Direct Comparison of Spinal Cord Stimulator Parameter Settings

Not Applicable

Completed

Conditions: Spinal Cord Stimulation
High-density Stimulation
High-frequency Stimulation

Interventions: Device: High-frequency stimulation
Device: Sham Stimulation

Registration Number: NCT05283863

Lead Sponsor: Case Western Reserve University

Brief Summary: (Primary)

1. To compare the clinical effects and side effects of two different stimulation strategies that do not produce any sensory percept (1000 Hz and placebo) on clinical benefit for electrodes implanted for chronic pain as measured by the Visual Analog Pain Scale for back and leg pain, the Brief Pain Inventory, the 36-Item Short Form Survey (SF-36), and the Pain Vigilance and Awareness Questionnaire.

(Secondary)

2. To compare the clinical effects of the subthreshold (paresthesia-free) stimulation patterns with conventional (paresthesia-producing) stimulation patterns to evaluate the necessity of paresthesias and current amplitudes on clinical benefit for pain.

3. To identify the ability of subthreshold high-frequency to improve axial pain or the affective component of pain.

Detailed Description: This is a prospective, randomized, double-blind study of different stimulation patterns in patients undergoing implantation of neurostimulator systems for chronic medically intractable neuropathic pain. Research participants will be individuals who have undergone implantation of neurostimulator electrodes into the spinal column or peripheral nervous system for clinical treatment of neuropathic pain. All patients will already have undergone empiric programming of the stimulator using conventional settings (typically 40-60 Hz, 350-450 usec pulse width). However, other stimulation parameters, including high-frequency stimulation, are also feasible and FDA-approved using the implanted device, and it is possible to do this without producing a sensory percept, which makes it possible to test efficacy in a double blind manner. For this study, two different stimulation parameters will be tested during four two-week periods: 1000 Hz and placebo. Clinical response and side effect profile for each setting will be measured.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 4

Inclusion Criteria

Age 18-75 years
Diagnosis of chronic neuropathic pain for which placement of electrodes into the spinal column is planned for clinical indications (failed back surgery syndrome, peripheral neuropathy or complex regional pain syndrome)
History of implantation of spinal cord stimulation system with rechargeable implanted neurostimulator

Exclusion Criteria

Significant dementia or other condition preventing informed consent by the patient.
Current drug or alcohol abuse or dependence.
Uncontrolled depression or anxiety or failure to pass psychological screening for spinal cord stimulation.
Inability or unwillingness to cooperate with clinical testing.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
High-Frequency Stimulation, Then Placebo Stimulation	High-frequency stimulation	Participants first receive sub-threshold high-frequency spinal cord stimulation (1200 Hz frequency, 200 μsec pulse width, and an amplitude 90% of the threshold for detection of a sensory percept) for 2 weeks. After a 2-week washout period, they then receive sham spinal cord stimulation (1200 Hz at 0 V amplitude) for 2 weeks.
Placebo Stimulation, Then High-Frequency Stimulation	Sham Stimulation	Participants first receive sham spinal cord stimulation (1200 Hz at 0 V amplitude) for 2 weeks. After a 2-week washout period, they then receive sub-threshold high-frequency spinal cord stimulation (1200 Hz frequency, 200 μsec pulse width, and an amplitude 90% of the threshold for detection of a sensory percept) for 2 weeks.
Placebo Stimulation, Then High-Frequency Stimulation	High-frequency stimulation	Participants first receive sham spinal cord stimulation (1200 Hz at 0 V amplitude) for 2 weeks. After a 2-week washout period, they then receive sub-threshold high-frequency spinal cord stimulation (1200 Hz frequency, 200 μsec pulse width, and an amplitude 90% of the threshold for detection of a sensory percept) for 2 weeks.
High-Frequency Stimulation, Then Placebo Stimulation	Sham Stimulation	Participants first receive sub-threshold high-frequency spinal cord stimulation (1200 Hz frequency, 200 μsec pulse width, and an amplitude 90% of the threshold for detection of a sensory percept) for 2 weeks. After a 2-week washout period, they then receive sham spinal cord stimulation (1200 Hz at 0 V amplitude) for 2 weeks.

Primary Outcome Measures

Name	Time	Method
Visual Analog Pain Scale	8 weeks	Assessment of overall degree of back and leg pain during each phase of stimulation (ie conventional baseline stimulation, high-density stimulation, conventional "washout" stimulation, and sham stimulation). Scores range from 0 - 100, with a higher score indicating more pain.

Secondary Outcome Measures

Name	Time	Method
Change in Brief Pain Inventory (BPI)	8 weeks	The BPI assesses pain at its "worst," "least," "average," and "now" (current pain). Each item is rated on a scale of 0 - 10 with 10 indicating higher levels of pain. For purposes of this outcome measure, we focused on "now" (current pain)
Change in SF-36	8 weeks	The SF-36 is a measure of quality of life, with scores ranging from 0 - 100, with higher scores indicating a higher quality of life.
Pain Vigilance and Awareness Questionnaire (PVAQ)	8 weeks	The PVAQ is a measure of vigilance and attention to pain. Total scores can range from 0 to 90, with higher scores indicating more pain vigilance.
Number of Patients With Side Effects of Stimulation	8 weeks	Incidence of side effects of stimulation