Effects of Movement and Postural Positions in Spinal Cord Stimulation in the New Rechargeable Systems

Abstract

Background: Despite recent developments in implantable neurostimulation devices, the adjustment of stimulation levels to the patient’s postural changes has remained a problem so far. Objective: This study was conducted with the newest rechargeable devices, in order to compare its results with the ones published from conventional systems. Study Design: It is a prospective study. Setting: In 46 patients implanted with rechargeable constant current stimulation systems we measured impedance, stimulation thresholds, therapeutic range, as well patients’ satisfaction and sensation in 7 different body postures. Results: Data analysis was performed in 46 patients, whose most frequent pathologies were failed back surgery syndrome (FBSS) and complex regional pain syndrome (CRPS). The lowest amplitude needed to reach the different thresholds was always scored in the supine decubitus position, with no significant changes in the therapeutic range and impedance. For all stimulation thresholds, there is always a difference between the supine position and all other postures. No statistically significant differences with regard to patients’ satisfaction and sensation were found for the different postures. Limitations: Sample sample size. Conclusion: The findings of the present work are similar to those described in previous publications that showed the relationship between postural changes and several stimulation thresholds and pulse energy. The posture which requires lower energy — and whose corresponding therapeutic range (TR) is narrower — is supine decubitus. Key words: Spinal cord stimulation, change posture, rechargeable systems, sensor generation, threshold perception, threshold discomfort