Italian multicentric study on pain treatment with epidural spinal cord stimulation.

A multicentric study on the treatment of nonmalignant chronic pain with epidural spinal cord stimulation (SCS) has been carried out in 32 Italian centers devoted to pain therapy. Neurosurgical and anesthesiology units participated in this retrospective study. 410 of the eligible patients were enrolled in the protocol: 48% were male, 52% female. All patients underwent a screening test period (average 21 days) and 74% underwent the definitive implant. The diagnosis was failed back surgery syndrome in 45%, reflex sympathetic dystrophy in 15%, phantom limb pain in 14%, postherpetic neuralgia in 8%, peripheral nerve injury in 5%, others 13%. 84% received noninvasive unsuccessful treatment (10 tensor acupuncture). All had previous pharmacological therapy which was not always discontinued when SCS took place. Pain assessment had been done with the visual analog scale and verbal scale both subjectively and by the physician and nurses. Neuropsychological profile with minimal mental test or MMPI was obtained in 68% of the patients. These results were favorable (i.e. excellent or good; more than 50% reduction of pain) in 87% of the patients at the 3-month follow-up, 75% at the 6-month follow-up, 69% at the 1-year follow-up, and 58% at the 2-year follow-up. Complication rate was: dislocation of the electrocatheter 4%, technical problems 3%, infections of the system 2%. The results will be discussed in correlation with the different etiologies of the nonmalignant chronic pain syndrome.