Safety and Efficacy of the TransDiscal System Versus Medical Management in Treating Chronic Discogenic Low Back Pain

The intervertebral discs serve as joints between the vertebral bodies, providing both structural support and flexibility to the spinal column. Intervertebral discs do not remain structurally intact over a lifetime and degenerate as a natural part of aging. Degenerated discs do not react to stresses and forces the same as healthy discs. When too much stress is applied to a degenerated disc, tears can result. Evidence suggests that when a tear is present, sensory nerve endings can grow into the tear and transmit pain.

The TransDiscal System (TDS) is a medical device that is used in a procedure called Disc Biacuplasty and is currently available in the United States and throughout the world. The TDS enables the back of the disc to be heated to high enough temperatures to ablate the nerves inside that are transmitting pain, while maintaining low enough temperatures to prevent damage to surrounding tissues. The TDS uses two electrodes, located at the ends of two thin probes, which are placed on both sides of the back of the intervertebral disc by inserting them through the skin into the disc using x-ray guidance. Radiofrequency (RF) current flows in the disc between the two electrodes, heating the tissue in the disc to the desired temperature. The study evaluates a modified heating protocol than what is currently in clinical use which should allow for a larger area of the back of the disc to be heated.

Inclusion criteria

• Age ≥21 years
• Able to understand the informed consent and able to complete outcome measures
• Objective measurements indicating functional impairment related to low back pain
• Stabilized on pain medication regimen for >2 months as defined by a <10% change in dosage
• History of chronic low back pain (>6 months) unresponsive to non-operative care (including physical therapy, anti-inflammatory medication, epidurals, diagnostic facet joint/medial branch blocks, and sacroiliac joint interventions as performed or deemed appropriate by the Investigator)
• Score ≥5 on the Visual Analog Scale (VAS) relating specifically to the average daily low back pain
• Back pain more prominent than leg pain which is commonly exacerbated by flexion or bending or prolonged sitting.
• Single level concordant pain reproduction present on lumbar discography in desiccated disc. Magnetic resonance Imaging (MRI) image also supports discography findings. Changes in other disc spaces in the lumbar region do not demonstrate neural compressive lesion.
• Disc height at least 50% of adjacent control disc

Exclusion criteria

• Evidence of compressive radiculopathy with predominant leg pain
• Evidence of nucleus pulposus herniation or free disc fragments on MRI
• Evidence of > 2 discs dessicated based on MRI or symptomatic involvement of more than one lumbar disc levels.
• Asymptomatic disc bulges > 5 mm at the treatment level.
• Prior lumbar surgery of any kind at the treatment level (micro-discectomies, and/or minimally invasive procedures at other levels that are not excluded)
• Prior spinal fusion below the T10 Level
• Symptoms or signs of lumbar canal stenosis at any level
• Evidence of structural abnormality at the lumbar level (except non-symptomatic spondylolysis resulting in spondylolithesis no more than Grade 1 upon flexion and extension)
• Any generalized pain or multifocal pain,conversion or multiple non-anatomical complaints
• Pending or active compensation claim, litigation or disability income remuneration (secondary gain)
• Chronic pain associated with significant psychosocial dysfunction
• Beck's Depression Index (BDI) score >20
• Current pregnancy, recent delivery (within 3 months of consent) or the intent of becoming pregnant during the study period.
• Systemic or localized infection at the anticipated needle entry site (subject may be considered for inclusion once infection is resolved)
• Discitis
• Allergies to any medication to be used in the procedure
• Present symptomatic lumbar spinal fracture
• History of uncontrolled coagulopathy, ongoing coagulation treatment or unexplained or uncontrollable bleeding that is uncorrectable
• Progressive neurological deficits
• Within the preceding 2 years, subject has suffered from active narcotic addiction, substance abuse or alcohol abuse
• Current prescribed opioid medications equivalent to >120 mg of morphine per 24 hours
• Uncontrolled immunosuppression (e.g. Acquired Immune Deficiency Syndrome [AIDS], cancer, diabetes, etc.)
• Body Mass Index (BMI) >32.5 kg/m^2
• Participating in another clinical trial/investigation 30 days prior to signing informed consent
• Negative or indeterminate lumbar discography results as assessed per International Spine Intervention Society (ISIS) guidelines
• Subject unwilling or unable to comply with follow up schedule or protocol requirements.