Alternative Approach To Needle Placement In Spinal Cord Stimulator Trial/Implantation

Abstract

Neuromodulation with spinal cord stimulation is a proven, cost effective treatment for the management of chronic radicular low back pain from failed low back surgery syndrome and other neuropathic pain conditions. The traditionally instructed method for percutaneous spinal cord stimulator lead placement promotes the use of a “loss of resistance” technique under anteroposterior fluoroscopic guidance to assure midline lead placement and proper entry into the epidural space. Loss of resistance is a reliable method to locate the epidural space in most clinical situations. However, in certain circumstances such as a congenital underdeveloped ligamentum flavum or defects of the ligamentum flavum, sometimes occurring after lumbar spine surgery, it might become difficult to use a loss of resistance technique to locate the epidural space. In this case, the level of resistance might not be clear. Further, a false loss of resistance might occur between changes in fascial planes that might lead to the uncertainty of needle depth. This paper introduces an alternative method for needle placement for spinal cord stimulator (SCS) trials and implantation without using the traditional loss of resistance technique. The technique allows for precise visual monitoring of the Tuohy needle tip under fluoroscopy to gauge needle depth as it enters into the tissue and the epidural space based on anatomic structural landmarks. This method allows for multiple lead placement or single lead insertion multiple times in the same interlaminar space. This is an alternative approach to the loss of resistance technique based on the fluoroscopic landmarks. Theoretically, this should be a safer approach for accessing the epidural space; however, further studies are needed to evaluate its safety. Key words: spinal cord stimulator, loss of resistance, epidural access, lumbar radicular symptoms of lower limbs, neuromodulation, posterior column stimulator