Resident Manual of Trauma to the Face, Head and Neck

1. Longitudinal Injuries Longitudinal injuries are much more common and account for 70–90 percent of fractures. They follow a course through the external auditory canal (EAC) and TM, progressing along the axis of the petrous apex, following the path of least resistance, which often involves aerated regions, foramina, and suture lines. Longitudinal injuries classically result from a blow to the temporal parietal region. They are frequently associated with a CHL, and may have an associated facial nerve injury in the perigeniculate region. Figure 6.2 illustrates the path of a longitu- dinal and transverse fracture relative to the long axis of the petrous bone. Figure 6.3 represents the radiologic appearance of a longitudinal fracture. This patient sustained a fracture in a motor vehicle accident and had complete facial paralysis, requiring decompression.

Figure 6.2 Superior view of the left temporal bone in isolation. This image illustrates the long axis of the temporal bone and the course of longitudinal (red dashed line) and transverse (blue-dashed line) patterns of fractures. The petrous portion of the temporal bone is seen best in this view. It houses the otic capsule, internal audiotry canal, petrous carotid, and portions of the facial nerve and forms the petrous apex.

Figure 6.3 Axial view of the left temporal bone, with longitudinal fracture (red dotted line) extending through the petrous apex into the sphenoid.

145

www.entnet.org