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

Neuromodulation with spinal cord stimulation is a proven, cost effective treatmentfor the management of chronic radicular low back pain from failed low back surgerysyndrome and other neuropathic pain conditions. The traditionally instructed methodfor percutaneous spinal cord stimulator lead placement promotes the use of a “lossof resistance” technique under anteroposterior fluoroscopic guidance to assuremidline lead placement and proper entry into the epidural space. Loss of resistanceis a reliable method to locate the epidural space in most clinical situations. However,in certain circumstances such as a congenital underdeveloped ligamentum flavumor defects of the ligamentum flavum, sometimes occurring after lumbar spinesurgery, it might become difficult to use a loss of resistance technique to locate theepidural space. In this case, the level of resistance might not be clear. Further, a falseloss of resistance might occur between changes in fascial planes that might lead tothe uncertainty of needle depth. This paper introduces an alternative method forneedle placement for spinal cord stimulator (SCS) trials and implantation withoutusing the traditional loss of resistance technique. The technique allows for precisevisual monitoring of the Tuohy needle tip under fluoroscopy to gauge needle depthas it enters into the tissue and the epidural space based on anatomic structurallandmarks. This method allows for multiple lead placement or single lead insertionmultiple times in the same interlaminar space. This is an alternative approach tothe loss of resistance technique based on the fluoroscopic landmarks. Theoretically,this should be a safer approach for accessing the epidural space; however, furtherstudies are needed to evaluate its safety.Key words: spinal cord stimulator, loss of resistance, epidural access, lumbarradicular symptoms of lower limbs, neuromodulation, posterior column stimulator