Fig 2. Computational domain.

The IVD is confined between two vertebral bodies, and due to axial symmetry, only the right upper quadrant of IVD is modeled. The computational domain comprehends 3 regions: NP (gray), AF (purple), and CEP (light blue). Along the lateral surface of the AF and at the CEP, the disc is in contact with the vascular network providing solutes (i.e., nutrients, growth factor, binding proteins and nicotine). Sketch dimensions are h _o = 5.5 mm, h ₁ = 0.6 mm, r _o = 15.5 mm, r ₁ = 4.3 mm, and r ₂ = 2.0 mm.