To determine the effects of varying spinal cord stimulation programming parameters, including stimulation rate, on pain intensity.

This study compared the effects of high-rate subperception stimulation with the effects of low-rate subperception stimulation on pain intensity.

Inclusion Criteria:

• Chronic intractable pain of the trunk and/or limbs
• Documented history of trunk and/or limb pain of at least 180 days
• Average back pain intensity of 5 or greater on a 0-10 numerical rating scale during the 7-day period prior to the Screening Visit
• Pass study site's routine psychological/psychiatric evaluation within 180 days of the Trial Lead Insertion Visit
• If taking any medications for chronic pain, must be on a stable prescription during the 14-day period prior to the Trial Lead Insertion Visit and agree to continue on the same prescription throughout study participation
• Subject is willing and able to comply with all protocol-required procedures and assessments/evaluations
• Subject is able to independently read and complete all questionnaires and/or assessments provided in English
• 18 years of age or older when written informed consent is obtained
• Subject signs a valid, Institutional Review Board (IRB)-approved informed consent form (ICF) provided in English

Exclusion Criteria:

• Unable to operate the Precision Plus system
• Primary source of pain is cancer-related, pelvic, visceral, angina, or migraine
• Is a high surgical risk
• Is diabetic
• Is immunocompromised
• Currently on any anticoagulant medications that cannot be discontinued during perioperative period
• Untreated major depression or untreated generalized anxiety disorder
• Diagnosed with somatoform disorder, severe personality disorder, borderline personality disorder
• Diagnosed with any major psychiatric disorder not specifically listed in CE7 or CE8
• Currently diagnosed with cognitive impairment that would limit subject's ability to discern differences in pain severity, complete a pain diary, perform wound care
• Current abuse of alcohol or illicit drugs
• Subject requires Magnetic Resonance Imaging (MRI) while implanted with lead(s).
• Subject is participating (or intends to participate) in another drug or device clinical trial that may influence the data that will be collected for this study
• Subject has previously undergone a spinal cord stimulation trial or is already implanted with an active implantable device(s) to treat their pain (Implantable Pulse Generators (IPGs), implantable drug pump, etc.) or pacemaker or implantable cardiac defibrillator
• Patient is a woman who is not using adequate contraception, is pregnant or breastfeeding or intends to become pregnant during the course of the study (a urine pregnancy test must be performed within 28 days prior to the Trial Lead Insertion Visit in women of child-bearing potential and the test result documented)

Baseline measurements were taken for all enrolled subjects (n = 20), but 2 subjects randomized to first receive low rate stimulation withdrew prior to stimulation. Thus, 11 subjects in that group had baseline measurements, but only 9 of them received stimulation.

7-9 days

Trial lead insertion was on Day 0, followed by 2 study periods lasting 3-4 days each. Though 18 subjects started stimulation, 20 subjects enrolled and had procedures performed. Two subjects withdrew after attempted lead insertion but before stimulation. Thus, the "At Risk" population during trial lead insertion is reported as 20, not 18.