order of invasiveness for ZMC fractures.

No treatment, indirect reduction (with or without fixation/support), and direct reduction with fixation.

Give one absolute indication for surgical intervention in a zygomatic fracture.

Visual compromise (others: extra-ocular muscle dysfunction, globe displacement, displaced/comminuted fractures, restricted mandibular movement, infra-orbital nerve dysfunction).

State two specific aims of surgery in ZMC fracture management.

Restore normal facial contour and relieve pain (others: precise anatomic reduction, correct diplopia, stable fixation, free mandibular movement, decompress infraorbital nerve).

Name two extra-oral surgical approaches commonly used to access the zygoma.

Coronal (bicoronal/hemicoronal) and Gillies temporal approaches (others: lateral eyebrow, upper eyelid, infra-orbital, subciliary, trans-conjunctival).

Which intra-oral approach gives direct access to the zygomatic arch?

Keen’s transoral lateral maxillary vestibular approach.

Which classic indirect reduction method employs a temporal incision and Rowe elevator?

Gillies temporal fossa approach.

For an isolated zygomatic arch fracture, is rigid internal fixation usually required?

No; closed reduction (Gillies, Keen) suffices because muscles and fascia splint the arch.

How many fixation points are recommended when reduction accuracy is uncertain in complex ZMC fractures?

Four-point fixation.

List the four anatomical sites typically plated in 4-point fixation of a zygoma.

Zygomaticofrontal suture, infra-orbital rim, zygomaticomaxillary buttress, and zygomatic arch.

According to plate-fixation principles, how many screws should be placed through a plate on each side of a fracture?

At least two screws on each side.

Which metal is preferred for plates and screws to minimize CT scan scatter?

Titanium.

What serious ocular complication involves bleeding behind the globe after surgery or trauma?

Retrobulbar haemorrhage.

Injury to which nerve commonly causes cheek and upper-lip paresthesia after ZMC fractures?

The infra-orbital nerve.

What term describes posterior displacement of the globe producing a ‘sunken’ eye?

Enophthalmos.

Permanent diplopia usually results from what underlying problem?

Paralysis or entrapment of an extra-ocular muscle (often inferior rectus) in the fracture line.

What temporary intra-antral measure can support a reconstructed orbital floor or ZMC fracture?

Maxillary antral packing/balloon (e.g., Penrose drain, gauze, Silastic balloon).

Why does a displaced zygomatic arch often cause trismus?

It impinges on the coronoid process or temporalis muscle, restricting mandibular movement.

Özyazgen et al. label isolated zygomatic arch fractures as which type?

Type I fractures.

Give one instrument commonly used to elevate a depressed zygoma in the Gillies approach.

Rowe zygomatic elevator (others: Gillies elevator, Dingman elevator).

Which imaging modality provides the most detailed assessment of ZMC fractures, including orbital walls?

Computed tomography (CT) with 3-D reconstruction.

Which quick bedside test moves a finger in nine gaze positions to detect diplopia?

Finger-gaze test.

Which ligament attaches to Whitnall’s tubercle and maintains lateral canthal support?

The lateral canthal ligament.

Name two widely cited classification systems for zygomatic fractures other than Poswillo.

Knight & North and Rowe & Williams (others: Ellis, Fuji & Yashimiro, Manson, Spissel & Schroll).

What are three long-term complications that can follow ZMC fracture repair?

Persistent diplopia, enophthalmos, malunion (others: infra-orbital nerve disorders, sinusitis, implant infection, ankylosis to coronoid).