Back Pain, Failed Back Surgery Syndrome, Pain
Conditions
Keywords
Spinal Cord Stimulation, Decompression, Fusion with or without instrumentation, Discectomy, Laminectomy, Laminotomy, Foraminotomy
Brief summary
The EVIDENCE trial is a randomized controlled trial comparing the therapeutic effectiveness and cost-effectiveness of the Precision® Spinal Cord Stimulation with that of reoperation as a treatment of pain in patients with Failed Back Surgery Syndrome (FBSS). FBSS is defined as persistent or recurrent pain following one or more lumbosacral spine surgical procedures. Surgical procedures that can result in FBSS can be categorized as either decompression or decompression followed by fusion with or without instrumentation. The pain of FBSS is categorized as neuropathic, which involves pathological nerve activity and is commonly characterized by patients as shooting or burning and/or nociceptive, which signals actual or impending tissue damage or inflammation.
Detailed description
The co-primary study endpoints are proportion of subjects with ≥50% leg pain relief without crossover at 6 and at 24 months.
Interventions
DEVICEPrecision Spinal Cord Stimulator
Programming settings will be specific to the individual needs in accordance with the labeling
PROCEDUREBack Surgery
Different types of back surgery may be performed
Sponsors
Boston Scientific Corporation
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Primary pain type - neuropathic with concordant radicular or neurological findings * Significant complaint of persistent or recurrent radicular leg pain, with or without low back pain * One or more prior lumbosacral surgical procedures (no upper limit) * At least 6 months duration of persistent or recurrent radicular leg pain, with or without low back pain * Study candidates meet the criteria for a specific surgical intervention as recorded by a surgeon: pain refractory to conservative care, with concordant neurologic, tension, and/or mechanical signs and imaging findings of surgically remediable neural compression * MRI or CT myelogram of the lumbar and thoracic spine (within 12 months prior to screening) that rules out pathology that might compromise SCS electrode placement or pathology, in addition to neural compression, that might contribute to the subject's pain * All study candidates must pass study site's routine psychological/psychiatric evaluation for SCS before randomization to SCS or reoperation * At least 18 years of age * Subject signs informed consent
Exclusion criteria
* Chief complaint of mechanical low back pain (e.g. pain that a recumbent position relieves completely) * Pain intensity of always 10 on a 0-10 Numerical Rating Scale over the past 6 months based on subject recall * Radiographic evidence of frank instability (grossly mobile spondylolisthesis or abnormal subluxation) requiring fusion, calcific arachnoiditis, or severe thoracic stenosis * Radiographically demonstrated (by myelographic block or its MRI equivalent) critical cauda equinal compression * A disabling or potentially disabling neurologic deficit (e.g., foot drop, neurogenic bladder) in the distribution of a nerve root or roots caused by surgically remediable compression * A predominance of non-organic signs on physical exam * A concurrent clinically significant or disabling chronic pain problem or condition that is likely to confound evaluation of study endpoints (e.g., chronic migraine, significant arthrosis of the hip associated with groin pain as primary complaint) * Significant substance abuse issues * Major untreated psychiatric comorbidity * Unresolved issues of secondary gain (e.g., litigation) * Expected inability to report treatment outcome adequately * Expected inability to operate SCS system * Pregnancy (actual or planned) * Life expectancy less than 3 years due to other serious medical condition(s) * Active local or systemic infection * Prior SCS procedure * Presence of intrathecal drug pump * Participation in another clinical study that would confound data of this study * Occupational risk that would rule out SCS * Medical or cardiac condition(s) or therapies, or foreseeable need for therapies or diagnostic tests (e.g., MRI), that preclude SCS and/or reoperation
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 3, 6- and 12- months post-index procedure |
Countries
Canada, France, United Kingdom, United States
Participant flow
Recruitment details
Subjects were recruited for participation from February 2010 to June 2012.
Pre-assignment details
A total of 274 subjects were screened for participation.After screening, 75 subjects were eligible for participation. Of the eligible subjects, 47 declined randomization. A total of 28 subjects were randomized.
Participants by arm
| Arm | Count |
|---|---|
| Precision Spinal Cord Stimulator Precision Spinal Cord Stimulation System | 11 |
| Back Surgery Discectomy, laminotomy, laminectomy, foraminotomy, fusion with or without instrumentation | 14 |
| Total | 25 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 0 | 1 |
| Overall Study | Lost to Follow-up | 0 | 1 |
| Overall Study | Physician Decision | 1 | 0 |
| Overall Study | Sponsor study termination | 11 | 12 |
| Overall Study | Withdrawal by Subject | 1 | 1 |
Baseline characteristics
| Characteristic | Back Surgery | Total | Precision Spinal Cord Stimulator |
|---|---|---|---|
| Age, Continuous | 57 years STANDARD_DEVIATION 15.3 | 54.9 years STANDARD_DEVIATION 13.9 | 52.3 years STANDARD_DEVIATION 12 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 2 Participants | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 4 Participants | 3 Participants |
| Race (NIH/OMB) White | 12 Participants | 19 Participants | 7 Participants |
| Sex: Female, Male Female | 4 Participants | 11 Participants | 7 Participants |
| Sex: Female, Male Male | 10 Participants | 14 Participants | 4 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 3 / 13 | 2 / 15 |
| serious Total, serious adverse events | 1 / 13 | 4 / 15 |
Outcome results
Primary
Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment
Time frame: 3, 6- and 12- months post-index procedure
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Precision Spinal Cord Stimulator | Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 3 Month (7 subject Stimulation, 9 Subjects Surger) | 0.86 proportion of participants |
| Precision Spinal Cord Stimulator | Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 6 Month (6 subjects for Stimulation and Surgery) | 0.5 proportion of participants |
| Precision Spinal Cord Stimulator | Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 12 month (4 subjects for Stim, 3 subjects Surgery) | 1.0 proportion of participants |
| Back Surgery | Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 3 Month (7 subject Stimulation, 9 Subjects Surger) | 0.44 proportion of participants |
| Back Surgery | Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 6 Month (6 subjects for Stimulation and Surgery) | 0.5 proportion of participants |
| Back Surgery | Proportion of Subjects Showing ≥50% Self-reported Leg Pain Relief From Baseline Without Request for Crossover to the Other Treatment | 12 month (4 subjects for Stim, 3 subjects Surgery) | 0.33 proportion of participants |