A head injury involving a transverse fracture of the temporal bone through the otic capsule is most likely to produce which type of hearing loss?

• A. No hearing loss
• B. A transient sensorineural hearing loss
• C. A conductive hearing loss
• D. A permanent sensorineural hearing loss

Answer: (D)

When a transverse fracture passes through the otic capsule, the inner ear structures of the cochlea and vestibular system are directly damaged. This injures the sensory cells and neural pathways responsible for hearing, so the resulting loss is sensorineural rather than conductive. Because cochlear hair cells do not regenerate in humans, this sensorineural loss tends to be permanent. In contrast, fractures that spare the otic capsule often cause conductive loss from disruption of the middle ear bones, but the otic capsule injury specifically points to inner-ear damage and a lasting SNHL. Additional signs such as vertigo or facial nerve involvement may also occur with this type of fracture due to broader temporal bone injury.