Zygomatic Fractures

 Updated 3/2017 --photos and all links removed as many no longer active and it was easier than checking each one.

I wish I was good at facial fractures. I am not. There wasn't enough volume of these cases when I was a plastic surgery resident, so I came into private practice not feeling comfortable with them. Then there wasn't much volume in the early years of my practice to gain a comfort level with them. Later I began to avoid them. When EMTALA came along, I decided to withdraw my facial fracture privileges from the hospitals where I continue to do unassigned ER call. I felt this was my only way to protect the patient from my lack of skill or insufficient skill or however you want to put it. I continue to sew up the facial lacerations, but if there is a fracture associated with the laceration the ER now has to call someone else.

Before EMTALA, I would have sewn up the lacerations and gotten the appropriate X-rays (now CT scans). Then the next day, I would have called someone else--either plastic surgeon, ENT, or oral maxillary surgeon to take over the care. They wouldn't have been called in the middle of the night, but during the day time hours. It would have been okay. No one would have felt like I was "dumping" on them.

Still I continue to ready the journal articles about facial fractures. As you can see from the second reference below, there has been a recent supplement volume (very comprehensive) dedicated to these fractures. Since I learn by writing these posts, I thought I would try to tackle this topic over several posts. It still won't improve my OR skill with them, but it might clarify some of my understanding of them. I hope you will indulge me and maybe learn with me.

There is a nice basic summary at eMedicineHealth on facial fractures.
ZYGOMATIC FRACTURES

The zygoma is the bone that is known as the cheek bone. It articulates with the maxilla, the temporal bone, the sphenoid bone and the frontal bone. It forms the prominence of the cheek and part of the lateral wall and floor of the orbit (eye socket). It is this prominence that makes it so susceptible to trauma.

The mechanism of injury usually involves a blow to the side of the face from a fist, object (like a baseball), or secondary to motor vehicle accidents. Studies show that 80% of these injuries are due 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 (the places where the different bones meet/join) are most often the result of high-velocity motor vehicle accidents.

Over the years, isolated fractures of the zygoma have been called zygomatic, tripod, or orbitozygomatic fractures. The last term is the preferred. Here in the United States, zygomatic fractures are the second most common fracture of the facial bones. The first being nasal bone fractures. As many as 5% of these patients have associated ophthalmic injuries. Males are afflicted more commonly than females by a 4:1 ratio. Most cases occur in young patients in their second to third decades of life.

DIAGNOSIS
Physical signs and symptoms of zygoma fractures include

• Subconjunctival hemorrhage and periorbital ecchymosis are seen in as many as 50% of patients.
• Disturbance of sensation in the region of the infraorbital nerve
• Palpable step-offs in the upper lateral orbital rim, inferior orbital rim, and upper buccal sulcus
• Emphysema within the orbit or overlying soft tissues of the cheek
• Trismus -- is difficulty with mastication and can occur because of masseter spasm or bony impingement of the coronoid process.
• Malposition of the globe and /or diplopia (double vision)--Diplopia may be secondary to change in pupillary alignment or to entrapment of the inferior rectus muscle by the orbital wall fracture. Patients with entrapment may complain of diplopia on upward gaze.
• Globe injury needs to be ruled out as well. Traumatic optic neuropathy is a complication that has been reported in about 2 to 5 percent of severe facial trauma.

Facial swelling is almost always substantial by the time the patient is seen by the surgeon. This tends to minimize the degree of deformity, masking the cheek malposition. The swelling may take 2 weeks to resolve so that the patient (and surgeon) can visually (not by CT scan) appreciate the true deformity. However, the best result is obtained if the reduction and stabilization of the fracture is done within the first 2 weeks after the injury. So the surgeon has to be good at 3-D visualization to fully appreciate the bone structure injury and to optimally reduce the fracture while the soft tissue swelling is still present.

SECONDARY DEFORMITIES
These are deformities that occur because of untreated or mistreated fractures. They are not uncommon (unfortunately). They include

• Underprojection of the cheek and a wide face.
• Overprojection is possible, but not as common as the first.
• Globe malposition--either enophthalmos (a sunken eye, is the most common) or exophthalmos (eye protrudes out of the socket).
• Soft-tissue deformities from inadequate suspension after extensive surgical exposure. Cheek ptosis, inferior displacement of the lateral canthus, temporal hollowing, and lower lid ectropion are the most common.

IMAGING

Patients with suspected facial trauma should initially be evaluated with a complete craniofacial CT scan. A full facial analysis from the top of the head through the mandible with 1.5 mm axial cuts will allow coronal reformatting without additional scanning. Sagittal reformatting is useful in assessing the effect of a complex orbital fracture on the inferomedial bulge of the orbital floor. If the patient presents with neurologic compromise (head injury or intoxication) and cannot comply with a complete physical examination, it is prudent to obtain a complete scan at the time that the head CT scan is obtained.

CLASSIFICATION

Several classifications of zygomatic fractures have been described in the literature, but none seem to be universally accepted. Most classifications are based on the degree of comminution, whether the fracture is simple or compound, and the site of the fractures. In 75% of cases, these fractures are displaced inferiorly, medially, and posteriorly. The classification system by Knight and North identifies six groups:

• Undisplaced -- require no therapy, see Medical Care below
• Arch fractures -- considered a stable fracture
• Unrotated body fractures -- can usually be treated by closed reduction
• Medially rotated body fractures -- considered an unstable fracture
• Laterally rotated body fractures -- considered a stable fracture
• Complex fractures having additional fracture lines across the zygomatic body

MEDICAL CARE

The literature indicates that 10-50% of all zygomaticomaxillary complex fractures require no surgical intervention. This is suitable for fractures that are nondisplaced or minimally displaced or where systemic status precludes operative intervention.

• Stable, nondisplaced fractures may be observed weekly for healing.

• Avoidance of nose blowing is mandatory in the medical care of these patients. The disrupted orbital walls can allow air to be forced into the retrobulbar space and cause pain and visual loss. This avoidance of nose blowing should last for several weeks to a couple of months.
• Avoid sleeping face down or with pressure on the affected side of the face

• The routine use of systemic antibiotics for isolated zygomatic arch fractures generally is not recommended.
• Patients commonly are placed on a soft diet for six weeks. A dietary consultation may be warranted.
• All contact sports and most strenuous activity also should be avoided for several weeks.

BASIC PRINCIPLES OF SURGICAL REPAIR

The aims of treatment of zygomatic complex fractures include the restoration of normal facial form, normal sensory nerve function, normal globe position, and normal masticatory function. Indications for repair of zygomatic complex fractures include displacement or instability of the fracture, mechanical restriction of mandibular movement (chewing), alteration in facial contour, globe dystopia, enophthalmos, diplopia, or sensory nerve deficit.

Generally, it is suggested to avoid surgery during times of maximum edema but prior to the adhesion of displaced bony fragments and scarring of soft tissues into bony defects. Most surgeons advise surgical intervention prior to the formation of dense scar tissue. As a general guideline, surgery should be undertaken prior to 3 weeks postinjury, optimally prior to 2 weeks postinjury.

Isolated arch fxs and minimally displaced noncomminuted fxs

• The Gilles approach may be used. It can be done under either local anesthesia with sedation or under general anesthesia. A vertical incision is made in the temporal hairline, and the elevator is then tunneled underneath the temporalis fascia, keeping in mind the superficial temporal artery branches and the temporal division of facial nerve, which is nearby. Then lateral pressure with superior anterior rotation is exerted to pop the fracture back in place.

Unstable or potentially unstable fractures

• A more aggressive approach using open-reduction techniques and rigid stabilization with plating systems (eg, Synthes or Leibinger) is the standard of care today. This approach provides direct access to the frontozygomatic suture, orbital floor, and infraorbital rims.

• Precise reconstruction with rigid internal fixation of the zygoma at 2 or 3 points (across the frontozygomatic suture, the inferior orbital rim, and the lateral midfacial buttress) is needed to counter the force of the masseter muscle. The orbital contents can be supported as for simple orbital floor fractures.

COMPLICATIONS of Surgical Repair
Many of these are included in the list of secondary deformities listed above.

• Diplopia has been quoted to occur between 3.4 and 8 percent. It is most often thought to be secondary to extraocular muscle contusion, swelling, and occasionally entrapment as well. As a result, forced duction test is recommended prior to closure to make sure there is no muscle entrapment, and when in doubt CT can be used.
• Anesthesia/dysesthesias, usually in the infraorbital nerve region, has been reported between 0.4 and 11.6 percent postoperatively as well; however, usually they resolve on their own, but if they last more than three to twelve months, then one may suspect impingement as a possible cause.
• Enophthalmos, as you see in this picture here, is most often secondary to inadequate fracture reduction. This has been reported to occur anywhere between 1 and 23 percent postoperatively. If enophthalmos is noted during the early postoperative period, reoperation is a viable option. Most often, the enophthalmos is thought to be due to the fact that the zygoma has been fixed too far posteriorly and laterally; however, in the late postoperative period, reoperation will often require osteotomy (re-fracture).
• Complications related to hardware eventually requiring removal is also not uncommon. The most commonly cited reason for needing removal is palpability, specifically in the infraorbital rim and the frontal zygomatic suture region. In this study, they also saw an isolated case of plate fracture.
• The rare complication of sudden onset blindness resulting from retrobulbar hemorrhage following reduction of even simple zygomatic fractures means that in some instances, this procedure may be unsuitable for outpatient surgery. This serious complication, although rare (0.3% of treated zygomatic fractures), is potentially reversible upon early recognition of the symptoms and signs of retrobulbar hemorrhage (eg, pain, proptosis, loss of vision, decreased motility). If the surgeon suspects a retrobulbar hemorrhage, a lateral canthotomy and cantholysis should be performed as soon as possible. This should be completed at the bedside if the patient has visual compromise and is not near the operating suite.

REFERENCES
Facial Trauma, Zygomatic Complex Fractures by Zachary Segal MD, et al--eMedicine Article
Craniofacial Trauma; Supplement to Plastic & Reconstr Surgery, Vol 120, No 7, Suppl 2, Dec 2007; Larry H Hollier, Jr MD and James F Thornton MD
Orbital Fracture, Zygomatic by Stuart R Seiff, MD, et al--eMedicine Article
Facial and Mandibular Fractures by Michael L. Richardson, M.D., University School of Medicine
Blindness after Reduction of Facial Fractures; Plastic & Reconstructive Surgery. 102(6):1821-1834, November 1998; Girotto, John A. M.D.; Gamble, William Bryan M.D.; Robertson, Bradley M.D., D.D.S.; Redett, Rick M.D.; Muehlberger, Thomas M.D.; Mayer, Mike M.D.; Zinreich, James M.D.; Iliff, Nicholas M.D.; Miller, Neil M.D.; Manson, Paul N. M.D.
Zygomaticomaxillary Complex Fracture by Tang Ho, M.D.;
October 7, 2004--Grand Rounds Baylor College of Medicine
Manual of Internal Fixation in the Cranio-Facial Skeleton: Techniques By Joachim Prein