Effect of spinal cord stimulation for chronic complex regional pain syndrome Type I: five-year final follow-up of patients in a randomized controlled trial

Abstract

Chronic complex regional pain syndrome-Type I (CRPS-I) is a painful, disabling disorder for which no treatment with proven effect is available. In the present randomized controlled trial, the authors assessed the effectiveness of spinal cord stimulation (SCS) in reducing pain due to CRPS-I at the 5-year follow-up. The authors performed a randomized trial in a 2:1 ratio in which 36 patients with CRPS-I were allocated to receive SCS and physical therapy (PT) and 18 patients to receive PT alone. Twenty-four patients who received SCS+PT also underwent placement of a permanent spinal cord stimulator after successful test stimulation; the remaining 12 patients did not receive a permanent stimulator. The authors assessed pain intensity, global perceived effect, treatment satisfaction, and health-related quality of life. Patients were examined before randomization, before implantation, and every year until 5 years thereafter. Ten patients were excluded from the final analysis. At 5 years posttreatment, SCS+PT produced results similar to those following PT for pain relief and all other measured variables. In a subgroup analysis, the results with regard to global perceived effect (p=0.02) and pain relief (p=0.06) in 20 patients with an implant exceeded those in 13 patients who received PT. Despite the diminishing effectiveness of SCS over time, 95% of patients with an implant would repeat the treatment for the same result.