Application of an implantable stimulator in the rehabilitation of paraplegic patients.

The surgical problems of implantable systems for functional electrical stimulation in the rehabilitation of plegic patients have been discussed. The "Ljubljana implant" was developed through experiments on animals and later with two volunteers. It has a typical electrode configuration, acceptable miniaturization and reduces the amount of surgery necessary. This system was tested in 14 patients, primarily as a part of an implantable peroneal brace. For five years the system has been reliable and safe. It may be possible to apply this implant as part of a multi-channel control system.

Treatment of drop foot using an implantable peroneal underknee stimulator.

An implantable peroneal stimulator has been developed to improve the rehabilitation of the drop foot patients who cannot use or refuse the use of conventionally applied peroneal braces. The small size promotes convenient attachment on the stimulation site after a minor surgical intervention. During the past two years twenty implants have been applied. The influence of different stimulation parameters upon the correction of anomalies during walking has been studied using clinical and computer-supported assessment. Possible noxious effects on the peroneal nerve have been studied by measuring nerve conduction velocity. The stimulator is well accepted by patients. Clinical observations show a significant correction of equinovarus and improved gait.

Gait evaluation in hemiparetic patients using subcutaneous peroneal electrical stimulation.

In hemiparetic patients with an implantable peroneal stimulator for correction of drop foot the gait pattern was studied over several years. The gait parameters and M-waves of subcutaneously stimulated muscles were compared with the results obtained before implantation and their variation was observed over time. Of a group of 35 patients with previously implanted electrodes 19 were evaluated. Significant improvements of gait were found although in some cases an excessive eversion of the foot was observed. Nine of these patients had reimplantation because of displacement of the stimulation electrodes after an average time of 3.5 years of proper functioning of the implant. After the reimplantations, similar gait patterns and muscular responses to stimulation were observed as after the initial implantation.