Biomarkers in the Degenerative Human Intervertebral Disc Tissue and Blood

Patients with back pain comprise a large proportion of the outpatient practice among physiatrists. Diagnostic tools are limited to clinical history, physical examinations and imaging. Non-surgical treatments are largely empirical, encompassing medications, physical therapy, manual treatments and interventional spinal procedures. A body of literature is emerging confirming elevated levels of biomarkers including inflammatory cytokines in patients with back pain and/or radiculopathy, largely because the protein assay sensitivity has increased. These biomarkers may serve as tool to assist diagnosis and assess outcomes. The presence of inflammatory mediators in the intervertebral disc tissues and blood helped confirming the inflammatory underpinnings of back pain related to intervertebral disc degeneration. Literature reviewed here suggests that biomarkers could assist clinical diagnosis and monitor physiological outcomes during and following treatments for spine related pain. Biomarkers must be measured in a large and diverse asymptomatic population, in the context of age and comorbidities to prevent false positive tests. These levels can then be rationally compared to those in patients with back disorders including discogenic back pain, radiculopathy and spinal stenosis. While studies reviewed here used “candidate marker” approaches, future non-biased approaches in clearly defined patient populations could uncover novel biomarkers in clinical management of patients.