Cryoneurolysis vs Radiofrequency Ablation for Chronic Sacroiliac Joint Pain

This is a single-center, randomized, pilot study in adult subjects with chronic SIJ pain. Thirty (30) subjects are planned for initial enrollment and will be randomized 1:1 to receive ioveraº cryoneurolysis or radiofrequency ablation (RFA).

This study is designed to evaluate the clinical effectiveness of iovera° cryoneurolysis in adult subjects with chronic SIJ pain. Furthermore, the study will assess the feasibility of the outcome measurements employed, construct a foundation for sample size calculation, and the acceptability/practicality of conducting an efficacy randomized controlled trial (RCT).

Randomization to treatment groups according to the randomization assignment will be performed on the day of treatment.

Inclusion criteria

• Subjects at least 18 years of age at Screening
• Primary complaint of buttock or axial low-back below L5 suggestive of unilateral or bilateral SIJ-mediated back pain
• Positive SIJ provocative testing (at least two tests must be positive)

• Thigh thrust test
• Distraction test
• Gaenslen's test
• Compression test
• Sacral thrust test
• Low back or buttock pain is chronic (i.e., ≥ 3 months' duration)
• Low back or buttock pain is moderate to severe (score of ≥ 4 to ≤ 9) on the 0 to 10 NRS at Screening
• Low back or buttock pain causes functional impairment (≥ 30% on ODI) at Screening
• Successful trial of one diagnostic sacroiliac joint block with local anesthetic and steroids that results in at least 50% relief of primary (index) pain for the duration of the local anesthetic used
• Failure of at least three months of conservative non-operative therapy (e.g., physical therapy, chiropractic care, sleep hygiene, weight loss, spinal injections, NSAIDs, physician-directed exercise program or other appropriate analgesics)
• Able to provide informed consent, adhere to the study visit schedule, and complete all study assessment

Exclusion criteria

• Active workers' compensation, personal injury, Social Security disability insurance (SSDI), or other litigation/compensation related to the spine
• Serious spinal disorders (verified on magnetic resonance imaging (MRI)) that may impact outcomes, including any of the following:

• Suspected cauda equina syndrome (e.g., bowel/bladder dysfunction)
• Infection
• Tumor
• Traumatic fracture
• Systemic inflammatory spondyloarthropathy
• Lumbar radiculopathy/radiculitis (i.e., root irritation and deficit)
• Neurogenic claudication
• Prior SIJ fusion surgery across the SI joint
• Comorbidity that, in the judgment of the Investigator, may affect the subject's ability to participate in the study including lumbar radiculopathy and neuropathic pain disorder
• Currently pregnant, nursing, or planning to become pregnant during the study
• Known contraindication to study device, including any of the following:

• Cryoglobulinemia
• Paroxysmal cold hemoglobinuria
• Cold urticaria
• Raynaud's disease
• Open and/or infected wounds at or near the treatment site
• Coagulopathy
• Previous participation in an iovera° study
• Severe chronic pain disorder that in the opinion of the investigator may impact study outcomes
• Presence of any of the following:

• Spinal neurostimulator
• Intrathecal analgesic drug pump
• Current manifestation of poorly controlled mental illness or catastrophizing that in the opinion of the investigator may meaningfully impact treatment outcomes, including any of the following:

a. Mood disorder (e.g., depression, bipolar) i. Patient Health Questionnaire (PHQ-9) ≥ 12 at Screening b. Psychotic disorder (e.g., schizophrenia) c. Catastrophizing i. Pain Catastrophizing Scale (PCS) score >30 at Screening

• Subject received other spine interventions/therapies in the 30 days prior to block administration (e.g., spinal injections, minimally invasive therapies, surgical therapies) at the intended lumbar treatment levels
• Subject received radiofrequency ablation ≤ 6 months before study enrollment at the intended treatment levels
• History, suspicion, or clinical manifestation of:

• Alcohol abuse or dependence
• Illicit drug use
• Opioid abuse or dependence (≥40 mg MED PO/day in past 30 days) Given the COVID-19 pandemic, the subject must be medically fit/cleared for surgery by the investigator. If there is a concern about a subject's recent or potential exposure to COVID-19, or if the subject is not medically fit/cleared for surgery due to suspected COVID-19 illness/symptoms (or other serious illness), the subject must be excluded per Exclusion criterion #4.