Assessing the potential anti-neuroinflammatory effect of minocycline in chronic low back pain: Protocol for a randomized, double-blind, placebo-controlled trial.

INTRODUCTION: Both preclinical studies, and more recent clinical imaging studies, suggest that glia-mediated neuroinflammation may be implicated in chronic pain, and therefore might be a potential treatment target. However, it is currently unknown whether modulating neuroinflammation effectively alleviates pain in humans. This trial tests the hypothesis that minocycline, an FDA-approved tetracycline antibiotic and effective glial cell inhibitor in animals, reduces neuroinflammation and may reduce pain symptoms in humans with chronic low back pain. METHODS AND ANALYSIS: This study is a randomized, double-blind, placebo-controlled clinical trial. Subjects, aged 18-75, with a confirmed diagnosis of chronic (≥ six months) low back pain (cLBP) and a self-reported pain rating of at least four out of ten (for at least half of the days during an average week) are enrolled via written, informed consent. Eligible subjects are randomized to receive a 14-day course of either active drug (minocycline) or placebo. Before and after treatment, subjects are scanned with integrated Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) using [11C]PBR28, a second-generation radiotracer for the 18 kDa translocator protein (TSPO), which is highly expressed in glial cells and thus a putative marker of neuroinflammation. Pain levels are evaluated via daily surveys, collected seven days prior to the start of medication, and throughout the 14 days of treatment. General linear models will be used to assess pain levels and determine the treatment effect on brain (and spinal cord) TSPO signal. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT03106740).

An evaluation of MRI lumbar spine scans within a community-based diagnostic setting.

BACKGROUND: With an ongoing move towards more management of patients within the community setting, demand for magnetic resonance imaging (MRI) is increasing and commonly used in lower back conditions. There is well recorded overuse of MRI in this scenario which goes against evidence-based practice and adds to rising healthcare costs. METHODS: The study was a retrospective review of lumbar spine MRI scans performed within a community-based setting over an 18-month period. The review took a randomised purposive sample of patients (n = 450); looking at adherence to, and relevance of, guidelines in managing lower back conditions. Data extracted provided information on demographics and prevalence of clinical presentation and report observations. RESULTS: There is variation in practice and utlisation of MRI with this patient group which warrants further exploration. Results support inappropriate use, lacking adherence to guidelines and pathways, leading to unnecessary imaging. 46% of referrals were considered clinically justified with 38% of report findings considered abnormal and of clinical relevance. Chi-square and binomial logistic regression were used to assess the significance and relationship of any factors on referral justification and report outcome. No difference was found between type of referrer, with patient age and leg symptoms being significant factors. CONCLUSION: The study highlights the opportunity to integrate better referral criteria to improve referral quality, its suitability and the relevance of final reports. In the current climate this would help manage appropriate use of imaging resources during the post COVID-19 pandemic recovery phase, as well as support recommendations regarding diagnostic reform and a move towards more community-based diagnostics.