A Newly Developed Wearable Device for Continuous Measurement of Gait- Induced Accelerations in Daily Activities

For assessment of gait disorders, speed and stride are measured during 10m-walking test. However, changes in these two parameters are nonspecific since they are observed in various gait disorders. In addition, the10-m walking is short and reflects only one aspect of daily living and the results could be affected by emotional stress. To examine the step cycles and forces for step-in and kick off, which are directly controlled by a complex neural circuitry, during daily walking and over a long period of time, we developed a new wearing device, the portable gait rhythmogram (PGR), which monitors gait-induced accelerations for up to 70 hours. Quantitative analysis of the gait acceleration cycle and amplitude has allowed characterization of the bradykinematic features of gait disorders in patients with Parkinson’s disease: 1) A decrease in amplitude of gait acceleration in the early stages of the disease, which is compensated by fast stepping. 2) Subjective motor fluctuation did not necessarily coincide with changes in gait parameters. The results suggest that the rhythms-force correlation is set by the basal ganglia, but can be modified by the cerebral cortex. Analysis of voluntary gait in daily life could enhance our understanding of the pathomechanisms of gait disorders.