Comparison of Dorsal Column Stimulation to Dorsal Root Ganglion Stimulation for Complex Regional Pain Syndrome

Study Overview
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Brief Summary
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Complex Regional Pain Syndrome (CRPS) is a constellation of pain symptoms which are associated with impairment in mood, social and physical function. Spinal Cord Stimulation (SCS), a technique of placing electrodes into the epidural space is a validated treatment for Complex Regional Pain Syndrome . Treatment of CRPS with SCS, in combination with physical therapy, reduced pain to a greater degree than physical therapy alone. 40%-50% of CRPS patients achieve >50% pain relief with SCS using dorsal column stimulation . Dorsal Root Ganglion (DRG) SCS has also recently demonstrated clinical efficacy in patients with CRPS and peripheral causalgia . The hypothesis is that DRG stimulation is non-inferior to dorsal column SCS in patients with CRPS who have failed to respond to a course of analgesics and physical therapy. The aim to assess functional, quality of life, patient satisfaction and medication requirements in subjects treated with neuromodulation for CRPS and contrast outcomes amongst subjects treated with DRG SCS and dorsal column SCS.

Detailed Description
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The purpose of this study is to compare outcomes between dorsal column spinal cord stimulation and dorsal root ganglion spinal cord stimulation in patients with Complex Regional Pain Syndrome at an infraumbilical location who have failed a course of conservative management including analgesic pharmacotherapy and physical therapy. This is a prospective randomized post-marketing clinical study. Patients will be randomized in a 1:1 ratio to Dorsal Column or Dorsal Root Ganglion Spinal Cord Stimulation if they have failed a course of conservative management including analgesics and physical therapy. All patients are expected to undergo clinical, neurological, and imaging assessments, if appropriate, at selected follow-up visits. The study will be conducted a single center with a target maximum of 62 patients (31 randomized to each group). Enrollment of subjects in this study is anticipated to take 24 months. Clinical follow-up evaluations will be conducted at 10 days, 1, 3 and 6 months post-implant. The total study duration is expected to be at least 30 months. All patients presenting to the Investigators with Budapest criteria, research subset , for the diagnosis of Complex Regional Pain Syndrome at an infraumbilical location who have not had an adequate response to a course of conservative management including analgesics and physical therapy will be screened for eligibility. A Screening/Enrollment Log will be utilized in order to maintain a cumulative tracking of all screened patients. Patients must meet all inclusion/exclusion criteria for enrollment in the clinical study. Reasons for screening failure(s) will be documented.

Official Title
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Single Center, Randomized Prospective Comparative Effectiveness Study of Dorsal Column Spinal Cord Stimulation to Dorsal Root Ganglion Stimulation in the Treatment of Complex Regional Pain Syndrome

Conditions
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Complex Regional Pain Syndrome

Intervention / Treatment
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* Device: The Nuvectra Algovita Dorsal Column Spinal Cord Stimulator
* Device: The Axium Neurostimulator System


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Patient is greater than18 years of age An infraumbilical location of the index pain Symptoms have been present for greater than 6 months Continuing pain which is disproportionate to any inciting event Report hyperesthesia and/or allodynia Report vasomotor changes including temperature asymmetry and/or skin color changes and/or skin color asymmetry Report edema and/or sweating changes and/or sweating asymmetry Report decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin) Display at least one sign in two or more of the following categories: Sensory: Evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or temperature sensation and/or deep somatic pressure and/or joint movement) Vasomotor: Evidence of temperature asymmetry (>1°C) and/or skin color changes and/or asymmetry Sudomotor/Edema: Evidence of edema and/or sweating changes and/or sweating asymmetry Motor/Trophic: Evidence of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin) Patient failed to have resolution of symptoms despite at least 4 weeks of conservative management including analgesic pharmacotherapy and physical therapy Patient has index site pain > spine pain The subject is physically and mentally able to participate in the study Patient is willing and able to provide informed consent Patient is willing and able to comply with the study protocol Exclusion Criteria: Previous surgery to the spine which could compromise placement of the study device Anatomical spinal abnormality including severe central canal stenosis or bony foraminal impingement which could preclude device placement Foreseen need for MRI to monitor or evaluate another chronic condition Previous experience with an implanted or trial neuromodulation system (spinal cord stimulation, peripheral nerve stimulation) for the treatment of pain at the index location Active local or systemic infection Actively in litigation for pain symptoms Currently on Workman's Compensation Women who are pregnant or intend to become pregnant during the study duration

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Dorsal Column Stimulation<br>Subjects with Complex Regional Pain Syndrome receiving implant with the Nuvectra Algovita Dorsal Column Spinal Cord Stimulator | Device: The Nuvectra Algovita Dorsal Column Spinal Cord Stimulator<br>* The Nuvectra Algovita Dorsal Column Spinal Cord Stimulator is indicated as an aid in the management of chronic intractable pain of the trunk and/or limbs, including unilateral or bilateral pain associated with failed back surgery syndrome, intractable low back pain and leg pain.<br>|
| Dorsal Root Ganglion Stimulation<br>Subjects with Complex Regional Pain Syndrome receiving implant with the Axium Neurostimulator System | Device: The Axium Neurostimulator System<br>* The Axium Neurostimulator System is indicated for spinal column stimulation via epidural and intra-spinal lead access to the dorsal root ganglion as an aid in the management of moderate to severe chronic intractable pain of the lower limbs in adult patients with Complex Regional Pain Syndrome Types I and II<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Numerical Rating Scale for Pain Intensity | To compare the outcomes of dorsal column stimulation with Dorsal Root Ganglion stimulation in patients with Complex Regional Pain Syndrome that persist despite a course of conservative management including physical therapy and analgesic pharmacotherapy using an 11-point [0-10] Numerical Rating Scale (NRS) for Pain Intensity at 6 months. A score of zero indicates no pain, and 10 indicates the worst possible pain imaginable. | 6 Months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Oswestry Disability Index for Pain Intensity | To compare the outcomes of dorsal column stimulation with Dorsal Root Ganglion stimulation in patients with Complex Regional Pain Syndrome that persist despite a course of conservative management including physical therapy and analgesic pharmacotherapy in function based on Oswestry Disability Index (ODI) for functional impairment. A score of 0 on the 101-point [0-100] Oswestry Disability Index indicates no disability while 100 indicates bed-bound. | 6 Month |