Serial Assessment of Gait Changes After Interventions Using Smart Insole in a Patient With iNPH: A Proof-of-Concept Case Report

Improvement in gait after a cerebrospinal fluid (CSF) tap test is a key indicator for shunt surgery in idiopathic normal pressure hydrocephalus (iNPH) patients. However, quantitative analysis of gait requires sophisticated equipment and specialists that limit practical use. Development of Bluetooth-connected sensors offers affordable way to assess gait. We present a case of iNPH patient in whom gait changes were serially assessed using a smart insole before and after intervention, which helped in clinical decision making. A 68-year-old female who showed the triad of iNPH symptoms (gait disturbance, cognitive decline, and urinary frequency) were evaluated. Before and after the CSF tap test, gait was analyzed and compared using the smart insole with four pressure sensors and accelerometer, along with conventional spatiotemporal parameters. While no significant changes were observed between pre- and post-tap test in conventional parameters of gait, several changes were found in the data collected from the smart insole, including improved heel strike, step regularity and symmetry. Advanced surgical intervention was performed based on subjective and objective improvement in gait. The improved gait was maintained at 3 and 6 months after surgery. Our case showed that easy-to-use smart insoles could assist clinical decisions by providing additional information.