Tripod Fractures

Tripod fractures are a set of fractures of the zygoma and are also known as  zygomaticomaxillary complex fractures. These are termed tripod fractures since the fracture involves the three buttresses of the zygoma - the frontozygomatic suture, zygomaticomaxillary sutures, and the zygomaticotemporal suture. Occasionally, a fourth suture may be involved - the zygomaticosphenoid suture. The zygomaticomaxillary complex can be considered as a quadripod structure because of its relationship to the frontal bone, maxilla, temporal bone, and skull base. Tripod fractures should be distinguished from isolated fractures of the zygomatic arch. Tripod fractures demonstrate variable severity manifested by their degree of zygoma fragmentation and sutural separation. Surgery is performed to reestablish the correct positioning of the malar prominence.

Moderate and severe tripod fractures frequently extend to the infraorbital foramen and can result in infraorbital nerve injury. Moderate and severe tripod injuries are also seen in association with orbital floor or blowout fractures.

In severe tripod fractures, the zygoma fragment can be displaced posteriorly to the coronoid process, often preventing jaw closure. Severe tripod fractures may also have a fracture line extending posteriorly, disrupting the temporomandibular joint.

	Mild Tripod
	Moderate Tripod
	Severe Tripod