Intermittent gait disturbance in idiopathic normal pressure hydrocephalus

ObjectivesWe identified intermittent gait disturbance (IGD) observed in the mild stage of idiopathic normal pressure hydrocephalus (iNPH). The first purpose of this study was to clarify the temporal gait profile of IGD during long-distance gait. The second purpose was to confirm the difference in treatment effect after cerebrospinal fluid (CSF) shunting in patients with and without IGD. Materials and MethodsFourteen consecutive iNPH patients with mild gait disturbance with a timed up-and-go (TUG) of <20seconds were prospectively enrolled in the study. All patients were asked Do you experience gait difficulty after over five minutes of walking? Seven yes patients formed the IGD group, and seven no patients formed the persistent gait disturbance (PGD) group. One day before and 7days after CSF shunting, gait function was evaluated by the 6-minute walk test (6MWT) and TUG. ResultsPreoperatively, all patients in the IGD group demonstrated features of IGD during the 6MWT, characterized by a progressive pattern of decreased gait speed and step length with increased cadence and absence of leg pain. Post-operatively, these features of IGD improved in all patients. In the PGD group, preoperative walking did not significantly worsen during the 6MWT and did not significantly change 7days after treatment. Improvement of gait symptoms 1week after CSF shunting could be detected with 6MWT instead of TUG. ConclusionsIntermittent gait disturbance is not a rare symptom in mild stage of iNPH and may serve as an important clinical diagnostic marker for identifying mild iNPH patients.