Bilateral Lower Cranial Nerve Palsy after Closed Head Injury: A Case Report and Review of Literature

Paralysis of the lower cranial nerves is uncommon after closed head injuries. Most cases reported are unilateral and associated with base of skull fractures, usually involving the occipital condyles. Bilateral lower cranial nerve palsy is even less common, with only a handful of cases reported in literature. A 17-year-old girl presented to us after she was involved in a side-on collision with a car while driving a scooter. She sustained traumatic brain injury requiring mechanical ventilation. Detailed neurological evaluation revealed bilateral paralysis of the IX(th), X(th), and XII(th) cranial nerves with no evidence of a fracture of the base of skull or brain stem injury. A traction type of injury to the nerves arising from a whiplash mechanism may have led to paralysis of the lower cranial nerves in our patient. An exhaustive review of literature revealed 11 reports of bilateral lower cranial nerve palsy associated with closed head injuries; there were only four cases without underlying fracture of the occipital condyles. Our patient made a complete recovery over a period of 4 months. A traction type of injury to the lower cranial nerves may occur due to a whiplash mechanism. This type of injury may be associated with a favorable outcome.