High-density Stimulation, High-frequency Stimulation, Spinal Cord Stimulation
Conditions
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.
Interventions
Patients in this group will receive sub-threshold high-frequency (aka 1200Hz) spinal cord stimulation for 2 weeks.
DEVICESham Stimulation
Patients in this group will receive receive sham spinal cord stimulation (aka no stimulation) for 2 weeks.
Sponsors
Case Western Reserve University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Intervention model description
All subjects underwent two weeks of conventional stimulation, followed by randomization to receive either subthreshold high-density (HD) or sham stimulation; this was followed by a crossover during which the participants who had received subthreshold HD stimulation were treated with sham and vice versa.
Eligibility
Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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 |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| High-Frequency Stimulation, Then Placebo 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 received sham spinal cord stimulation (1200 Hz at 0 V amplitude) for 2 weeks. | 2 |
| Placebo Stimulation, Then 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. | 2 |
| Total | 4 |
Baseline characteristics
| Characteristic | High-Frequency Stimulation, Then Placebo Stimulation | Placebo Stimulation, Then High-Frequency Stimulation | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 1 Participants | 0 Participants | 1 Participants |
| Age, Categorical Between 18 and 65 years | 1 Participants | 2 Participants | 3 Participants |
| Region of Enrollment United States | 2 participants | 2 participants | 4 participants |
| Sex: Female, Male Female | 2 Participants | 0 Participants | 2 Participants |
| Sex: Female, Male Male | 0 Participants | 2 Participants | 2 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 4 | 0 / 4 |
| other Total, other adverse events | 2 / 4 | 2 / 4 |
| serious Total, serious adverse events | 0 / 4 | 0 / 4 |
Outcome results
Primary
Visual Analog Pain Scale
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.
Time frame: 8 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| High-density Stimulation | Visual Analog Pain Scale | 2.29 units on a scale | Standard Deviation 0.41 |
| Placebo Stimulation | Visual Analog Pain Scale | 6.31 units on a scale | Standard Deviation 1.22 |
Secondary
Change in Brief Pain Inventory (BPI)
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)
Time frame: 8 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| High-density Stimulation | Change in Brief Pain Inventory (BPI) | -2.0625 units on a scale | Standard Deviation 1.21875 |
| Placebo Stimulation | Change in Brief Pain Inventory (BPI) | 1.21875 units on a scale | Standard Deviation 1.555819 |
Secondary
Change in SF-36
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.
Time frame: 8 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| High-density Stimulation | Change in SF-36 | -28.125 units on a scale | Standard Deviation 19.83001 |
| Placebo Stimulation | Change in SF-36 | 23.125 units on a scale | Standard Deviation 35.90352 |
Secondary
Number of Patients With Side Effects of Stimulation
Incidence of side effects of stimulation
Time frame: 8 weeks
Population: No subjects were randomized to the conventional spinal cord stimulation group
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| High-density Stimulation | Number of Patients With Side Effects of Stimulation | 2 participants |
| Placebo Stimulation | Number of Patients With Side Effects of Stimulation | 2 participants |
Secondary
Pain Vigilance and Awareness Questionnaire (PVAQ)
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.
Time frame: 8 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| High-density Stimulation | Pain Vigilance and Awareness Questionnaire (PVAQ) | 46.8 units on a scale | Standard Deviation 7.1 |
| Placebo Stimulation | Pain Vigilance and Awareness Questionnaire (PVAQ) | 51.5 units on a scale | Standard Deviation 6.4 |