Generally, patients with radicular pain to the lower extremities respond better to spinal cord stimulation than patients with isolated axial low back pain. However, a few studies have shown that axial low back pain in combination with bilateral leg pain, also respond well to spinal cord stimulation. Both four (e.g. quadripolar Quad lead) and eight (e.g. octapolar Octad® lead) electrodes were shown to be effective in treatment of low back and lower extremity pain, with no apparent advantage of one system over the other. In the recent PROCESS study publication, the reduction of SCS on low-back pain was not-statistically significant when compared to baseline. Even though it seems that eight electrodes may have the potential advantage in case of lead migration or disease progress, no clinical data have been published on the effectiveness of SCS using the octopolar epidural lead. The Octad study is a prospective, multi-center, open-label, non-randomized, interventional study designed to assess the effectiveness and technical performance of SCS with the Octad® lead for treatment of chronic pain. This study is not set up as a comparison study between the Octad lead and other SCS leads, such as the Quad lead, because the Octad lead is used in most eligible FBSS patients as the standard of care lead.