Location of the Zygomaticotemporal Foramen
The foramen is located on the temporal surface (Facies temporalis) of the paired zygomatic bone (Os zygomaticum). This surface faces the infratemporal fossa.
The zygomatic bone has three surfaces: lateral, orbital, and temporal. The orbital surface (Facies orbitalis), which contributes to the formation of the lateral wall and floor of the orbit, contains the zygomaticoorbitale foramen (Foramen zygomaticoorbitale).
From the zygomaticoorbitale foramen, a canal runs within the bone and branches into two pathways. One opens on the lateral surface as the zygomaticofacial foramen (Foramen zygomaticofaciale), and the other opens on the temporal surface as the zygomaticotemporal foramen (Foramen zygomaticotemporale).
Contents of the Zygomaticotemporal Foramen
The zygomaticotemporal nerve (N. zygomaticotemporalis) exits through the zygomaticotemporal foramen.
The pathway and origin of this nerve are as follows:
- Origin: The zygomaticotemporal nerve is a branch of the zygomatic nerve (N. zygomaticus).
- Origin of the zygomatic nerve: The zygomatic nerve branches off the maxillary nerve (N. maxillaris), which is the second division of the trigeminal nerve (CN V).
- Course in the orbit: The zygomatic nerve enters the orbit via the inferior orbital fissure (Fissura orbitalis inferior) alongside the infraorbital nerve and vessels.
- Intraosseous course: The nerve enters the zygomaticoorbitale foramen, where it divides into branches within the bony canal. The zygomaticotemporal branch exits through the Foramen zygomaticotemporale.
Topography and Relations
The zygomaticotemporal foramen establishes a communication pathway between the orbit and the temporal fossa (Fossa temporalis).
- Temporal fossa is bounded superiorly by the superior temporal line, inferiorly by the zygomatic arch and infratemporal crest, anteriorly by the zygomatic process of the frontal bone and the temporal surface of the zygomatic bone, and posteriorly and medially by the greater wing of the sphenoid bone.
- Lateral wall of the orbit (Paries lateralis) is formed by the zygomatic process of the frontal bone, the orbital surface of the greater wing of the sphenoid bone, and the orbital surface of the zygomatic bone.
Clinical Significance in Trauma
Fractures of the zygomatic bone and zygomatic arch account for 6% to 20% of all facial bone trauma cases.
Common causes include blunt facial trauma, falls, motor vehicle collisions, occupational injuries, and sports accidents. On radiographic imaging, fracture lines may be identified in the region of the frontozygomatic suture and the zygomatic arch.