We studied the effects of spinal cord stimulation (SCS) on postherpetic neuralgia (PHN). Data of 28 patients were prospectively investigated over a median period of 29 (quartiles 9--39) mo. In addition, four patients with acute herpes zoster (HZ) pain were studied simultaneously. After intractable pain for more than 2 yr, long-term pain relief was achieved in 23 (82%) PHN patients (median, 70 yr) during SCS treatment confirmed by a median decrease from 9 to 1 on the visual analog scale (P < 0.001). In five cases with serious comorbidity, the initial pain alleviation could not be stabilized. Spontaneous improvement was always confirmed or excluded by SCS inactivation tests at quarterly intervals. Eight patients discontinued SCS permanently because of complete pain relief after stimulation periods of 3--66 mo, whereas 2 reestablished SCS because of recrudescence after 2 and 6 mo. Considerable impairments in everyday life, objectified by the pain disability index, were also significantly improved (P < 0.001). In 4 patients with acute HZ pain, SCS was promptly effective and after periods of 2.5 (quartiles 2--3) months the pain had subsided. SCS seems to offer a therapeutic option for pharmacological nonresponders.
Implications: In many patients with postherpetic neuralgia and acute herpes zoster pain is not satisfactorily alleviated with pharmacological approaches. We report on 23 of 28 patients with postherpetic neuralgia and 4 of 4 with acute herpes zoster whose chronic pain was improved by electrical spinal cord stimulation.