The relationship between cartilage end-plate calcification and disc degenerat ion: an experimental study

Objective To study the relationship between cartilage end-plate calcification and interve rtebral disc degeneration. Methods An experimental model of cervical disc degeneration in rabbits was established b y resection of the cervical supraspinous and interspinous ligaments and detachme nt of the posterior paravertebral muscles from the cervical vertebrae.Mechanic al instability in the cervical spine elicited by this surgical intervention acce lerated the process of intervertebral disc degeneration.The extent of interver tebral disc degeneration was graded in morphologically, and the thicknesses of t he calcified layer and the uncalcified layer of the cartilage end-plate were me asured in each degenerated cervical disc. Results In less severely degenerative cervical discs, the morphology of the cartilage en d-plate showed nearly normal construction, and the tidemark was clear.In seve rely degenerative discs, the matrix and cells showed fibrosis, the tidemark adva nced, and the calcified cartilage thickened.There exists a positive correlatio n between the thickness of the calcified layer of the cartilage end-plate and t he degree of cervical disc degeneration. Conclusion The calcification of the cartilage end-plate is the key factor that initiates a nd promotes cervical disc degeneration.