Fig. 4

Change in percent disc height index (%DHI). Disc height (DH) was measured every 2 weeks by radiography in rabbit discs injected with the designated dose of monosodium iodoacetate (MIA) in contrast agent (CA) (L2–L3 MIA 0.01 mg, L3–L4 MIA 0.1 mg, and L4–L5 MIA 1.0 mg) and converted to percentage of disc height (%DHI). The mean %DHI of the discs decreased time-dependently (P < 0.01) and was significantly lower compared to that of the CA control (L1–L2) (P < 0.01, respectively). Data are expressed as mean ± standard error of the mean (SEM). Two-way analysis of variance and post hoc Bonferroni multiple comparisons test were used to compare all groups. **P < 0.01