Sub-Sensory Intraspinal Neurostimulation Therapy

Inclusion Criteria: * Primary pain complaint of persistent or recurrent low back and/or leg pain, with or without leg pain, for at least 180 days prior to Baseline. * Received a Boston Scientific SCS System with active contacts located between superior endplate of T7 and the inferior endplate of T10 with a minimum of three active contacts within this anatomical area. * No back surgery within 180 days prior to Baseline. * Has had stimulator "on" (activated or operational) for at least 36 hours prior to Baseline evaluation. * Average low back and/or leg pain intensity, during the position/activity which routinely causes worst pain, of 5 or greater on a 0-10 numerical rating scale without neurostimulation. * If taking prescription opioids for primary chronic pain complaint (low back and/or leg pain), must have been on a stable prescription (same drug(s) and dose(s)) for 30 days prior to Baseline * Consumed an average total daily morphine equivalent of ≤300 mg during the 30 days prior to Baseline * Willing and able to comply with all protocol-required procedures and assessments/evaluations (e.g. willing to comply with opioid prescription lock throughout the study, changes to the stimulation parameters, complete twice-daily diary) * 22 years of age or older when written informed consent is obtained * Able to independently read and complete all questionnaires and assessments provided in English * Subject signed a valid, IRB-approved informed consent form (ICF) provided in English Exclusion Criteria: * Any pain-related diagnosis or medical/psychological condition that, in the clinician's best judgment, might confound reporting of study outcomes (e.g. pelvic pain, chronic migraine, schizophrenia) * Current uncontrolled diabetes mellitus * Significant cognitive impairment at Baseline that, in the opinion of the Investigator, would reasonably be expected to impair the study candidate's ability to assess pain intensity and/or complete a pain diary * Participated in any investigational study within 30 days prior to the Screening Visit or is currently participating in another clinical trial that may influence the data that will be collected for this study * A female who is breastfeeding or of child-bearing potential with a positive urine pregnancy test or not using adequate contraception * Plan to receive any massage or manipulation directly over the leads or by the location of the IPG or treatments that involve sudden jerking motions of the torso at any time during the course of the study * Unresolved active litigation related to the pain condition being treated in the study * Currently involved in a worker's compensation claim * Unable to operate the SCS System