Laminectomy versus percutaneous electrode placement for spinal cord stimulation

OBJECTIVE: The purpose of this study was to compare the long-term effective ness of spinal cord stimulation using laminectomy-style electrodes versus t hat using percutaneously implanted electrodes. METHODS: Forty-one patients underwent an initial trial period of spinal cor d stimulation with temporary electrodes at Duke Medical Center between Dece mber 1992 and January 1998. A permanent system was implanted ii trial stimu lation reduced the patient's pain by move than 50%. Median long-term follow -up after permanent electrode placement was 34 months (range, 6-66 mo). Sev erity of pain was determined postoperatively by a disinterested third party using a visual analog scale and a modified outcome scale. RESULTS: Twenty-seven (66%) of the 41 patients participating in the trial h ad permanent electrodes placed. Visual analog scores decreased an average o f 4.6 among patients in whom electrodes were placed via laminectomy in the thoracic region (two-tailed t test, P < 0.0001). Patients who underwent per cutaneous placement of thoracic electrodes had an average decrease of 3.1 i n their visual analog scores (two-tailed t test, P < 0.001). Electrodes pla ced through laminectomy furnished significantly greater long-term pain reli ef than did those placed percutaneously, as measured by a four-tier outcome grading scale (P = 0.02). CONCLUSION: Spinal cord stimulation is an effective treatment for chronic p ain in the lower back and lower extremities that is refractory to conservat ive therapy. Electrodes placed via laminectomy in the thoracic region appea r to be associated with significantly better long-term effectiveness than a re electrodes placed percutaneously.