Spinal Cord Burst Stimulation for Chronic Radicular Pain Following Lumbar Spine Surgery

Study Overview
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Brief Summary
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Spinal cord stimulation (SCS) is a widely applied therapy to treat chronic neuropathic pain, and one of the most common indications is persisting radicular neuropathic pain following lumbar spine surgery. In traditional SCS therapies, the objective has been to replace the pain sensation with paresthesia. The anticipation is that the electrical current alters pain processing by masking the sensation of pain with a comfortable tingling or paresthesia. Although patients mostly cope with paresthesia, a significant proportion reports that the sensation is unpleasant. 'Burst' SCS utilizes complex programming to deliver high-frequency stimuli. This SCS technique seems to provide paresthesia-free stimulation, resulting in better pain relief of low back and leg pain then traditional tonic stimulation. The widespread use of SCS has not been backed by solid evidence. The absence of placebo-controlled trials has long been an important point of criticism, but due to the nature of the intervention with sensation of paresthesia, studies with placebo control have so far not been considered possible. When 'burst' SCS is used the stimulation is often unnoticed by the patient, allowing comparison with placebo stimulation. The aim of this randomized double-blind sham-controlled crossover trial is to evaluate the efficacy of 'burst' spinal cord stimulation for chronic radicular pain following spine surgery.

Official Title
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Spinal Cord Burst Stimulation for Chronic Radicular Pain Following Lumbar Spine Surgery: A Randomized Double-blind Sham-controlled Crossover Trial

Conditions
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Back Pain With Radiation, Pain, Postoperative

Intervention / Treatment
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* Procedure: Burst Spinal Cord Stimulation
* Procedure: Sham spinal cord stimulation
* Device: SCS implant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Have undergone ≥1 back surgeries and developed chronic radicular pain that has remained refractory to non-surgical treatment for ≥6 months Minimum pain intensity of 5/10 on the leg pain NRS at baseline Successful two-week SCS testing period with tonic stimulation (≥2 points reduction in leg pain NRS from baseline). This means patients will experience paresthesia during the SCS trial period Mandatory assessment at the Multidisciplinary outpatient clinic for back-, neck- and shoulder rehabilitation, St. Olavs University Hospital Exclusion Criteria: Coexisting conditions that would increase procedural risk (e.g., sepsis, coagulopathy) History of laminectomy or posterior fusion at the thoracolumbar junction, where percutaneous electrode end tips are routinely placed. Abnormal pain behavior and/or unresolved psychiatric illness. Unresolved issues of secondary gain or inappropriate medication use.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Burst SCS<br>Burst Spinal cord stimulation. SCS system implanted and burst stimulation given | Procedure: Burst Spinal Cord Stimulation<br>* Burst stimulation utilizes complex programming to deliver high-frequency stimuli of a 40 Hz burst mode with 5 spikes at 500 Hz per spike delivered in a constant current mode<br>Procedure: Sham spinal cord stimulation<br>* No spinal cord stimulation is provided<br>Device: SCS implant<br>* a subcutaneously implantable pulse generator (pacemaker) for long-term therapy. The following system from Boston Scientific will be implanted: Precision NoviTM implantable pulse generator and InfinionTM CX 16-contact lead or LinearTM ST 8-contact lead.<br>|
| Sham Comparator: Sham SCS<br>Sham spinal cord stimulation. SCS system implanted but no stimulation given. | Procedure: Burst Spinal Cord Stimulation<br>* Burst stimulation utilizes complex programming to deliver high-frequency stimuli of a 40 Hz burst mode with 5 spikes at 500 Hz per spike delivered in a constant current mode<br>Procedure: Sham spinal cord stimulation<br>* No spinal cord stimulation is provided<br>Device: SCS implant<br>* a subcutaneously implantable pulse generator (pacemaker) for long-term therapy. The following system from Boston Scientific will be implanted: Precision NoviTM implantable pulse generator and InfinionTM CX 16-contact lead or LinearTM ST 8-contact lead.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in disease-specific functional outcome between active burst stimulation and placebo stimulation periods | measured with version 2.0 of the Oswestry disability index (ODI) that has been translated into Norwegian and tested for psychometric properties. The ODI questionnaire quantifies disability for degenerative conditions of the lumbar spine and covers intensity of pain, ability to lift, ability to care for oneself, ability to walk, ability to sit, sexual function, ability to stand, social life, sleep quality, and ability to travel. The index is scored from 0 to 100. Zero means no disability and 100 reflects maximum disability. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in generic health-related quality of life measured with the Euro-Qol-5D (5L) between active burst stimulation and placebo stimulation periods |  | 12 months | 
| Change from baseline in back pain between active burst stimulation and placebo stimulation periods | measured using numerical rating scales (NRS) | 12 months | 
| Change from baseline in leg pain between active burst stimulation and placebo stimulation periods | measured using numerical rating scales (NRS) | 12 months | 
| Change from baseline in daily physical activity between active burst stimulation and placebo stimulation periods | measured by use of a body-worn accelerometer (activPALs from PAL Technologies Ltd., Glasgow, United Kingdom) attached by a waterproof tape to the midpoint of the patients' anterior right thigh | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Lumbar Vertebrae, Surgery, Postoperational Complications, Spinal Cord Stimulation