OTAKA YOHEI

OBJECTIVES: To investigate the feasibility of robot-assisted hand movement training using a novel end-effector robot in individuals after stroke. METHODS: Eleven individuals with subacute stroke with hand motor impairment underwent robot-assisted repetitive finger flexion/extension for 20 min daily and repeated this training on 7 non-consecutive days. The robot was designed to allow the flexion and extension of the metacarpophalangeal and proximal interphalangeal joints of the index to the little fingers, and to provide assistive torque if the movement did not reach the target angle within a limited time. We assessed the co-contraction index (CCI) of the flexor digitorum superficialis and extensor digitorum muscles and assessed the active range of motion (AROM) of the index finger before and after training each day (intra-day effect). We performed clinical assessments of motor function and spasticity and evaluated the CCI and AROM before and immediately after the 7-day training (inter-day effect). RESULTS: Ten participants completed the 7-day training. For the intra-day effect, the CCI was significantly decreased immediately after training, particularly during active finger flexion, and the AROM tended to improve from the middle of the training days. For the inter-day effect, there were no significant changes in the Stroke Impairment Assessment Set for Finger Function, modified Ashworth scale, CCI, or AROM after the 7-day training. CONCLUSIONS: Repetitive finger movement training with the assistance of the novel robot improves muscle activation patterns, reducing co-activation between the agonist and antagonist muscles immediately after training.

BACKGROUND: The use of diapers among older adults is increasing in aging societies. However, the optimal method of wearing them remains unknown. We aimed to explore procedural variations in leg-through motion during diaper wearing in older adults. METHODS: A multicenter cross-sectional study was conducted in 19 facilities in Japan. Individuals aged 65-99 years in nursing homes/adult daycare facilities and able to maintain a sitting posture in a chair were recruited via convenience sampling between March 2024 and January 2025. Leg-through motion during diaper wearing was recorded with the participants seated in a chair. The motion patterns were visually classified according to predetermined criteria. The classification of the observed motion patterns was subjected to a simple descriptive analysis. The inter-rater agreement of the classifications between the two assessors was determined using Cohen's kappa coefficient. RESULTS: Among 149 older adults (mean [standard deviation] age: 87.0 [7.2] years), the motions "keep the foot off the floor and use both hands" and "keep feet on the floor and use both hands" collectively accounted for 65.7% of the initial leg motions. For the subsequent leg, three motions-"keep the foot off the floor and use contralateral hand," "keep the foot off the floor and use ipsilateral hand," and "keep the foot off the floor and use both hands"-accounted for a total of 59.1%. Furthermore, the leg-through motion patterns varied according to the participants' usual means of mobility. The inter-rater agreement was good for the initial leg (kappa = 0.72) and subsequent leg (0.80). CONCLUSIONS: We classified the motion patterns of older adults during diaper wearing. Our results provide fundamental insights into appropriate care and rehabilitation interventions. Furthermore, these findings inform further hypothesis-driven research on diaper-wearing kinematics and support the development of effective strategies to enhance independence diaper use in older adults.