Search Results (2)

Background and Objectives: After major upper-limb amputation, people face challenges due to losing tactile information and gripping function in their hands. While vision can confirm the success of an action, relying on it diverts attention from other sensations and tasks. This case report presents a 30-year-old man with traumatic, complete vision loss and transradial left forearm amputation. It emphasizes the importance of restoring tactile abilities when visual compensation is impossible. Materials and Methods: A prototype tactile feedback add-on system was developed, consisting of a sensor glove and upper arm cuff with related vibration actuators. Results: We found a 66% improvement in the Box and Blocks test and an overall functional score increase from 30% to 43% in the Southampton Hand Assessment Procedure with feedback. Qualitative improvements in bimanual activities, ergonomics, and reduced reliance on the unaffected hand were observed. Incorporating the tactile feedback system improved the precision of grasping and the utility of the myoelectric hand prosthesis, freeing the unaffected hand for other tasks. Conclusions: This case demonstrated improvements in prosthetic hand utility achieved by restoring peripheral sensitivity while excluding the possibility of visual compensation. Restoring tactile information from the hand and fingers could benefit individuals with impaired vision and somatosensation, improving acceptance, embodiment, social integration, and pain management. Full article

Focal vibration therapy seeks to restore the physiological function of tissues and the nervous system. Recommendations for vibration settings, e.g., that could improve residual limb health and prosthesis acceptance in people with amputation, are pending. To establish a physiological connection between focal vibration settings, clinical outcomes, and molecular and neuronal mechanisms, we combined the literature on focal vibration therapy, vibrotactile feedback, mechanosensitive Piezo ion channels, touch, proprioception, neuromodulation, and the recovery of blood vessels and nerves. In summary, intermittent focal vibration increases endothelial shear stress when applied superficially to blood vessels and tissues and triggers Piezo1 signaling, supporting the repair and formation of blood vessels and nerves. Conversely, stimulating Piezo1 in peripheral axon growth cones could reduce the growth of painful neuromas. Vibrotactile feedback also creates sensory inputs to the motor cortex, predominantly through Piezo2-related channels, and modulates sensory signals in the dorsal horn and ascending arousal system. Thus, sensory feedback supports physiological recovery from maladaptations and can alleviate phantom pain and promote body awareness and physical activity. We recommend focal vibration of phantom limb maps with frequencies from ~60–120 Hz and amplitudes up to 1 mm to positively affect motor control, locomotion, pain, nerves, and blood vessels while avoiding adverse effects. Full article