The zygomatic bone, commonly known as the cheekbone, is a paired, irregularly shaped structure that plays a considerable role in the anatomy of the face. It gives the cheek its characteristic prominence and serves as a structural foundation for surrounding tissues. The bone connects with several other facial and cranial bones, forming part of the lateral wall and floor of the eye socket, which protects the delicate orbital contents. Because of its prominent position, a zygoma fracture is considered a serious midface injury that can affect the appearance and function of the eye, jaw, and sensory nerves.
Common Ways Zygomatic Fractures Occur
Fractures of the zygomatic bone typically require significant kinetic force because the bone is robust and serves as a structural buttress for the midface. Due to its prominent position, it is particularly vulnerable to direct impact, making it the second most frequent facial fracture after nasal bone injuries. The most common causes involve blunt force trauma, with physical altercations often cited as the leading mechanism of injury, particularly in younger adults.
Motor vehicle accidents are another major cause, often resulting in more complex fractures due to the high-velocity impact involved. Other common mechanisms include accidental falls, especially in older patients, and sports-related injuries. The location and severity of the fracture depend on the direction of the force; a direct blow may result in an isolated arch fracture, while a comprehensive blow can lead to a complex fracture involving the eye socket and upper jaw.
Immediate Signs and Impairments
A broken cheekbone presents with visual signs and functional limitations that manifest rapidly after the injury. One of the most noticeable signs is rapid, extensive swelling and bruising around the eye and cheek area. This periorbital bruising often resembles a “black eye” and can make functional assessment challenging in the acute phase.
If the fracture is displaced, the normal prominence of the cheek can appear flattened or sunken, known as malar flattening. A palpable “step defect” may be felt along the infraorbital rim, the lower bony border of the eye socket, indicating a misalignment of the fractured segments. Bleeding from the nose, called epistaxis, can occur if the fracture extends into the maxillary sinus lining.
Functional impairments are frequently experienced due to the zygoma’s close proximity to nerves and the eye socket. Numbness or a tingling sensation (paresthesia) is common, often affecting the cheek, upper lip, side of the nose, and upper teeth. This occurs because the infraorbital nerve, which provides sensation to these areas, passes near the fractured bone and can be compressed or damaged.
Vision can be affected if the fracture involves the orbital floor, leading to impaired eye movement and double vision, known as diplopia. The muscles that control eye movement can become entrapped by the fractured bone segments, or the eyeball itself may slightly sink (enophthalmos) due to a break in the orbital floor. Additionally, patients may find it painful or difficult to open their mouth fully, a condition called trismus, which is caused by the displaced bone fragment impinging on the movement of the lower jaw.
When Medical Confirmation is Necessary
Any suspected facial fracture, particularly one accompanied by visual changes or sensory loss, requires immediate professional medical assessment, usually in an emergency room setting. Confirmation of a zygomatic fracture requires specialized imaging to accurately map the extent of the damage, going beyond a physical examination. While traditional X-rays were historically used, they are now largely considered obsolete for complex facial trauma due to insufficient detail.
The gold standard diagnostic tool is a computed tomography (CT) scan, which provides detailed visualization of the fracture lines, displacement, and involvement of adjacent structures. A CT scan allows doctors to assess if the fracture has compromised the eye socket, a significant factor in determining the need for surgery. The scan also helps determine the degree of bone fragment rotation and displacement, often measured in millimeters to guide treatment decisions.
Options for Repair and Healing
The management of a broken cheekbone depends heavily on the severity of the fracture and whether it has caused functional or aesthetic deficits. Fractures that are minimally displaced and do not cause functional issues, such as double vision or severe numbness, are often managed non-surgically. This conservative approach typically involves pain control, a soft diet, keeping the head elevated to reduce swelling, and close monitoring to ensure proper healing.
Surgical intervention is generally recommended for fractures that are significantly displaced, cause functional impairments like vision problems, or result in noticeable facial asymmetry. The goal of surgery is to restore the bone to its correct anatomical alignment to recover facial contour and function. This procedure is often performed using Open Reduction and Internal Fixation (ORIF), where the surgeon accesses the fracture site, manually repositions the bone fragments (reduction), and secures them using small titanium plates and screws (internal fixation). For complex fractures involving the eye socket, the orbital floor may also be reconstructed during the ORIF procedure. The timing of surgery is often scheduled after the acute swelling has subsided, typically within seven to fourteen days post-injury, but before the bone begins to set in a displaced position. Healing timelines vary, but most patients require a period of restricted activity, and any residual numbness may take several months to a year to resolve.