Original technique for noninvasive electric stimulation designed for the hoffmann® fixator

The standard Hoffmann fixator is ideal for electrical stimulation, using the pins as electrodes and the frame for fixation of the fracture and the stimulator. The main problem in this method of stimulation is the corrosion of the pins, which are made of stainless steel. Through 12 years of clinical research on human fractures, an electronic stimulator has been developed that eliminates the pin corrosion problem. The stimulator delivers an asymmetrical pulsating voltage with voltage- and current limitation, automatic pole reversing, patient control, and a continuous working time of six to nine months.Animal experiments have shown increased growth of blood vessels in osteotomies and activation of periosteal callus, using this means of stimulation. Experiments in humans have revealed 30% faster healing in fresh lower leg fractures, increasing difference of skin temperature between stimulated and nonstimulated bones, and increased uptake of labeled technetium of the whole bone when stimulated. Encouraging clinical results have been obtained in treatment of slow unions, pseudarthroses, and failed arthrodesis.