The bionic glove: an electrical stimulator garment that provides controlled grasp and hand opening in quadriplegia.

OBJECTIVE: This report describes the operation of the Bionic Glove, a new functional electrical stimulation (FES) device designed to improve the function of the paralyzed hand after spinal cord injury (SCI) or stroke. DESIGN: Signals from a sensor in the glove detecting voluntary wrist movement are used to control FES of muscles either to produce hand-grasp or to open the hand. When the glove is donned, conductive areas on its inside surface automatically make contact with self-adhesive electrodes on the skin. SETTING AND PATIENTS: This report concerns nine people with SCI who have used the device in their daily lives for up to a year or more. Measurements were made at clinics in Edmonton, Miami, and Chicago as part of a multicenter clinical trial. OUTCOME MEASURES AND RESULTS: The mean peak force of tenodesis grasp in the nine subjects increased from 2.6N (passive) to 11.3N (glove active). Active force was significantly greater than passive grasp force even when muscles were fatigued after repetitive grasp-release cycles. Most manual tasks improved significantly with the use of the glove, as judged by the number of tasks completed in a minute or the subjects' qualitative ratings of task difficulty. CONCLUSION: The Bionic Glove can provide significant improvement of hand function in people with C6-C7 SCI.

Instrumentation for ENG and EMG recordings in FES systems.

An electronic circuit for analog processing of neural (electroneurogram or ENG) and muscular (electromyogram or EMG) signals in functional electrical stimulation (FES) systems is described in this paper. The basic circuit consists of a low-noise gated preamplifier, band-pass filter, amplifier, and a blanking circuit to minimize stimulation artifacts during electrical stimulation. This device was tested in chronic recordings using a triphasic cuff electrode for nerves and epimysial electrodes for muscles in the hind limbs of cats. The device was used for nerve recordings in the presence of electrical stimulation of muscles in the same leg. The recordings showed rejection of stimulation and muscle (M-wave) artifacts, while retaining the information of interest.