Spinal Cord Stimulation With Precision® System Versus Reoperation for Failed Back Surgery Syndrome

Spinal Cord Stimulation With Precision® Spinal Cord Stimulation System Versus Reoperation for Failed Back Surgery Syndrome

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.

The co-primary study endpoints are proportion of subjects with ≥50% leg pain relief without crossover at 6 and at 24 months.

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