High Frequency Stimulation Trials in Patients With Precision Spinal Cord Stimulator System (HFSCS)

Single Blinded, Randomized Control Trial of High Frequency Stimulation in Subjects With Precision® Spinal Cord Stimulator System to Assess Efficacy and Preferability in Back and Extremity Pain Relief

Study designed to compare the conventional stimulation programming versus the high frequency stimulation programming of the spinal cord stimulator for subjects who already have a spinal cord stimulator.

Subject with Precision models of spinal cord stimulators will be invited to take part in the study that will compare the high frequency stimulation versus low frequency stimulation to look for any changes in efficacy, and preferability between high and low frequency stimulation program for the spinal cord stimulator (SCS) system. The study is designed as 7 week study that can take up to 9 weeks per subject. 7 weeks are divided into 3 segments. First segment will be 3 weeks of spinal cord stimulation followed by second segment of wash off period, which will take 1 week (7 days), then the last segment with 3 weeks of spinal cord stimulation. At the end of each segments, there will be a follow up visits. Each follow up visits can occur up to 5 business days after the follow up due date for post spinal cord stimulation follow ups, and up to 3 business days after the follow up due date for the post wash off visit. At each visits, including baseline, subject will be asked to answer Numeric Pain Rating Scale (NPRS), Oswestry Disability Index (ODI), and Patients Global Impression of Change (PGIC) to assess interval effect of the programming parameter for the spinal cord stimulator. Visit schedule and assessment summary: Visit 1: Screening and Baseline Review inclusion and exclusionary criteria (I&E) Informed Consent Demographics, Medical History Physical examination, Vital signs. Randomization (A, or B) and programming of devices according to randomization Baseline questionnaires Numeric Pain Rating Scale (NPRS) to measure the pain experienced by the subject over 1 week prior to enrolling in the study. this will include best pain, worse pain, and average pain as well as pain at the time of enrollment. Oswestry disability index (ODI) will measure the average disability caused by the painful condition approximately 3 weeks prior to the enrollment in to the study. Subject will be asked on 10 different categories of activities of daily living. They are: pain intensity, personal care, lifting, walking, sitting, standing, sleeping, sex life, social life, and traveling. Patients Global Impression of Change (PGI-C) will be asked to assess the subject's impression of their painful condition, since the implanting of the spinal cord stimulator. Concomitant medications Visit 2: (end of 3 week assessments, + 5 days) End of first treatment period Interim Questionnaires: NPRS: We will measure pain experienced by the subject over 3 weeks since the last research visit (visit 1),prior to visit 2. This will include best pain, worse pain, and average pain as well as pain at the time of enrollment. Oswestry disability index will measure the disability caused by the painful condition since last visit of the study (visit 1), which covers 3 weeks of duration after the last research visit. Subject will be asked on 10 different categories of activities of daily living. They are: pain intensity, personal care, lifting, walking, sitting, standing, sleeping, sex life, social life, and traveling. PGI-C will be asked to assess the subject's impression of their painful condition, since the last visit of the study (visit 1), which covers 3 weeks of duration since the last research visit, prior to visit 2. Device Interrogation and turn off SCS for 7 to 10 days Start wash off period for 7 to 10 days Review Adverse Events (AE) and Concomitant medications (Con meds) Visit 3: (end of wash off period, +3 days) Beginning of second treatment period Questionnaires: NPRS to measure the pain experienced by the subject over 1 week since visit 2, prior to visit 3, this will include best pain, worse pain, and average pain as well as pain at the time of enrollment. Oswestry disability index will measure the disability caused by the painful condition 1 week since last visit 2, prior to the visit 3. Subject will be asked on 10 different categories of activities of daily living. They are: pain intensity, personal care, lifting, walking, sitting, standing, sleeping, sex life, social life, and traveling. PGI-C will be asked to assess the subject's impression of their painful condition, during the last 1 week since visit 2, prior to visit 3. Device interrogation and programming; start of next treatment period. Review AE and Con meds. Visit 4: (end of 3 week assessment +5 days) End of Treatment End of second treatment period. End of treatment Questionnaires: NPRS: We will measure pain experienced by the subject over 3 weeks since the last research visit (visit 3) prior to visit 4. This will include best pain, worse pain, and average pain as well as pain at the time of enrollment. Oswestry disability index will measure the disability caused by the painful condition since last visit of the study, which covers 3 weeks of duration after the last research visit (visit 3). Subject will be asked on 10 different categories of activities of daily living. They are: pain intensity, personal care, lifting, walking, sitting, standing, sleeping, sex life, social life, and traveling. PGI-C will be asked to assess the subject's impression of their painful condition, since the last visit of the study, which covers 3 weeks of duration since the last research visit (visit 3), prior to visit 4. Device Interrogation and re-programming if necessary. Review AE's and Con meds

Spinal cord stimulation, Chronic pain, Chronic low back pain, Radiculopathy, Complex Regional Pain Syndrome (CRPS), High Frequency stimulation

Subjects assigned to treatment group A will begin the 7 week study with high frequency stimulation for first 3 weeks of the study. After first 3 weeks, subject will return to clinic to turn off the SCS device, and will start 7-10 days of wash off period. At the end of the wash off period, subject will return to clinic and have the SCS device turned on to have it programmed to deliver the low frequency stimulation for the next 3 weeks. At the end of the 7th week, the subject will return for final end of treatment visit for conclusion of the study.

Subjects assigned to treatment group B will begin the 7 week study with low frequency stimulation for first 3 weeks of the study. After first 3 weeks, subject will return to clinic to turn off the SCS device, and will start 7-10 days of wash off period. At the end of the wash off period, subject will return to clinic and have the SCS device turned on to have it programmed to deliver the high frequency stimulation for the next 3 weeks. At the end of the 7th week, the subject will return for final end of treatment visit for conclusion of the study.

Implanted pulse generator of a spinal cord stimulator will programmed to deliver high frequency stimulation for pain relief. For our purposes, high frequency stimulation will be defined as 1000 hertz.

Implanted pulse generator of a spinal cord stimulator will programmed to deliver low frequency stimulation for pain relief. Low frequency stimulation will be defined as conventional stimulation pulse generator programming.

Digital pain rating system that scores patient's subjective pain rating from 0 to 10; with greater number indicating progressively worsening pain. NPRS were measured at baseline (visit1), and at each follow ups visits at visit 2, 3 and 4. Visit 2 and 4 captured post treatment (either 1000 Hz or standard stimulation depending on the randomization) results, and visit 3 captured NPRS after the wash off from the spinal cord stimulation.

ODI is a outcome metrics that is design to assess the severity of disability based on 10 activity categories. ODI is based on 0 to 100% scale, where larger percentage implies worse disability. (There are 5 categories: 0-20%: Minimal disability, 21-40%: Moderate disability, 41-60%: Severe disability, 61-80%: Crippled. 81-100%: Either bed bound or exaggerating symptoms). ODI were measured at baseline (visit1), and at each follow ups visits at visit 2, 3 and 4. Visit 2 and 4 captured post treatment (either 1000 Hz or standard stimulation depending on the randomization) results, and visit 3 captured NPRS after the wash off from the spinal cord stimulation.

PGIC is a 7-point scale that requires study subjects to rate the severity of their illness or medical condition after a specific treatment. 1: No change, 2: Almost the same, 3: A little better, 4: Somewhat better, 5: Moderately better, 6: Better, 7: A great deal better. Study subjects were asked to report their impression of changes at baseline visit, visit 2 through 4.

At the conclusion of the study, subjects were asked to report which spinal cord stimulation modes they preferred. Subjects were presented with two boxes (1000 Hz. stimulation and Standard stimulation) and asked to check one.

Inclusion Criteria: Subject must be 18 years and older, and younger than 70 years of age. Subject has had a Precision® spinal cord stimulator system implanted for chronic painful condition. Subject pain scores >5 on NPRS Exclusion Criteria: Currently diagnosed with cognitive impairment, or exhibits any characteristic, that would limit study candidate's ability to assess pain Unstable medical or psychiatric illness Lifetime history of psychosis, hypomania, or mania. Epilepsy, or dementia Substance abuse in the last 6 months Pregnant or breastfeeding Not on contraception for those of childbearing age. (Barrier methods, oral contraception, hormone injections, or surgical sterilization) Treatment with investigational drug within 30 days of screening. Concomitant medication exclusions consisting of medications or herbal agents with central nervous system (CNS) effects with exception of episodic use of sedating antihistamines

No individual participants data will be shared with anyone other than study staff for analysis purposes.

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