Spinal Cord Stimulation (SCS) Therapy Study

Inclusion Criteria: * At least 22 years of age or older at the time of informed consent * Implanted with a Medtronic RestoreSensor or RestoreUltra SCS system for an on-label indication at least 6 months for the treatment of chronic leg pain, with or without back pain * Implanted with one or more Medtronic leads located in the epidural space within the thoracic area * Receiving some level of pain relief with current SCS therapy * On a stable dose (no new, discontinued or changes in) of all prescription pain medications and willing to maintain or only decrease the dose of all prescribed pain medications * Read and understand English without assistance * Willing and able to comply with all study procedures, study visits, and be available for the duration of the study Exclusion Criteria: * Diagnosed with complex regional pain syndrome (CRPS), peripheral causalgia, or reflex sympathetic dystrophy (RSD), or causalgia * Has leg, knee, or foot pain unrelated to on-label indication for SCS therapy (for eg, arthritis, knee surgery, etc.) * Implanted with both a surgical and percutaneous lead * Implanted with a peripheral lead for subcutaneous or peripheral nerve stimulation * Has had any of the following procedures: * Neuroablative procedure within six months * Neurolytic block within two months * Injection therapy for pain within four weeks * Sympathetic block within two weeks * Has an active implanted device (besides RestoreUltra or RestoreSensor neurostimulator), whether turned ON or OFF * Pregnant or lactating, inadequate birth control, or at risk of pregnancy during this study * Has an untreated psychiatric comorbidity * Has serious drug-related behavioral issues * Has active malignancy or has been diagnosed with cancer and has not been in remission for at least one year * Has secondary gains which, in the opinion of the investigator, are likely to interfere with the study * Participating or planning to participate in another clinical trial while enrolled in this study