The pathophysiology of the intervertebral disc.

After a review of disk structure, the pivotal role of disk cells in producing and renewing the extracellular disk matrix is emphasized. Disk cells rely on nutrients that diffuse through the vertebral endplates. Microelectrode methods have been developed to study nutrient diffusion and endplate permeability. Mechanical stimuli modify disk cell activity. Scoliosis is associated with decreased endplate permeability, a factor that may play a role in disk degeneration and scoliosis progression.