Peripheral nerve stimulation for pain relief in CRPS II and phantom-limb pain

Abstract

We performed 52 peripheral nerve stimulation procedures since 1991. In addition to 48 patients with CRPS II, 4 patients with phantom-limb pain were treated. Incomplete or complete lesion of the stimulated peripheral nerves was determined in all patients. Surgically treatment failed in all cases. All patients had been given extensive conservative pain therapy. The aim was to define a standardised method, which would be as objective as possible, to verify the success of treatment, by measuring the pain-related disability assessment, the subjective intensity of pain and the subjective perception of pain. Long-term follow-up was arranged in addition to determine social and occupational re-integration. The implantation of the stimulating electrode, proximal to the lesion, was performed after microsurgical neurolysis of the peripheral nerves. The patient carried out a stimulation trial after the operation. At the conclusion of the trial stimulation phase, a stimulator unit was permanently implanted in 47 cases, with a marked reduction in pain. Only in 5 cases, the success of the trial stimulation was unsatisfactory. After implanting the stimulator unit an average pain-related disability of 10% was achieved by the 47 patients fitted with a permanent implant. 43 patients have used the permanent stimulator implants with lasting, excellent to good success. The stimulator system was removed in only 4 cases, due to the need for stimulation having passed, or due to a lack of lasting success with stimulation. Neurostimulation of peripheral nerves should be considered as an established concept to treat surgically failed peripheral nerve lesions.