A Neuroprosthesis for Seated Posture and Balance

VA Office of Research and Development10 enrolled

Overview

The purpose of this study is to evaluate a surgically implanted functional electrical stimulation (FES) system to facilitate stability of the trunk and hips. FES involves applying small electric currents to the nerves, which cause the muscles to contract. This study evaluates how stabilizing and stiffening the trunk with FES can change the way spinal cord injured volunteers sit, breathe, reach, push a wheelchair, or roll in bed.

In a single surgical procedure electrodes will be inserted into muscles of the trunk and hip musculature. The electrode leads are connected to a stimulator/telemeter located in the abdomen. After a typical post-operative period of two to five days, neuroprosthesis recipients will be discharged to home for two to six weeks of restricted activity to promote healing of all surgical incisions. After a period of exercise and training, functional use of the neuroprosthesis will begin. Laboratory assessments of strength, balance, and functional abilities with and without the system, as well as the technical performance of the implanted components will be evaluated.

Study Type

INTERVENTIONAL

Allocation

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Spinal Cord Injury Paralysis

Eligibility

Sex: ALLMin age: 21 Years

Medical Language ↔ Plain English

Inclusion Criteria: * C4-T12 * ASIA Scale A through C * Time post injury greater than 6 months * Innervated and excitable trunk and pelvis musculature * Absence of acute or chronic psychological problems or chemical dependency * Range of motion within normal limits * Controlled spasticity and absence of hip flexion and adduction spasm * Height and weight within normal limits * No history of balance problems or spontaneous falls * No history of spontaneous fracture or evidence low bone density * No acute orthopaedic problems * No acute medical complications * Adequate social support and stability * Able to speak and read English Exclusion Criteria: * Pregnancy * Non-English speaking

Outcomes

Primary Outcomes

Effect of Trunk stimulation on control seated posture, respiration, seated interface pressures, reach ability, seated stability & personal mobility.

Experiments involving the effects of trunk stimulation on postural alignment; trunk stability and posture on respiration, postural variation on seated interface pressures; effects of trunk stimulation on reaching ability; effects of trunk stimulation on seated stability, and personal mobility.

Time frame: up to 36 months

Secondary Outcomes

Design a simple position controller

The position controller will be developed to keep the trunk posture at a neutral seated position while allowing movement to lean forward, backward, or side-to-side. Testing will be carried out with an automated pull system applied to the trunk which pulls the body in various ways (side-to-side, forward, backward)

Time frame: Up to 36 months