Grooved pegboard test performance before and after cerebral-spinal fluid tap test in patients with normal pressure hydrocephalus

Abstract

Background Motor impairment in patients with normal pressure hydrocephalus (NPH) can extend beyond gait and include deficits in upper extremity functions and psychomotor speed. Evaluation of upper extremity function will be helpful for NPH patients who are unable to ambulate (e.g., wheelchair-bound patients) and may not be able to comply with the gait evaluation. Our study aimed to explore the use of the grooved pegboard test to assess responsiveness to the cerebrospinal fluid (CSF) tap test in patients with NPH. Methods Seventy-five possible NPH patients were enrolled from 2012 to 2018. All patients underwent detailed neuropsychological and walking assessments, CSF tap tests, and brain magnetic resonance imaging. The grooved pegboard test results before and after the CSF tap test were compared and correlated with the other clinical assessments. In diffusion tensor imaging analysis, the fractional anisotropy (FA) and mean diffusivity (MD) values of periventricular white matter were measured by the region of interest method and were correlated with pegboard test performance. Results The grooved pegboard test scores significantly improved after the CSF tap test and correlated with patient walking ability, cognitive function, and functional scores (P < 0.01). The improvement ratios in the complex visual motor speed index (i.e., the grooved pegboard test performance combined with the Symbol-Digit Modalities Test performance) were significantly different between the CSF tap test responder and nonresponder groups. The grooved pegboard test times were significantly correlated with the FA values in right periventricular lesions (P=0.017). Conclusions The performance on the grooved pegboard test was related to lower extremity motor ability and cognitive function. It can be used as an alternative evaluation tool for patients who are unable to ambulate and may not be able to comply with the gait evaluation.