Spinal Cord Stimulation in Patients With Post-Laminectomy Syndrome in Testing Phase

Study Overview
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Brief Summary
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Traditionally, pain relief through spinal cord stimulation has been associated with the appearance of paresthesia in the affected area. Several parameters are set to maximize the overexposure zone, such as frequency,and pulse width. Although this technique has improved pain in many patients, paresthesia itself can be uncomfortable. Traditionally, the occurrence of paresthesias has been considered to be a predictor of success in pain elimination, while the non-occurrence of paresthesias would indicate failure. So far, few studies have reported pain relief below the threshold of onset of paresthesia. Some clinical trials for pathologies other than the one considered in this study have achieved relief below the threshold by reducing the amplitude of the stimulus. Recently, however, it has been observed in a pilot study that, by increasing the frequency of spinal cord stimulation to 1 kilohertz, it is possible to significantly improve pain relief compared to less frequent conventional stimulation based on the occurrence of paresthesias. A recent review by the Cochrane Library concluded that conventional spinal cord stimulation for pain relief of Failed Back Surgery Syndrome (or FBSS) requires further clinical studies and better designs to demonstrate its superiority over other therapeutic options. Therefore, although spinal cord stimulation is accepted by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA), new techniques are being introduced that offer better results in terms of pain relief. Among these techniques, there is the high frequency mode, which allows avoiding the annoying sensation of paresthesia that substitutes pain with the conventional technique. In order to provide greater rigour and scientific quality, the present study is proposed, in which the conventional spinal cord stimulation (CME) technique (control branch or CME) is compared with paresthesias and a standard frequency (60 hertz) with a high frequency (1000 hertz) EVOLVE system (Evolve workflow - standardized guidance to simplify the trial and implant experience and optimize patient outcomes) (experimental branch or EME) by means of a design with a high degree of scientific evidence, randomising the global sample of patients to each of the two branches of stimulation in the study (blind to the patient) and crossing the branches after a period of washing

Official Title
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Randomized, Single-blind, Multicenter, Crossover, Controlled Clinical Trial to Compare Difference on the Visual Analogue Scale With Two Modes of Spinal Cord Stimulation in Patients With Post-Laminectomy Syndrome in Testing Phase

Conditions
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Laminectomy, Post-laminectomy Syndrome, Spinal Cord Syndrome, Failed Back Surgery Syndrome

Intervention / Treatment
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* Device: spinal cord stimulation conventional
* Device: spinal cord stimulation experimental


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients over 18 years of age. Patients with FBSS syndrome with leg pain or leg and back pain. Get a score on the visual analogue scale (VAS) ≥ 7. Have received medical pharmacological treatment for at least 6 months after back surgery. The patient has signed the informed consent form. Exclusion Criteria: Patients under 18 years of age. Patients who require a diathermic energy source (microwave, ultrasound or short wave). Patients with a pacemaker. Patients carrying a defibrillator. Patient with a cochlear implant. Patients with other active implanted devices. Patients who are scheduled to have any of the following procedures during the study period: an MRI, defibrillation or cardioversion, electrocautery, lithotripsy, radiofrequency or microwave ablation, and any other high-frequency ultrasound procedure, Women of childbearing age who do not use adequate contraception. Pregnant or breastfeeding. Participation in another trial. Patients who have expressed a desire not to participate in the study and have not formed informed consent. Patients with a failed spinal cord stimulation implant previously

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: Health Services Research
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Single-blind, multicenter, crossover
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: CME branch<br>In this study, the conventional spinal cord stimulation method (control Branch-CME branch) | Device: spinal cord stimulation conventional<br>* If the patient has been assigned to the branch of the CME control group, after mapping the search for the pain zone, the neurostimulator is programmed to conventional stimulation.<br>* Other names: CME;|
| Experimental: EME branch<br>In this study, the experimental spinal cord stimulation method are used in the same patient with the EVOLVE programming guide (EME branch) | Device: spinal cord stimulation experimental<br>* If the patient has been randomized to the branch of the EME experimental group, after a mapping of the search for the pain zone, a 90% subthreshold stimulation is programmed.<br>* Other names: EME;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparing Visual Analogue Scale (VAS) | Visual analogue scale (VAS) at the end of each test phase (either with conventional spinal cord stimulation or with EVOLVE). VAS consists of a 10 centimeter (cm) line, whose ends are defined as the extreme limits of pain (left end corresponds with the absence of pain and the right end with the maximum amount of pain). The patient is asked to point out in the line the place that better correspond to his/her pain, ranging from 0 to 10. | Baseline, After first stimulation (5days), after washout and second stimulation (12 days), After 30-day follow-up (42 days) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change (%) in VAS Scale at the End of Treatment. | Change (%) in Visual Analogue Scale (VAS) at the end of treatment. Δ = [(VAS Initial Visit - VAS Final Visit) / VAS initial visit] *100 Please note that positive values indicate a decrease in the VAS scale, which would indicate pain relief, as it was calculated as the value at the earlier time point minus the value at the later time point. | After first stimulation (Five days after baseline), After second stimulation (12 days after baseline), at the end of follow-up (42 days after baseline) | 
| Evaluation Disability | Oswestry Disability Index of the patients: it is a questionnaire consisting of 10 questions with 6 possible answers each. Every answer gives a punctuation from 0 (less disability) to 5 (more disability). This scale is expressed in percentage in which 0 percentage (%) would the least disability and 100 percentage (%) would represent the maximum disability. | Baseline, After first stimulation (+5 days), After washout and second stimulation (+12 days), at the end of follow-up (+42days) | 
| Number of Participants With Adverse Events in Each Arm | Considering as an adverse event those that result in death, or in severe harm to patient's health (lesion that threatens life, permanent harm on an organ or corporal function, or process that needs a medical or surgical intervention to avoid permanent harm) | 42 days from baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Spinal cord stimulation, Back surgery, Chronic pain