Hu X, et al. - Researchers here aimed at determining the appropriateness of using the mid-sagittal magnetic resonance images (MRI) to measure various phenotypes of age-related disc degeneration. They observed that disc signal measurements acquired on the mid-sagittal MRI were reliable and had strong associations with age and thus can be used as an appropriate measure of disc degeneration. They suggested measuring disc bulging on para-sagittal MRIs as superior. Although severe disc narrowing clearly was a sign of severe disc degeneration, disc height seemed to have no linear association with age.