Placebo Effect In Spinal Cord Electrical Stimulation for Pain
ConditionChronic Postoperative Pain
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-70
SponsorSahlgrenska University Hospital
About this trial
Objective: To evaluate if spinal cord stimulation (SCS) performs better than placebo (no stimulation) in the long term to reduce persistent neuropathic leg pain refractory to medication and other conservative treatments in patients who have undergone lumbar spinal surgery.
Study design: Multicenter, double blind, randomized, sham-controlled trial.
After a positive SCS test trial, participants (18-70 years) will be implanted with a non-rechargeable SCS system providing active, subthreshold stimulation and followed for 12 months in a blinded cross-over design. The primary outcome measure is the difference in change in leg pain intensity scores using the Numeric Rating Scale (NRS) between a 3-month period with optimized subthreshold stimulation, and a 3-month period with no stimulation, as compared to baseline. Quality of life, physical functioning, sleep quality, return to work, and reduction in medication use will also be investigated.
Background: Up to 20% of patients who have undergone lumbar spinal surgery experience persistent back/leg pain leading to long-term reduction in functionality and quality of life. SCS is an established and safe, minimally invasive treatment for these patients when no further surgery is indicated and conservative therapies have been found to be ineffective. Placebo-controlled studies, comparing active and sham stimulation, were lacking until recently as traditional SCS relied on the patient feeling the stimulation (paresthesia). Technological progress with development of paresthesia-free stimulation forms now allows for the execution of placebo-controlled studies. A recent trial showing no significant difference in long-term effectiveness between active SCS and sham suffers from significant methodological shortcomings. This necessitates further sham-controlled studies to determine the effectiveness of SCS.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
History consistent with PSPS2 of at least 6 months after the last spinal surgery. The patient experienced no effect of conservative treatments and has been assessed as not eligible for further spinal surgery.
Patients between 18-70 years of age.
Average perceived pain intensity in one or both legs of 5 or more and average perceived pain intensity in the back of less than 3 measured with the validated 11-box NRS (0 no pain, 10 worst imaginable pain)
The patient should have been informed verbally and in writing about the study and should have provided informed written consent to participate.
Disqualifiers
Subject is unable to understand or operate the SCS device.
Subject currently has an active implantable device including pacemakers, spinal cord stimulator or intrathecal drug delivery system.
Ongoing coagulation disorder.
Ongoing abuse of alcohol, drugs, or prescription opioids.
Trial design
Design model
Crossover
Treatments tested in this trial
Spinal cord stimulation
DeviceStimulation off
Spinal cord stimulation
DeviceStimulation on
Treatment groups
50 Participants
are divided into 2 treatment groupsGroup A: No stimulationSham comparator 1 intervention
Group B: StimulationActive comparator 1 intervention
Trial outcomes
Primary outcomes
1
Comparison between active subthreshold spinal cord stimulation and sham stimulation in reducing neuropathic leg pain
The difference in change in neuropathic leg pain intensity scores measured by the numeric rating scale (NRS) questionnaire using a 0-10 scale between a 3-month period with subthreshold stimulation and a 3-month period with sham stimulation, as compared to baseline. Zero means no pain and 10 means the worst pain imaginable with higher scores indicating worse outcome.
Time frame
Baseline and 3+3 monthsSecondary outcomes
1
Comparison between active subthreshold spinal cord stimulation and sham stimulation
Physical functioning measured using the Oswestry Disability Index (ODI) questionnaire with an index range of 0-100. Zero is equated with no disabiliy and 100 is the maximum disability possible with higher scores indicating a worse outcome.
Time frame
Baseline and 3, 6 and 12 months2
Comparison between active subthreshold spinal cord stimulation and sham stimulation
• Quality of life measured using the EuroQoL-5 Dimension-5 Levels (EQ-5D-5L) questionnaire assigning values of 1 (no problems) to 5 (extreme problems) and summing these values cross five items, resulting in a score from 5 (no problems on any dimensions) to 25 (extreme problems on all dimensions). Higher scores mean worse outcome.
Time frame
Baseline and 3, 6 and 12 months3
Comparison between active subthreshold spinal cord stimulation and sham stimulation
Sleep quality measured using the Pittsburgh Sleep Quality Index (PSQI) seven component questionnaire with each component scoring from 0 (no difficulty) to 3 (severe difficulty). The component scores are summed to produce a global score (range 0-21) where higher scores indicate worse sleep quality.
Time frame
Baseline and 3, 6 and 12 months4
Comparison between active subthreshold spinal cord stimulation and sham stimulation
Medication use
Time frame
Baseline and 3, 6 and 12 monthsSponsors and contacts
Click on the lead sponsor to view all of their trials.
Sahlgrenska University Hospital
Lead sponsor
Rijnstate Hospital
Collaborator
Source ClinicalTrials.gov