Fig. 4

Evaluation of IDD therapy of PCL, PCL/2% celecoxib, and PCL/6% celecoxib nano fibers in vivo. a, b IDD rabbit puncture model and the therapy with nano fibers. c MRI of rabbit intervertebral discs treated with PCL, PCL/2% celecoxib, and PCL/6% celecoxib nano fibers. Blue arrow indicating loss of hydration and the red arrow indicating recovery of hydration. e HE staining, and f SOFG staining of rabbit intervertebral disc treated with PCL, PCL/2% celecoxib, and PCL/6% celecoxib nano fibers. d High signal ratio in the disc of MRI. g Degeneration score of HE. h–i Biomechanical properties of the intervertebral disc. j Celecoxib concentrations in the intervertebral disc. *P < 0.05 compared with the puncture group, ^#P < 0.05 compared with the puncture + PCL celecoxib group, and ^†P < 0.05 compared with the puncture + PCL/2% celecoxib group