Age and Disc Degeneration in Low Back Pain: Automated Analysis Enables a Magnetic Resonance Imaging Comparison of Large Cross-Sectional Groups of Symptomatic and Asymptomatic Subjects

Background: Degeneration of the intervertebral disc has long been associated with low back pain even though disc degeneration is seen in people who are asymptomatic. Investigations into the relationship between pain and disc degeneration in symptomatic and asymptomatic subjects are hampered by study sizes, by variations in definition of back pain and differences in MRI annotations of degeneration, study-to-study. Methods: We compared prevalence of disc degeneration between large symptomatic (724) and asymptomatic (701) groups of anonymised female subjects, 30-80yrs. We used SpineNet, a verified automated MRI annotation system to re-annotate MRIs onto the same objective system, irrespective of their original annotation. SpineNet rapidly annotated all MRIs for disc degeneration using the Pfirrmann scale 1-5, and for other degenerative features (herniation, endplate defects, marrow signs, spinal stenosis) as binary present/absent, taking age and spinal level into account. Findings: Severe disc degeneration (Pfirrmann 4 or 5) and degenerative features were significantly more prevalent in symptomatics than in asymptomatics in the lower (L4-S1) but not the upper (L1-L3) lumbar discs, and in subjects