Facial fractures are common injuries and sporting activities are a common source of them. This was well illustrated by a well chronicled facial injury sustained recently in the NBA. Oklahoma City’s Russell Westbrook was injured in a game last Friday in Portland when his teammate’s knee collided into the right side of his face in the last minute of the game. This left an immediate imprint in the side of his face between the eye and the ear. The next day he had surgery to repair a ‘cheekbone’ fracture.
Understanding the anatomy of the cheek bone, technically known as the zygomatico-orbital complex, will explain the specific type of facial fracture this NBA player sustained. The distinct imprint on the side of his face was caused by a zygomatic arch fracture. This is the very thin stick of bone that goes from the main body of the cheekbone (zygoma) back to its attachment to the temporal bone in front of the ear. It is like an arched bridge that spans the cheek and skull to let the large temporal muscle go underneath it.
Because the zygomatic arch is so thin, it is one of the most easily fractured bones on the face. But it requires a direct blow to the height of the arch to create a displaced fracture. It usually fractures inward like a V with two collapsing spans of a bridge. But it can also be a comminuted type zygomatic arch fracture where it breaks into multiple pieces and the entire ‘span of the bridge’ falls inward.
Repair of a displaced zygomatic arch fracture is unlike just about every other facial fracture other than that of the nasal bones. It is located in an area where direct surgical access is impossible due to branches of the facial nerve. Without direct access it is not possible to rigidly fix the fracture with plates and screws. (at least not very easily) Thus zygomatic arch fractures are repaired from a remote incision in the temporal scalp and are elecated back up into position off of the temporalis muscle.
Zygomatic arch fracture repairs are, by definition, unstable since they are not rigidly fixed back into place. This is why you will usually see some type of protective device over the side of the face to prevent secondary inward displacement while it heals.
Dr. Barry Eppley
Indianapolis, Indiana