FDG PET/MRI Evaluation of Facet Joint Pain
Condition: Low Back Pain
MeSH terms: Arthralgia; Low Back Pain
Study type: Interventional

Summary: 
      Chronic pain incurs over half a trillion dollars in lost productivity (healthcare, lost
      wages, etc) annually. The most common source is low back pain (LBP), often from facet joints.
      The clinical evaluation of facet joints is challenging and anatomic imaging findings of facet
      joint; degenerative change; correlate poorly with pain. Therefore, it is difficult to select
      appropriate candidate patients/facet joints to treat. Misguided percutaneous treatment can
      cost thousands of dollars per session and delay diagnoses. Very limited retrospective
      information suggests that high grade peri-facet MRI signal change correlates to the side of
      LBP. However, this has not fully characterized the imaging findings and has not correlated to
      expert clinical exam/percutaneous response, precluding robust and meaningful clinical impact.
      Minimal retrospective data concludes inflammatory changes can be identified on FDG-PET exams,
      but the evidence of correlation to patient pain is lacking. Limited DWI exists for
      inflammatory spondyloarthropathies and myopathies, but is also lacking.

      This is an exploratory study investigating the utility of FDG PET activity and MRI signal
      change around facet joints in the clinical management of low back pain. This study will help
      determine if such imaging biomarkers could change clinical management. Additionally, this
      will provide data that will be vital to planning a larger prospective study evaluating the
      ability of imaging biomarkers to predict response to comparison medial branch blocks and RF
      ablation for treatment of facet joint pain.
    

Detailed description: 
      10 patients with a clinical suspicion of at least 60% likelihood that low back pain arises
      from the lumbar facet joints will be recruited in clinic. The clinicians will rate the
      likelihood clinically of facet joint origin of pain and will assign a theoretical treatment
      plan based on initial clinical impression. They will indicate which facet joints, if any,
      they would refer for percutaneous treatment. The patients will undergo and FDG PET/MRI of the
      lumbar spine with IV gadolinium. The MRI signal change and enhancement of the lumbar facet
      joints will be graded by 2 radiologists blinded to the clinical data. The FDG PET scan
      activity of the facet joints will be graded by two nuclear medicine radiologists blinded to
      the clinical information. The clinicians will then be segmentally unblended to the imaging
      data as follows: 1. facet joints with high grade MRI signal change, 2. facet joints with any
      MRI signal change, 3. facet joints with high grade PET activity, and 4. facet joints with any
      PET activity. At each of these 4 steps, the clinician will indicate if this information would
      have the potential to alter clinical care (assuming that the imaging biomarker in question
      would be a surrogate for inflammation and pain) and if the information is concordant to the
      clinical impression. The clinical course of each patients will be followed for 1 year after
      undergoing the PET/MRI examination.
    

Intervention name(s): FDG PET/MR examination.
Intervention type(s): Device
Intervention description(s): All recruited patients will undergo an FDG PET examination focused on the lumbar spine.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic