Topographic and Anatomical Features of the Human Vertebral Column and Spinal Cord at the 18–21 Weeks of Fetal Ontogenesis

Abstract

The aim of study was to identify anatomical features of the vertebral column and spinal cord, as well as their relationships at the stage of the intermediate fetal period of ontogenesis.Material and methods. The research included the study and analysis of the sectional material of 20 human fetuses of both genders at the 18–21 weeks of their development. The material was obtained as a result of abortion on social indications. The complex of morphological methods such as macro-microscopic preparation, N.I. Pirogov technique of preparations of variously-planared sections, preparation of series of histotopogrammes with van Gieson’s staining was used in the study.Results. The study has revealed that the length of the vertebral column varied from 110±4.9 mm to 122±4.7 mm in the investigated period of ontogenesis. The development of the vertebral column curvatures was observed; thoracic kyphosis being found most commonly (in 80% of cases). The transverse size of the vertebral body was larger than the anterior-posterior size of the vertebral column. There was an asymmetry of holes in the transverse processes of the cervical vertebrae. The character of changes in the vertebral canal was defined, the dynamics of these changes was quantitatively described. The morphometry of the spinal cord was performed in correlation with the spinal column. The largest length of the spinal roots was registered at the level of Sc5. The study demonstrated that development of the spinal cord is subject to the rule of bilateral asymmetry: spinal roots of the same segment on the right and left sides are not always symmetrical and may have different length parameters.Conclusion. Thus, the obtained data on quantitative morphometry and topography of the vertebral column and spinal cord at the 18–21 weeks of the human ontogenesis can be used as the anatomical basis for the developing fetal surgery and diagnostic methods.