Zygomatic Complex Fractures

Updated: Jul 05, 2023
  • Author: Stuart Seiff, MD, FACS; Chief Editor: Hampton Roy, Sr, MD  more...
  • Print
Overview

Background

The zygomatic bone occupies a prominent and important position in the facial skeleton. The zygoma forms a significant portion of the floor and lateral wall of the orbit and forms a portion of the zygomatic arch, otherwise known as the malar eminence, which plays a key role in the determination of facial morphology. Fractures of the zygomatic complex occur because of the rotation of the zygoma associated with the disarticulation of the zygomatic bone at the zygomaticofrontal suture (along the lateral orbital rim), the zygomaticomaxillary suture (medially), and along the zygomatic arch to the temporal bone (see below). [1, 2]

The zygoma forms a firm buttress for the orbit and The zygoma forms a firm buttress for the orbit and typically fractures at its sutures.

Anatomically, the zygomatic bone contains foramina that allow for the passage of the zygomaticofacial and zygomaticotemporal arteries and corresponding nerves of the second division of the trigeminal nerve that supply sensation to cheek and anterior temple. Similarly, the infraorbital nerve courses the floor of the orbit and exits the infraorbital foramen or notch. Consequently, fractures of the zygomatic arch can lead to hypoesthesia in the corresponding dermatome. Muscle attachments along the zygomatic arch include the origin of the masseter, the zygomaticus major, and some fibers of the temporalis fascia. The Whitnall tubercle, which serves a critical role in the maintenance of eyelid contour as the attachment site for the lateral canthal tendon, is located on the zygomatic bone 2 mm behind the lateral orbital rim. [3]

Next:

Pathophysiology

The zygoma is the main buttress between the maxilla and the skull, but, in spite of its sturdiness, its prominent location makes it prone to fracture. The mechanism of injury usually involves a blow to the side of the face from a fist, from an object, or secondary to motor vehicle accidents. Moderate force may result in minimally or nondisplaced fractures at the suture lines. More severe blows frequently result in inferior, medial, and posterior displacement of the zygoma. Comminuted fractures of the body with separation at the suture lines are most often the result of high-velocity motor vehicle accidents.

In general, displaced fractures involve the inferior orbital rim and orbital floor, the zygomaticofrontal suture, the zygomaticomaxillary buttress, and the zygomatic arch. However, occasionally, a direct blow to the arch results in an isolated depressed fracture of the arch only. [3]

Previous
Next:

Epidemiology

Frequency

In the United States, zygomatic fractures are the second most common fracture of the facial bones following nasal bone fractures. [4] Studies from countries outside the United States found zygomatic complex fractures to be the most common fracture site in patients with maxillofacial trauma. [5]

Mortality/Morbidity

Patients with zygomatic fractures frequently have associated ophthalmic injuries, especially in the setting of combined zygomatic and orbital floor fractures. [6]

Sex

Males experience zygomatic fractures more commonly than females, and a higher proportion of male patients requires surgical intervention. [7]

Age

Most cases of zygomatic complex fractures occur in young patients in their second to third decades of life, with the exception of fractures due to accidental falls, which mainly are seen in older patients. [7, 8]

Previous
Next:

Prognosis

Displaced fractures can lead to changes in globe position and facial contour if not properly realigned. Associated ophthalmic and intracranial injuries may occur and may carry separate prognostic considerations.

Postoperative complications include ectropion, epiphora, [9] plate exposure, and wound infections, potentially requiring removal of implanted material. [10] Case reports have also described postoperative orbital hemorrhage, which can lead to permanent blindness in the affected eye. [11]

Indicators of favorable outcome include bony union, absence of skeletal or soft tissue deformity, and a normal range of mandibular movement.

Previous
Next:

Patient Education

It is essential to instruct patients to avoid forceful nose blowing. The disrupted orbital walls can allow air to be forced into the retrobulbar space, causing orbital emphysema, which may lead to pain and visual loss. Advise patients to call the surgeon at any time if orbital bleeding is suspected.

Intermittent application of ice packs to the area of the fracture in the first 3-4 days after injury may aid in alleviating pain and edema.

For excellent patient education resources, visit eMedicineHealth's First Aid and Injuries Center. Also, see eMedicineHealth's patient education article Facial Fracture.

Previous