Fig. 1From: Differences in calcification and osteogenic potential of herniated discs according to the severity of degeneration based on Pfirrmann grade: a cross-sectional studyμ-CT scan revealing that the posterior portions of the removed intervertebral discs contained more ossification sites than the anterior portions. White spots indicate the calcification spots in the removed disc. a is a Pfirrmann grade III disc, and (b) is a Pfirrmann grade V discBack to article page