Fractures of the petrous pyramid; report of a case with histological observations eight years after injury.

Abstract

FRACTURES of the petrous pyramid are commonly classified as (1) longitudinal and (2) transverse. The longitudinal fractures have been encountered far more frequently than the transverse. This is well shown in the comprehensive clinical study by Grove. 1 He analyzed 211 cases of fracture of the skull including 162 cases of temporal bone fractures, of which 146 were longitudinal and 16 transverse. Longitudinal fractures are characterized by a break through the tegmen tympani or antri and by injury to the tympanic membrane and often to the external auditory canal. There is usually free bleeding from the ear. The bony capsule of the labyrinth is seldom involved. The transverse fractures, on the other hand, are characterized chiefly by injuries to the inner ear and bony capsule. Hemorrhage into the inner ear and tearing of the seventh and eighth nerves are frequent accompaniments. A third type to be considered, and one which