Cadaveric dissections based on observations of injuries to the temporal bone structures following head trauma.

One hundred temporal bones obtained from forensic autopsies were dissected to expose injured structures. Longitudinal fractures were present in 82%, transverse fractures in 11%, and mixed fractures in 7% of the cases. Facial canal injuries were present in almost half of the bones with longitudinal fractures (36/82), although cuts of the facial nerve stem were rarely encountered. Damages to the facial canal associated with longitudinal fractures were most frequently seen in the region of the geniculum. However, transverse fractures with facial canal involvement (7/11) most frequently occurred in the labyrinthine portion, causing a complete cut of the facial nerve. Injuries to the jugular bulb were also common (21/100) and associated with all types of temporal bone fractures. Observed damages to the auditory ossicles included disconnection of their joints or fractures of the malleus or stapes. Fractures of the incus were not observed. Injuries to the carotid canal were common (52/100), although an injury to the arterial wall was observed in only one specimen. The frequency and nature of damage in temporal bone fractures strictly reflect the type of fracture, especially in terms of facial nerve disorders: the most serious damage is observed with fractures that involve the otic capsule.