Delayed onset of Lhermitte's sign following head and/or neck injuries. Report of four cases.

The authors report four patients who suffered the delayed onset of Lhermitte's sign following head and/or neck trauma with no significant neurological deficits. The average onset from the time of the injury was 2 1/2 months. In all patients, there was a full range of movement of the cervical spine with no tenderness and no neurological deficits. Myelography was performed in three of the four patients and was normal. The duration of Lhermitte's sign ranged from 4 months to 1 year (mean 8 months). Complete recovery occurred in all cases. The pathogenesis, differential diagnosis, and management of patients with Lhermitte's sign are discussed.