Change in Impedance with Change in Posture during Spinal Cord Stimulator Placement

In this article we discuss the effect of posture on impedance during the placement of a spinal cord stimulator. Although, according to several studies, there appears not to be a specific and consistent change in impedance with change in posture, we noticed on multiple occasions that if the impedance remains very high during spinal cord stimulator (SCS) lead placement, asking the patient to sit up from the prone position may drop the impedance down. This could be explained by having air around the lead, from using loss of resistance to air technique in finding the epidural space, which moves up when sitting the patient up, or having the lead immersed in epidural fat. Sitting the patient up from the prone position should be tried if the impedance remains very high before aborting the procedure and taking the lead out.