Ontogenesis of human intervertebral disc
The aim of the work was an attempt to establish the regularities of the transition of normal age-related changes to pathological ones that determine the prevalence of degenerative diseases of the spinal column in persons of working age, economic costs and low effectiveness of treatment. The article analyzes results of foreign and domestic studies on the problem of intervertebral disc morphogenesis in humans. In this case, ontogenetic features of each intervertebral disc components are separately examined. The generalized results of cartilage endplate studies reflect the histological accessory and age-related changes in the cellular component. In the section «the ontogenesis of annulus fibrosus» features of cellular composition, structural characteristic and peculiarity of collagen fibers course in posterior and anterior parts of annulus fibrosus are described in detail, depending on the age, beginning with the embryonic period. In addition, there are differences in the structure of annulus fibrosus in the cervical, thoracic and lumbar spine. The ontogenetic features of nucleus pulposus concern the collagen fibers and their location, taking into account the age and the spinal column. Various views on the origin of the cells of the nucleus pulposus, changes in the cellular composition in the process of organism development are set forth. On the basis of a detailed analysis of the presented theoretical material, schemes reflecting the key stages of intervertebral disk embryogenesis as a whole and the morphogenesis of nucleus pulposus have been developed.