A Wearable Multi-Site System for NMES-Based Hand Function Restoration

Abstract

Reaching and grasping impairments significantly affect the quality of life for people who have experienced a stroke or spinal cord injury. The long-term well-being of patients varies greatly according to the restorable residual capabilities. Electrical stimulation could be a promising solution to restore motor functions in these conditions, but its use is not clinically widespread. Here, we introduce the HandNMES, an electrode array (EA) for neuromuscular electrical stimulation (NMES) aimed at grasp training and assistance. The device was designed to deliver electrical stimulation to extrinsic and intrinsic hand muscles. Six independent EAs, positioned on the user forearm and hand, deliver NMES pulses originating from an external stimulator equipped with demultiplexers for interfacing with a large number of electrodes. The garment was designed to be adaptable to user needs and anthropometric characteristics; size, shape, and contact materials can be customized, and stimulation characteristics such as intensity of stimulation and virtual electrode location, and size can be adjusted. We performed extensive tests with nine healthy subjects showing the efficacy of the HandNMES in terms of stimulation performance and personalization. Because encouraging results were achieved, in the coming months, the HandNMES device will be tested in pilot clinical trials.

Development of a Hand Neuroprosthesis for Grasp Rehabilitation After Stroke: State of Art and Perspectives

“…The hand neuroprosthesis described in this paper is able to recover and support person's ability to perform exercises based on ADL in subjects with upper limb impairment due to stroke at the sub-acute and at the early chronic stage. Pilot tests with with previous embodiments of the device [8] proved to be insightful in defining anthropometric requirements and practicality requirements usually not needed in healthy populations. The current set of wearables allows to fit the target population, and to functionally constrain the movement for the exercises as needed.…”

A Hybrid Robotic System for Arm Training of Stroke Survivors: Concept and First Evaluation

“…Finally, the RETRAINER-ARM system only supports arm rehabilitation, while many stroke survivors also need to recover wrist and hand functions. To overcome this limitation, the RETRAINER-HAND system has been developed within the context of the same European project [35]. The two systems have been designed in a way that they could be easily integrated, making therefore available a complete platform for the recovery of arm and hand functions after stroke.…”

“…This work proposes a hybrid robotic system, called RETRAINER-ARM system, for arm stroke rehabilitation [34]. This system was designed within the European project RETRAINER, which in parallel was focused on the development of a wearable multi-site FES system for hand function restoration [35].…”

Wireless IMU- and EMG-Sensors for Controlled Functional Electrical Stimulation

“…Therefore, a hybrid arm rehabilitation system, called RETRAINER S1, has been developed within the European project RETRAINER that combines both technologies [1]. Additionally, a hand rehabilitation system, called RETAINER S2 has been built, that can be used separately from S1 [3].…”

“…The S2 hand rehabilitation system consists of an array electrode in combination with a wrist/hand orthosis with the corresponding author: wiesener@control.tu-berlin.de) E. Ambrosini is with the Department of Electronics, Information and Bioengineering at Politecnico di Milano, Italy. integrated wired IMU sensors [3].…”