Fractures of the temporal bone--chain incongruencies.

PURPOSE: The sequela of a temporal bone fracture include hearing loss, vestibular dysfunction, and facial nerve injury. A large series of patients with temporal bone fractures are reviewed to correlate mechanism of injury, fracture location, and outcome.

PATIENTS AND METHODS: A retrospective analysis of patients evaluated between 1978 and 1987 for temporal bone fractures at two Swedish clinics was undertaken. Assessment of auditory, vestibular, and facial nerve function is reported. Follow up varied from 3 months to 12 years.

RESULTS: A total of 72 temporal bone fractures were encountered. Eleven patients had chain incongruencies, nine of whom were operated on with resultant good hearing. Transverse fractures were associated with severe sensorineural hearing loss while longitudinal fractures frequently were accompanied by ossicular disruption and persistent conductive hearing loss. Patients with vertigo or dizziness frequently had a good prognosis. Facial nerve injury occurred in 14 patients, eight of whom recovered.

CONCLUSIONS: Hearing loss following temporal bone fracture reflects the site and mechanism of injury. Transient conductive hearing loss may be due to blood in the middle ear, perforation of the tympanic membrane, or injury to the ossicular chain. Conductive loss persisting 6 to 7 weeks after trauma and exceeding 30 dB is an indication for surgical exploration.