Electrical stimulation of motor nerves: results of an animal experiment

In an animal experiment, the effect of long-term electrical stimulation by a totally implanted stimulation system were studied. The threshold value of the femoral nerve of the cat was registered before, during and after the stimulation period. Contraction strength was measured, and after the experiment the histology of the nerve and muscle was examined and compared with the non-stimulated samples. As a result, there was a slight increase in the threshold value after six months, with initially an increase of contraction strength, but after six months there was a decrease to the values measured at the start of the stimulation period. No signs of nerve degeneration were seen except in one nerve. Moreover, no change could be found in the number and distribution pattern of muscle fibres. Although one should be careful in drawing conclusions from an animal experiment when attempting to apply the results to human beings, this method of electrical stimulation might be a reliable therapy in regaining the function of paretic muscles in patients who have a central paresis.