Facial nerve palsy after head injury: Case incidence, causes, clinical profile and outcome.

BACKGROUND

To investigate the case incidence, causes, clinical profile, and outcome of facial nerve palsy complicating head trauma.

METHOD

A 10-year (1991-2000) retrospective study of head injured patients at the University Teaching Hospital, Ilorin, Nigeria. Age, gender, and neurologic findings were analyzed.

RESULTS

Of 794 patients, facial nerve palsy occurred in 40 (5.04%). Facial nerve was the most frequently injured cranial nerve, followed by vestibulo-cochlear (12 [1.5%]) and abducens (8 [1.0%]). Majority (70%) of the seventh nerve palsies were of the lower motor neurone type. The left nerve was more frequently affected (60%). Facial nerve palsy was more common in male patients and adults with a peak incidence at the 4th decade. Spontaneous functional recovery occurring within 6 to 24 months of injury was total in 12 (30%), partial in 5 (12.3%), and none in 3 (7.5%) subjects. Thirteen patients died giving a mortality rate of 32.5%. The patients were aged 5 to 85 years (mean, 34 years). Causes of head trauma were traffic injuries (82.5%), fall from height (7.5%), assault (5%), and gunshot (2.5%). Though patient mortality rate was higher among patients with facial nerve palsy (32.5%) than those without (23.04%), facial nerve palsy was not a strong predictor of fatality (p = 0.2950).

CONCLUSION

The case incidence of facial nerve palsy in head injured patients in our center is 5.04%. The lower motor neurone type predominates. It is commoner in men and on the left side with spontaneous recovery occurring in 30% of cases.