Please select the eligibility criteria that correspond to the clinical trial below.
Title: Prospective, Randomized Study Comparing Conventional, Burst And High Frequency (HF) Spinal Cord Stimulation (SCS) in Refractory Failed Back Surgery Syndrome (FBSS) Patients After a 32-contact Surgical Lead Implantation
Brief Summary: Chronic Back and/or Leg Pain (CBLP) after spinal surgical procedures, a condition commonly labelled Failed Back Surgery Syndrome (FBSS), affects between 15% and 40% of patients after a spine surgery. Treatment of this chronic condition by further operation or medical management has a heavy financial impact on health care systems.

Many studies have demonstrated the efficacy and economic value of Spinal Cord Stimulation (SCS) for chronic neuropathic pain, and randomized controlled trials (RCTs) have shown SCS to be a clinically effective adjunct to medical management. SCS has the advantages of being reversible and less invasive than surgery and may cause fewer issues over time than long-term pharmacological treatments.

Despite variable levels of success in the literature, approximately 30-55% of the patients treated with traditional SCS for neuropathic pain disorders will not receive adequate long term pain relief. Therefore, technical SCS system refinements, as well as new techniques have emerged.

Two new stimulation waveforms based on traditional SCS technology have appeared to further optimize the outcome for specific painful conditions;

* Burst stimulation mode: which generates constant-current stimuli with 5 spikes at 500 Hz per burst and pulse width and interspike intervals of 1 ms.
* High-frequency stimulation (from 1 to 10 kHz) mode.

Several studies have demonstrated the potential interest of these 2 new waveforms to treat FBSS patients compared to traditional SCS.

The Precision Spectra™ system allows MultiWave Technology by offering a broad spectrum of waveform options (from Tonic Conventional Stimulation (TCS), BURST stimulation to High Frequency stimulation (HF)).

To date, literature data comparing these 3 stimulation patterns is lacking but it is suggested the pain relief in some of non-responsive patients can be "recaptured" by increasing the SCS frequency to 500 Hz by BURST stimulation or beyond by HF stimulation. It seems important to conduct RCT in crossover, thanks to the new Precision SCS Stimulator, to compare the effects of these 3 different SCS modalities in FBSS patients and to determine which concept is the most effective in terms of pain reduction and energy consumption.


Options:
A: Inclusion Criteria:

1. Occurrence of chronic pain in the lumbosacral region, as well as unilateral or bilateral leg pain.
2. Prior lumbar surgery in medical history.
3. Diagnosed with neuropathic pain in the lower extremities and graded as probable neuropathic pain or definite neuropathic pain according International Association for the Study of Pain (IASP) criteria.
4. Patient report largely unchanged pain condition last 6 months.
5. Patient has undergone a 7 day SCS trial with epidural burst stimulation with the following results:

   1. At least 75% coverage of the painful area of tonic stimulation before start of burst trial stimulation.
   2. At least 50% reduction in pain intensity, measured via BPI, item 5 from baseline of trial to end of trial period.
6. The patient is ≥ 18 years of age and \< 60 years of age.
7. The patient must willingly participate in all parts of the study, as well as having the ability to complete the entire study plan.
8. Patient must certify that he / she understands the study plan, as well as voluntarily sign informed consent to participate in the study.
9. Must be able to sit still for a minimum of 45 minutes and be able to follow restrictions related to the PET survey.

Exclusion Criteria:

1. The patient has other current pain conditions than back and leg pain after back surgery.
2. The patient is treated with opioids exceeding 80 milligrams of Morphine per day or is considered at risk for development of problematic opioid use.
3. The patient suffers from an untreated depression or anxiety.
4. The patient can not complete the study plan.
5. The patient is unable to read or write Swedish.
6. The patient is currently participates in another clinical trial.
7. A history of previous PET scan or other substantial radiation dose in the last 5 years.
8. The patients is suffering from claustrophobia.
9. Ongoing pregnancy or planned pregnancy during study time.
10. The patient has contraindications for arterial catheterization.
11. The patient is previously treated with spinal cord stimulation.
B: Inclusion Criteria:

* Age ≥ 18 years or ≤ 80 years.
* Subject has FBSS and does not require further surgery. For the purposes of this study, FBSS is defined as persistent or recurrent low back and leg pain of at least 6 months duration following at least one decompression and/or fusion procedure.
* Subject has persistent low back and leg pain despite other treatment modalities (pharmacological, surgical, physical, or psychological therapies) that have been tried and did not prove satisfactory or are unsuitable or contraindicated for the subject.
* Average global pain is ≥ 50 mm as assessed by the baseline VAS.
* With significant back, with mean intensity on a back pain VAS ≥ 50 mm (mean daily VAS score calculated on 5 consecutive days).
* Meeting the criteria for spinal cord stimulation test according to HAS guidelines (multidisciplinary consultation, psychological assessment, etc.).
* Subject is a candidate for SCS.
* Absence of active psychosis or history of serious psychotic illness requiring hospitalisation.
* Understands and accepts the constraints of the study.
* Free subject, not under temporary or permanent guardianship and not subject to subordination.
* Patients covered by French national health insurance.
* Patients who have given their written consent to the study after having received clear information.

Exclusion Criteria:

* Age \< 18 years or \> 80 years
* Subject is or has been treated with SCS, subcutaneous or peripheral nerve stimulation, an intrathecal drug delivery system, requires back surgery at the location related to his/her original back pain complaint or experimental therapies.
* Cause of low back pain accessible to etiological "mechanical" surgical treatment (discogenic low back pain, vertebral instability, spinal deformity, etc.).
* Subject had most recent back surgery less than 6 months ago.
* Presenting a surgical, anaesthetic or psychiatric contraindication to implantation of a spinal cord stimulation system.
* Based on the opinion of the principal or sub-investigator, the subject is unable to operate the SCS equipment.
* Subject has a life expectancy of less than 24 months beyond study enrolment.
* Absence of signature of the informed consent form.
* Patients not covered by French national health insurance.
* Subjects requiring closer protection, i.e. minors, pregnant women, nursing mothers, subjects deprived of their freedom by a court or administrative decision, subjects admitted to a health or social welfare establishment, major subjects under legal protection, and finally patients in an emergency setting.
* Pregnant women, nursing mothers, women of childbearing potential not using effective contraception (hormonal/barrier: oral, parenteral, percutaneous, implantable, intrauterine device, or surgical: tubal ligation, hysterectomy, total ovariectomy).
C: Inclusion Criteria:

* Aged from 18 to 80 years
* Presence of FBSS ≥ 3 months after one or several spine surgery
* Presence of back and leg pain with documented neuropathic component (DN4)
* Having failed well conducted conservative treatment
* Meeting the criteria for a test of spinal cord stimulation as recommended by HAS (multidisciplinary consultation, psychological evaluation
* Presence of uni-or bilateral radicular pain with severe intensity, VAS score greater than or equal to 50/100 (daily VAS mean on 5 consecutive days).
* Presence of associated back pain, as related to type "bar" or "tender points"
* Understanding and accepting the constraints of the study
* Covered by a French Health Insurance plan or benefiting of such as a third party in agreement with the French law (Huriet law n°88.1138 and modifications) on biomedical research
* Has given written consent to the study after receiving clear information.
* Absence of psychosis or evolutionary history of severe psychosis requiring hospitalization.
* Absence of progressive malignancy

Exclusion Criteria:

* Age \< 18 and \> 80 years
* Accessible because of back pain surgery 'mechanical' causal (discogenic back pain, spinal instability, spinal deformation)
* Presence of surgery, anesthetic and psychiatric contraindication for spinal cord stimulation system implantation
* Absence of informed consent signature
* Women of childbearing without effective contraception (hormonal / mechanical: oral, injectable, transdermal, implantable, intrauterine device or surgical: tubal ligation, hysterectomy, oophorectomy total) or breastfeeding.
* Subject not covered by a French Health Insurance plan or not benefiting of such as a third party
* Subject receiving enhanced protection: minors, pregnant women, nursing women, persons deprived of liberty by a judicial or administrative decision, adults under legal protection, and finally patients in emergency situations.
D: Key Inclusion Criteria:

1. Have been diagnosed with chronic, refractory axial low back pain with a neuropathic component and are not eligible for spine surgery
2. Have not had any surgery for back or leg pain, or any surgery resulting in back or leg pain
3. Qualifying pain score
4. Be on stable pain medications, as determined by the Investigator
5. Be willing and capable of giving informed consent
6. Be willing and able to comply with study-related requirements, procedures, and visits
7. Be capable of subjective evaluation, able to read and understand written questionnaires in the local language and are able to read, understand and sign the written inform consent

Key Exclusion Criteria:

1. Have a diagnosed back condition with inflammatory causes of back pain, serious spinal pathology and/or neurological disorders
2. Have a medical condition or pain in other area(s), not intended to be treated in this study
3. Any diagnosis or known condition that can impact reporting of study outcomes as determined by the Investigator
4. Be benefitting within 30 days prior to enrollment from an interventional procedure to treat back and/or leg pain
5. Have any addictions as determined by the Investigator
6. Have an existing drug pump and/or SCS system or another active implantable device such as a pacemaker
7. Have prior experience with neuromodulation devices
8. Other general exclusions applicable for SCS devices
9. Be involved in an injury claim under current litigation
10. Have a pending or approved worker's compensation claim

Answer: B