The best candidates for SCS implantation have severe chronic pain in their legs or arms. Patients with primarily leg or arm pain and mild back and neck pain can also benefit. In general, the wider the area of pain, the more difficult it is for SCS to be effective. Most patients who have tried more conservative therapies, but who have not experienced sufficient pain relief, are considered candidates for SCS therapy. The patient's doctor often feels that surgery would not be beneficial.