A Safety and Effectiveness Trial of Spinal Cord Stimulation of the Dorsal Root Ganglion for Chronic Lower Limb Pain

Not Applicable

Completed

Conditions: Chronic Lower Limb Pain

Interventions: Device: AXIUM Neurostimulator System
Device: Control Spinal Cord Stimulation Device

Registration Number: NCT01923285

Lead Sponsor: Abbott Medical Devices

Brief Summary: The purpose of this study is to evaluate the safety and effectiveness of the AXIUM Neurostimulator System for the treatment of chronic lower limb pain in persons diagnosed with Complex Regional Pain Syndrome (CRPS) or Peripheral Causalgia (PC).

Detailed Description: The ACCURATE study is a prospective, randomized, controlled, multicenter clinical trial designed to assess the safety and efficacy of the Spinal Modulation Axium Neurostimulator System as an aid in the management of chronic, intractable pain of the lower limbs, including unilateral or bilateral pain associated with one of the following conditions: Complex Regional Pain Syndrome (CRPS) or Peripheral Causalgia (also referred to as CRPS Type II).

Enrolled subjects were diagnoses with CRPS or peripheral causalgia; experienced pain for at least six months; and failed to achieve adequate pain relief from at least two prior pharmacologic treatments.

All subjects had a temporary trial neurostimulator (TNS). If the subject was a treatment success at the end of TNS they were scheduled for the fully implantable neurostimulator (INS) implant procedure. If not, subjects were exited from the study.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 152

Inclusion Criteria

Subject is male or female between the ages of 22 and 75 years
Subject is able and willing to comply with the follow-up schedule and protocol
Subject has chronic, intractable pain of the lower limb(s) for at least 6 months
Subjects are diagnosed with complex regional pain syndrome (CRPS) and/or peripheral causalgia
Subjects have a minimum Visual Analog Scale (VAS) greater than or equal to 60 mm in the area of greatest pain in the lower limbs.
Subject has failed to achieve adequate pain relief from at least 2 prior pharmacologic treatments from at least 2 different drugs classes
Subject has had stable neurologic function in the past 30 days
In the opinion of the Investigator, the subject is psychologically appropriate for the implantation of an active implantable medical device
Subject is able to provide written informed consent

Exclusion Criteria

Back pain is the greatest region of pain as measured on the baseline VAS.
Female subject of childbearing potential is pregnant/nursing, plans to become pregnant or is unwilling to use approved birth control
Subject has exhibited escalating or changing pain condition within the past 30 days as evidenced by Investigator examination
Subject is currently involved in medically related litigation, including workers compensation
Subject has had corticosteroid therapy at an intended site of stimulation within the past 30 days
Subject's pain medication(s) dosage(s) are not stable for at least 30 days
Subject has had radiofrequency treatment of an intended target Dorsal Root Ganglion within the past 3 months
Subject has previously failed spinal cord stimulation therapy
Subject currently has an active implantable device including implantable cardioverter defibrillator, pacemaker, spinal cord stimulator or intrathecal drug pump or subject requires magnetic resonance imaging (MRIs) or diathermy
Subject has pain only within a cervical distribution
Subject has cognitive, physical or sensory impairment that, in the opinion of the Investigator, may limit their ability to operate the device
Subject currently has an indwelling device that may pose an increased risk of infection
Subject currently has an active systemic infection.
Subject has, in the opinion of the investigator, a medical comorbidity that contraindicates placement of an active medical device
Subject has participated in another clinical investigation within 30 days
Subject has a coagulation disorder or uses anticoagulants that, in the opinion of the Investigator, precludes participation
Subject has been diagnosed with cancer in the past 2 years
Imaging (MRI, CT, x-ray) findings within the last 12 months that, in the Investigator's opinion, contraindicates lead placement
Subject is a prisoner

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
AXIUM Neurostimulator System	AXIUM Neurostimulator System	The AXIUM Neurostimulator System is an investigational spinal cord stimulation device that is designed to stimulate the dorsal root ganglion (DRG) of the spine located on the back surface of the spinal cord where nerves exit the backbone. The device has 2 parts that are placed surgically (implanted) : 1) a pulse generator which is placed under the skin in the buttocks or abdomen, and 2) up to four wires (leads) that have one end attached to the pulse generator, and the other end secured to the tissue near the target treatment area.
Control Spinal Cord Stimulation Device	Control Spinal Cord Stimulation Device	The Control Spinal Cord Stimulation Device is a commercially available spinal cord stimulator indicated for the treatment of chronic lower limb pain.

Primary Outcome Measures

Name	Time	Method
Primary Composite Endpoint - Treatment Success	3 months	Treatment Success is defined as at least 50% lower limb pain relief (VAS score reduction) at the end of trial phase, received at least 50% lower limb pain relief at the 3-month visit post implant, and the absence of a stimulation related neurological deficit. Pain scores were measured using Visual Analog Scale (VAS). The VAS score ranges from 0-100 mm with a higher score indicating higher pain intensity ( 0 representing "No Pain" and 100 mm representing "Worst Imaginable Pain").

Secondary Outcome Measures

Name	Time	Method
Positional Effects on Paresthesia Intensities	3 months	Positional effects on paresthesia intensities at 3 months in the Control group versus the Treatment Group. This endpoint will compare the difference in paresthesia scores upright and supine between the AXIUM and Control groups. Paresthesia intensity was rated by subjects using a paresthesia intensity rating scale. Subjects rated the intensity of their perception of paresthesia, while upright and supine, on an 11-point numeric rating scale from 0 representing "No feeling" to 10 "Very intense." Perceived paresthesia intensity difference between supine and upright positions was calculated and averaged across each group.

Trial Locations

Locations (22): Florida Pain Institute
🇺🇸
Merritt Island, Florida, United States
Premier Pain Center
🇺🇸
Shrewsbury, New Jersey, United States
Southeastern Spine Institute
🇺🇸
Mount Pleasant, South Carolina, United States
Newport Beach Headache and Pain
🇺🇸
Newport Beach, California, United States
Eisenhower Medical Center
🇺🇸
Rancho Mirage, California, United States
Drug Studies of America
🇺🇸
Marietta, Georgia, United States
IPM Medical Group, Inc.
🇺🇸
Walnut Creek, California, United States
Orthopaedic Pain Specialists
🇺🇸
Santa Monica, California, United States
Pain Clinic of Monterey Bay
🇺🇸
Aptos, California, United States
Comprehensive Pain and Rehabilitation
🇺🇸
Pascagoula, Mississippi, United States
Holy Cross Hospital Orthopedic Institute
🇺🇸
Oakland Park, Florida, United States
HOPE Research - LVSP
🇺🇸
Las Vegas, Nevada, United States
The Center for Clinical Research
🇺🇸
Winston-Salem, North Carolina, United States
Clinical Trials of South Carolina
🇺🇸
Charleston, South Carolina, United States
Cleveland Clinic Foundation
🇺🇸
Cleveland, Ohio, United States
Pain Management Associates
🇺🇸
Independence, Missouri, United States
Center for Pain Relief
🇺🇸
Charleston, West Virginia, United States
Center for Pain Relief Tri-State
🇺🇸
Huntington, West Virginia, United States
HOPE Research - TPC
🇺🇸
Phoenix, Arizona, United States
Coastal Pain Research
🇺🇸
Carlsbad, California, United States
Neurovations, Inc.
🇺🇸
Napa, California, United States
Houston Pain Centers
🇺🇸
Houston, Texas, United States