The Anatomy of the Zygomatic Bone

The zygomatic bones are more commonly known as the cheekbones. These bones are located just below each eye and extend upward to the outer side of each eye. The zygomatic bones join with several other bones of the face, including the nose, jaw, portions of the eye, and bones just in front of the ears.

The zygomatic bone consists of cartilage when a fetus is in utero, with bone-forming immediately after birth. Due to its size and function in joining many facial bones together, underdeveloped zygomatic bones cause significant issues related to the construction of the face. The most significant condition associated with the zygomatic bones is a fracture.

Anatomy

The zygomatic bone is somewhat rectangular with portions that extend out near the eye sockets and downward near the jaw. The front portion of the bone is thick and jagged to allow for its joining with other bones of the face. This thickness also allows the bone to remain strong and sturdy to protect the more delicate features of the face. Other portions of the zygomatic bone include joints near the jaw, near the ears, and near the forehead and skull.

Near the skull, the articulations (where two bones come together) are not as thick. This allows for the structure of the skull to take over as the main protector of the brain and other underlying structures. There is also a tunnel within the zygomatic bone called the zygomaticofacial foramen which allows for the passage of integral veins and arteries through the face.

Anatomical Variations

Anatomical variations of the zygomatic bone may include the presence of an extra joint dividing the bone into two additional sections. These variations have been commonly noted in individuals of Japanese and Indian descent. Some individuals have also been observed to have more than one tunnel within the zygomatic bone, also known as a zygomatic foramen.

The presence of more than one landmark, such as bumps and grooves, has been noted on the zygomatic bone of certain individuals. Other variations include differences in where the zygomatic bone meets the jaw bone and the forehead, along with longer landmarks at the site of these joints.

Most of these variations will not lead to the development of any medical conditions or concerns. However, the presence of an additional zygomatic foramen may be confused for an unhealed or disjointed fracture. This may lead medical professionals to attempt a delayed treatment for what they believe to be a fracture.

Function

The zygomatic bone functions as a structure which joins the bones of the face while protecting the arteries, nerves, veins, and organs which lie below the surface. The arches of the zygomatic bone provide a person’s cheeks with the structure to fill out the face.

The zygomatic bone itself has no ability to move, as it is a stationary bone which allows it to function mainly for protection. However, the lower portion of the zygomatic bone which joins with the jaw bone assists in providing movement to the jaw bone. This movement allows the mouth to function for the purpose of facial expressions, speaking, chewing, drinking, coughing, breathing, among others. The stability the zygomatic bone provides also allows for motion associated with other bones connected to the zygomatic bone.

Additionally, the grooves and indentations of the upper zygomatic bone provide space for muscles to insert in the forehead and upper portion of the skull. This allows the zygomatic bone and other facial bones to connect with the upper portion of the skull.

Associated Conditions

The most common condition associated with the zygomatic bone is a fracture. A fracture to the orbital floor, the portion of the zygomatic bone which is attached to the eye, also has an impact on the function of the zygomatic bone. This type of fracture is called a blowout and can cause a fracture to the zygomatic bone, displace the upper portion of the zygomatic bone which articulates with the skull, and can cause a deeper fracture to the eye socket. Jaw fractures can also impact the lower portion of the zygomatic bone, causing difficulty chewing, speaking, and other functions associated with the mouth.

Vision problems may be associated with orbital fractures, along with muscle spasms to the nearby facial muscles. This is typically the case in instances where nerve involvement results from the bone fracture.

Rehabilitation

Fractures to the zygomatic bone are diagnosed through an X-ray. Patients are instructed not to blow their nose or perform any large facial movements which may cause pain or further disturb the fracture. Depending on the severity of the fracture, the zygomatic bone may be monitored through home health and treated with antibiotics to prevent or treat infection.

More serious zygomatic fractures may result in inward displacement of the eyeball, persistent double vision, or cosmetic changes. These instances require surgery to apply fixators to the bones and minimize complications.

The absence of cosmetic changes following a facial injury in children can result in a delayed diagnosis. White-eyed blowouts are orbital fractures which occur in children and result in a presentation similar to that of a concussion. This may include nausea, vomiting, and cognitive changes. Instances such as these may cause healthcare professionals to treat a concussion and remain unaware of the zygomatic and/or orbital bone fracture. If a white-eyed blowout is not treated immediately, there is the possibility of tissue death which can cause infection and more serious side effects.