Gait disturbance in patients with low pressure hydrocephalus.

Using criteria of the classification recently described by Nutt et al., we examined gait disorder in five patients with normal pressure hydrocephalus (NPH). Their cerebrospinal fluid (CSF) pressures were in the normal range, and trials of CSF removal produced temporary improvement of symptoms. Surgical procedures to relieve hydrocephalus improved gait disorders in all patients. No patient showed spasticity, sensory ataxia, cerebellar ataxia, extrapyramidal signs, or limb apraxia. All walked slowly with a wide base and a short stride. The arm swing normally associated with walking was preserved. In standing, patients were unsteady and fell easily when pushed. Four patients showed hesitation in initiating walking and in turning. These clinical features fit Nutt's criteria for frontal gait disorder and frontal disequilibrium. Unlike findings in Parkinson's disease, where similar gait disorders may occur, other extrapyramidal signs, Myerson's sign, and upper limb dysfunction were absent in NPH, and arm swing while walking was preserved. We suspect that ventricular dilatation disturbs neuronal connections between the supplementary motor area and the globus pallidus in NPH patients.