SPINAL-CORD STIMULATION REVISITED

The proportion of patients with intractable pain successfully managed with spinal cord stimulation (SCS) remains disputed. We analyze 27 con secutive patients with intractable pain treated with SCS using identic al hardware (Itrel(R) II System; Medtronic Neurological, Inc., Minneap olis, MN, USA) by a single neurosurgeon(RS) 1992 through 1995. A rigid selection protocol was used: I. A satisfactory diagnosis of the patho logic process resulting in pain was made. 2. A corrective surgical pro cedure was judged not feasible by surgeons experienced in the particul ar pathology, e.g., vascular, peripheral nerve, spine. 3. Lack of sati sfactory response to noninterventional pain management modalities by a n interdisciplinary pain clinic. 4. Independent psychological evaluati on, including a structured interview was performed by a psychologist s pecialized in chronic pain management. In the last eight cases, a batt ery of self-report tests designed to assess psychosocial and behaviora l consequences of the chronic pain problem were administered as well. All cases were of nonmalignant pain, except for one patient. Thirteen cases were diagnosed with failed back surgery syndrome (FBSS), one old er patient with lumbosacral radiculopathy who refused decompression, o ne with cervical radiculopathy and Klippel-Feil syndrome, six with ref lex sympathetic dystrophy (RSD) two with peripheral vascular ischemic disease, one with post-thoracotomy pain syndrome, one with leg pain fo llowing resection of angiolipoma, one with traumatic superficial peron eal neuropathy, and one with Pancoast's tumor. Fifteen patients were f emale and twelve were male. All were Caucasian. Their ages ranged from 27 to 84 years (mean: 48). The average follow-up was 21 months (range : 48-6). All patients underwent a three day trial screening with Pisce s-Quad/Resume(R) epidural leads connected to a temporary external stim ulator. An Itrel(R) II System pulse-generator was internalized in each of the 24 patients who had a successful trial (three cervical and twe nty-one thoracic-lumbar). There was no morbidity. Pain reduction was s ustained in 22 out of the 24 patients who continue to use the stimulat or. The same number would choose to receive an electrical stimulator a gain. Normalization or improvement in Quantitative Sudomotor Axon Refl ex Test (Q-SART) and Thermography was documented in the patients with RSD. We conclude that a rigid selection protocol can maximize the prop ortion of patients with intractable pain who are successfully treated with SCS. Strict neurosurgical technique eliminates infection risk. Ha rdware selection minimizes incidence of malfunction.