Male and Female over the age of 18 who have had a total knee replacement at least nine months ago. Continue with unilateral knee pain equal to or greater than 4 on a 1 to 10 scale. Subjects will receive a trial placement of spinal cord stimulator for 5 to 10 days. if trial is successful subjects will proceed to permanent placement of stimulator for the treatment of the knee pain. subjects will then be followed post implant to assess the effectiveness of the stimulator for the pain.