Background: The clinical spectrum of idiopathic normal pressure hydrocephalus (iNPH) comprises the triad of gait disturbance, cognitive impairment, and urinary incontinence. However, motor abnormalities involving the upper extremities in iNPH patients have few quantitative studies.
Objective: The present study was designed to quantitatively assess bimanual tapping tasks in iNPH patients and to compare with the control groups.
Methods: The subjects were divided into three groups: iNPH patients, older healthy group, and younger healthy group. The tasks were three synchronization finger-to-thumb tapping tasks with the auditory stimuli specified at 1 Hz by metronome: unilateral, bimanual simultaneous, and bimanual alternate. Two-way ANOVA was used to compare the outcomes of the three errors (absolute error: AE, variable error: VE, and constant error: CE) for tapping cycles.
Results: In the iNPH group, the absolute and variable errors increased in bimanual alternate tapping task with statistical significance (AE: p < 0.05 and VE: p < 0.05). There were no significant differences in errors between the older and young healthy groups (AE: p = 0.62, CE: p = 1.00 and VE: p = 0.31).
Conclusions: We could quantitatively evaluate the bimanual coordination on iNPH patients using the bimanual alternate tapping task, potentially useful for evaluating patients unable to walk.
Keywords: Idiopathic normal pressure hydrocephalus; bimanual coordination; finger-to-thumb tapping; occupational therapy; upper extremity.