COMPUTER-CONTROLLED PORTABLE STIMULATOR FOR PARAPLEGIC PATIENTS

A six-channel lightweight, portable and computer-controlled stimulator for the functional activation of paraplegic patients is described. To enable programming of the various functions, the stimulator was desig ned to work in a remote-control mode hosted by an IBM PC or compatible computer, in addition to its normally used local mode. The stimulus p arameters, including current intensity, stimulus frequency and pulse w idth, are individually adjustable and programmable for each channel. T he power source is 12 V 500 m Ah-1, from 10 rechargeable nickel cadmiu m batteries, with a run time of 1. 5 h for a load of 200 mA in four ch annels. Various training programmes for the activation of paraplegics in the sitting, standing and walking positions are described. The fina l design of the stimulator is based on experience gained from 25 patie nts, treated and evaluated during the course of development. Ongoing w ork including clinical, biomechanical and physiological studies is car ried out to evaluate performance of the activated patients and to opti mize stimulation.