return to: Facial Fracture Management Handbook
by Dr. Gerry Funk
Malar Complex Fractures
Anatomy and Mechanism of Injury
The term malar complex fracture refers to a fracture which in its classic form primarily involves the suture lines of the zygomatic bone.
This fracture has in the past been called a tripod fracture although that term has fallen out of use with the appreciation that this is really not a tri but rather a tetrapod fracture. In the classic malar fracture, the zygomatic bone is displaced downward with resultant disruption of the zygomaticofrontal, sphenozygomatic, zygomaticotemporal and zygomaticomaxillary sutures. The zygomaticomaxillary suture is disrupted at both the inferior orbital rim and laterally in the region of the zygomaticomaxillary buttress. Although it is given little attention, reduction of the sphenozygomatic suture line is often crucial to the proper anatomic reduction of malar fractures because it defines the internal and external rotational position of the fragment.
Most malar fractures result from a medial and downward force impacting on the malar eminence which is an easy target in situations of interpersonal conflict.
Physical Exam
Head and neck trauma exam with special attention to:
1. Visual acuity, extraocular motion, enophthalmos
2. Facial symmetry, orbital rim step off's
3. Decreased maximal incisor opening may result from impaction of the zygomatic arch into the coronoid process of the mandible.
4. Numbness in the cranial nerve V2 distribution.
Emergency Management
In most isolated malar complex fractures the patient is ambulatory and not in life or limb threatening distress. The main emergency intervention in these injuries is to be sure that there has been no associated ocular injury. If any significant visual changes exist a CT scan should be done emergently to exclude the possibility of bony fragments impinging on the globe or optic nerve. Most patients will be discharged from the emergency room to follow up in several days for definitive repair. All patients with malar fractures should be given a 7 day course of an anti staph and strep antibiotic due to the possibility of blood in the maxillary sinus becoming infected.
Radiographic Work Up
The radiographic work up for malar fractures to some extent depends on the treating institution and whether or not evidence exists for an associated orbital floor fracture. For minimally or noncomminuted malar fractures with no evidence of orbital floor involvement, a facial series including a Waters, submentovertex and orbital views probably defines the fracture as well as a CT. In most institutions however, the standard of care would dictate that the managing surgeon obtain a CT scan. One reason for this is that if coronal views of the orbit demonstrate no orbital floor fracture, the orbital floor does not need to be explored. At this institution we obtain a CT scan on all malar fractures. The views requested should be fine cut, bone window, axial and coronal cuts of the midface and orbits. If a coronal CT can be done that is preferable to sagittal reconstructions.
Definitive Management
In rare cases patients present with malar fractures evident only on X-rays or CT scans, the actual fractures of which are greenstick in nature and no cosmetic or functional deformity exists. In these cases simply placing the patient on a soft diet to minimize masseter pull on the zygoma is the preferred intervention. In theory masseter pull could cause the malar fragment to settle and this is frequently stated to be a concern. I have never seen that occur with a greenstick fracture.
In the more common situation the main body of the zygoma is displaced inferiorly and a variable amount of comminution is present. These types of fractures are best managed with some form of internal fixation. Numerous techniques are available for internal fixation of malar fractures. Interosseous wire fixation at the inferior orbital rim, zygomaticofrontal suture and zygomaticomaxillary buttress was used frequently until miniplates and screws became popular. In selected cases a transcutaneously placed "K" wire may be drilled through the main malar fragment, after it is elevated, and then secured into the palate. The "K" wire is then cut off at skin level and left in place for 6 weeks to stabilize the fracture (Matsunaga et al. 1977). This technique is satisfactory only for the very rare cases in which there is no significant comminution of the main malar fragment or orbital floor involvement.
The technique most frequently used at this institution is fixation with mini or micro plates. Plates are most frequently placed at the zygomaticofrontal and zygomaticomaxillary sutures and at the inferior orbital rim if needed. Exposure is via a unilateral sublabial incision and brow incision. If the orbital floor or inferior orbital rim are significantly involved a subciliary or transconjunctival approach is also used.
References
Matsunaga, R.S., Simpson, W., Toffel, P.H. Simplified protocol for treatment of malar fractures. Arch. Otolaryngol. 103: 535-38, Sept. 1977.