Pneumatic Plantar Stimulation Device Replicating Manual Therapy Improves Lateral Stability in Standing Posture

Strokes are a widespread condition characterized by motor paralysis and sensory impairment, and they significantly hinder daily activities. Hence, rehabilitation aimed at improving motor function is crucial for post-stroke patients. Manual therapy, which involves the manual stimulation of the limbs to provide sensory input and enhance motor function, is commonly employed for rehabilitation. However, the limited duration of inpatient rehabilitation highlights the need for devices that can provide similar rehabilitation interventions at home. Here we elucidate the skills employed by physical therapists during intervention through interviews and measurements of the force applied to the plantar surface of the foot. Subsequently, we develop a device capable of replicating these intervention skills. The investigation of physical-therapist skills revealed the importance of stimulating the muscles involved in forming the longitudinal and transverse arches and the flexor muscles of the toes during manual therapy. The required force for stimulation was also noted. Using our device, which utilized pneumatic actuation to replicate therapist skills, intervention on the plantar surface of the feet of healthy adults demonstrated improved stability in their standing posture, particularly in the lateral direction. These devices can enhance the sensory-motor connection from the plantar surface, thereby improving motor abilities, such as preventing falls.