MORPHOGENESIS OF HUMAN EPIDURAL SPACE IN THE EMBRYONIC AND EARLYFETAL PERIODS

Epidural space development was studied in 51 embryos and early fetuses aged 4-13 weeks sectioned serially, using histological and embryological methods of plastic and graphic reconstruction. Three stages were determined in the development of the epidural space: I - primary epidural space (embryos of 16-31 mm crown-rump length [CRL]); II - reduction of the primary epidural space (embryos of 35-55 mm CRL); III - secondary s epidural pace (embryos of 60-70 mm CRL and fetuses of 80-90 mm CRL). Morphogenesis of the primary epidural space is determined by the forming influence of the spinal cord and its dura mater and that of the secondary one - by the walls of the spinal canal. In the correlation chain: the spinal cord - spinal cord dura mater - spinal canal, the latter two elements being under the inducing influence of the first one, determine the morphogenesis of the epidural space through the system of morphogenetic correlations. These correlations are manifested in the form of time-conjugated connection between the formation of the parts of spinal cord dura mater and the spinal canal causing the staged formation of the epidural space in ventrodorsal and craniocaudal directions. The same morphogenetic correlations also determine the stages in the development of the epidural space.

spinal cord, dura mater, epidural space, morphogenesis