Plain English Summary
Background and study aims
Back pain is a common condition which affects most people at some point in their lives. In some people, back pain can be so severe that the only effective treatment is surgery. If this is the case, the surgery usually aims to either reduce pressure on a nerve that is compressed or to stabilise a painful joint or disc in the back, depending on the underlying cause of the back pain. Failed back surgery syndrome (FBSS) is a general term used to describe patients who have not had a successful result after surgery on their back or spine and continue to experience pain after the procedure. The Nevro Senza SCS system is device which is implanted in the back to help relieve severe back pain by stimulating the spinal cord. Unlike traditional spinal stimulation devices, the Senza system delivers high frequency stimulation at low amplitudes, and so provides pain relief without a tingling sensation. The aim of this study is to learn more about how to further improve the Senza treatment by investigating aspects such as the stimulation settings and its effect on pain perception.
Who can participate?
Patients aged over 18 with predominant back pain after a failed back surgery
What does the study involve?
Participants undergo a trial of Spinal Cord Stimulation at 10 kHz (HF10 Therapy) as per the center’s usual practice. Successfully trialed participants get a permanent device implanted as per center’s routine clinical practice. During the study the stimulation settings are adjusted and changes in pain perception, if any, are documented. During this period, the effect of SCS on back pain is evaluated. The participants attend regular clinic visits to complete questionnaires, and to provide feedback on their pain perception.
What are the possible benefits and risks of participating?
Participants may benefit from the SCS system to relieve their back pain. There are no direct risks of taking part in this study, although the general risks of having a spinal stimulation device in place apply.
Where is the study run from?
1. AZ Nikolaas Multidisciplinary Center (Belgium)
2. AZ Delta Multidisciplinary Center (Belgium)
When is the study starting and how long is it expected to run for?
March 2016 to December 2018
Who is funding the study?
Nevro Corp (USA)
Who is the main contact?
Pain perception evaluation with paresthesia independent spinal cord stimulation therapy
The aim of this study is to assess the pain perception in HF10™ electrical stimulation delivered to the spinal cord in subjects with chronic, intractable back pain as per the center's routine practice.
AZ Delta Commissie Medische Ethiek, 12/07/2016, ref. B117201628681
Multicenter prospective interventional randomized clinical study
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Failed back surgery syndrome
Eligible subjects with predominant back pain after a failed back surgery will undergo a trial of Spinal Cord Stimulation (SCS) at 10 kHz (HF10 Therapy) as per the center’s usual practice. Successfully trialed subjects will get a permanent device implanted as per center’s routine clinical practice. During the study the stimulation settings will be adjusted and changes in pain perception, if any, will be documented. During this period, the effect of SCS on back pain will be evaluated. The participants will attend regular clinic visits to complete questionnaires, and to provide feedback on their pain perception.
Primary outcome measures
This study is statistically not powered for a specific efficacy hypothesis test. See section Study Hypothesis.
Secondary outcome measures
1. Back pain intensity assessed by numeric rating scale (NRS) at baseline, at the end of the trial and at post-IPG monthly follow-up visits (1, 2, 3, 4, 5 and 6 months)
2. Leg pain intensity assessed by NRS at baseline, at the end of the trial and at post-IPG monthly follow-up visits (1, 2, 3, 4, 5 and 6 months)
3. Pain quality assessed by SF-MPQ at baseline, at the end of the trial and at post-IPG 3 and 6 month follow-up visits
4. Neurological assessment at baseline and at post-IPG 3 month follow-up visit
5. Level of catastrophic thinking assessed by the Pain Catastrophizing Scale – PCS at baseline, at the end of the trial and at post-IPG 3 and 6 month follow-up visits
6. Emotional mood assessed by the State Trait Anxiety Inventory – STAI Y1-Y2 at baseline, at the end of the trial, and at post-IPG follow-up visits
7. Assessment of the subject’s condition and device use during follow-up, performed during the Weekly Telephone Interview (NRS pain, physical activity, medication use, adverse events, device usage)
8. Depression assessed by the Beck Depression Inventory – BDI-II at baseline, at the end of the trial, and at post-IPG 3 and 6 month follow-up visits
9. Assessment of the subject’s expectation with therapy assessed by NRS rating at enrolment
10. Assessment of the subject’s fulfillment of his expectation at the end of the trial and post-IPG monthly follow-up visits (1, 2, 3, 4, 5 and 6 months), assessed by NRS rating
11. General state of health assessed by the Patient Global Impression of Change instrument - PGIC at baseline, at the end of the trial and at post-IPG 3, 4 and 6 month follow-up visits
12. General state of health assessed by the Clinician Global Impression of Change instrument - CGIC at baseline, at the end of the trial and at post-IPG 3, 4 and 6 month follow-up visits
13. Assessment of medication usage at every visit
14. Assessment of rescue medication usage during post-IPG monthly follow-up visits (1, 2, 3, 4, 5 and 6 months)
15. Assessment of subject's satisfaction with therapy and device at the 3 and 6 month follow-up visits
16. Incidence of unanticipated adverse device effects (UADEs) at every visit
Overall trial start date
Overall trial end date
Participant inclusion criteria
1. Diagnosed with failed back surgery syndrome with predominant back pain
2. Average back pain intensity of ≥ 5 out of 10 on the Numeric Rating Scale (NRS) at enrollment
3. An appropriate candidate for Spinal Cord Stimulation as per the Belgian regulations
4. An adult (≥ 18 years of age) at time of enrollment
5. Evaluated at the investigational site at least once prior to screen for the pain condition related to the study
6. Willing and capable of giving written informed consent prior to any investigational related procedure
7. Willing and able to comply with study-related requirements, assessments and visits
8. Capable of subjective evaluation, able to read and understand written questionnaires, and able to read, understand and sign the written inform consent (Dutch and French)
9. Adequate cognitive ability to use a patient external trial stimulator and recharger as determined by the Investigator
10. An appropriate candidate for the surgical procedures required in this study based on the clinical judgment of the implanting physician and if applicable per the local regulations
11. On stable pain medications, as determined by the Investigator, for at least 4 weeks prior to the baseline visit
12. A stable physical activity level, as determined by the Investigator and activity diary, for at least 2 weeks prior to the baseline visit
Target number of participants
Participant exclusion criteria
1. Using an daily opioid dose of >60mg oral morphine equivalents (meq) or daily >25 µg/hr transdermal fentanyl
2. A medical condition or pain in other area(s), not intended to be treated with SCS, that could interfere with study procedures, accurate pain reporting, and/or confound evaluation of study endpoints
3. Evidence of an active disruptive psychological or psychiatric disorder or other known condition significant enough to impact perception of pain, compliance of intervention and/or ability to evaluate treatment outcome, as determined by a psychologist
4. A current diagnosis of a progressive neurological disease such as multiple sclerosis, chronic inflammatory demyelinating polyneuropathy, rapidly progressive arachnoiditis, rapidly progressive diabetic peripheral neuropathy, brain or spinal cord tumor, or severe/critical spinal stenosis
5. A visceral pain in the area being treated
6. A current diagnosis of a coagulation disorder, Complex Regional Pain Syndrome (CRPS), bleeding diathesis, progressive peripheral vascular disease or uncontrolled diabetes mellitus
7. A diagnosis of scoliosis that precludes lead placement
8. Recent evidence (imaging or letter neurosurgeon) of spinal instability requiring fusion (imaging such as flexion/extension films of lumbar spine is required for this determination and must have been done within the past 6 months)
9. Pain that is significantly exacerbated by activity or significantly alleviated by rest
10. Benefiting within 30 days prior to enrollment from an interventional procedure and/or surgery to treat back and/or leg pain
11. An existing drug pump and/or SCS system or another active implantable device (switched on or off) such as a pacemaker or other SCS devices
12. Prior experience with SCS
13. A condition currently requiring or likely to require the use of MRI in the trunk
14. Metastatic malignant disease or active local malignant disease
15. A life expectancy of less than 1 year
16. An active systemic or local infection
17. Pregnant (if female and sexually active, subject must be using a reliable form of birth control, be surgically sterile or be at least 2 years post-menopausal)
18. Within 6 months of enrollment a significant untreated addiction to dependency producing medications or have been a substance abuser (including alcohol and illicit drugs)
19. Limited physical activity not due to back pain (due to e.g. knee arthrosis, arthroplasty)
20. Concomitantly participating in another clinical study, or planned to be enrolled in another clinical study and/or data collection
21. Involved in an injury claim under current litigation
22. A pending or approved worker’s compensation claim
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
AZ Nikolaas Multidisciplinary Center
Trial participating centre
AZ Delta Multidisciplinary Center
Nevro Corp (USA)
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
1. Planned presentation of results to international congresses from the end of 2017
2. Planned publication in a peer-reviewed journal from the start of 2018
Intention to publish date
Participant level data
To be made available at a later date
Results - basic reporting