Zygomatic Bone

Key Features & Anatomical Relations

The zygomatic bones (or cheek bones) are a pair of quadrilateral bones found along the anterolateral aspect of the cranium. They are classified as irregular bones, provide the skeletal framework for the cheeks and contribute to the formation of the orbits and viscerocranium. Each zygomatic bone includes the following bony features:

- parts: temporal, frontal, and maxillary processes;

- surfaces: lateral, temporal, and orbital surfaces, and maxillary, sphenoid, temporal, masseteric, and orbital borders;

- landmarks: orbital tubercle and the zygomatic portions of the infraorbital margin, zygomatic arch, and temporal fossa.

More information regarding these bony features can be found in the Parts, Surfaces, and Landmarks tabs for this bone.

On its corresponding side, each zygomatic bone is located:

- inferior to the frontal bone;

- anterior the sphenoid and temporal bones;

- superior to the mandible;

- lateral to a maxilla.

Each zygomatic bone articulates with the:

- frontal bone at a frontozygomatic suture

- sphenoid bone at a sphenozygomatic suture;

- temporal bone at a temporozygomatic suture;

- maxilla at a zygomaticomaxillary suture.

Ossification

Ossification of each zygomatic bone occurs at one ossification center, which appears in utero during the second months (Standring, 2016).

Variations

In some individuals:

- the zygomatic bone may be present in a bipartite condition (i.e., divided into two parts), known as the os Japonicum;

- accessory zygomaticofacial foramina may be present;

- the orbital tubercle may be absent (Tubbs, Shoja and Loukas, 2016).

Surface Anatomy

The following bony features of the zygomatic bone are relevant to surface anatomy:

- the lateral surface and the orbital, temporal and masseteric borders are all subcutaneous and easily palpated;

- the zygomatic arch, which is formed by both the zygomatic process of temporal bone and the temporal process of zygomatic bone, is palpable.

List of Clinical Correlates

- Fracture of zygomatic bone

- Osteomyelitis

- Zygomatic arch dysplasia

References

Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.

Tubbs, R. S., Shoja, M. M. and Loukas, M. (2016) Bergman's Comprehensive Encyclopedia of Human Anatomic Variation. Wiley.