The relationship between the lumbosacral enlargement and the conns medullaris during the period of fetal development and adulthood

The spinal cord is situated within the vertebral canal by the third month o f intrauterine life. The spinal cord possesses two symmetrical enlargements , which constitute the segments of the plexuses: the cervical enlargement f or the brachial plexus and the lumbosacral enlargement for the lumbar and s acral plexus. In our study, we aimed to investigate the relationship betwee n the termination level of the lumbosacral enlargement (TLLE) and that of t he conus medullaris (TLCM) during the period of fetal development and adult hood. We used a total of 75 cases: 25 fetuses (male: 16, female: 9) whose c rown-rump length ranged between 90-190 mm, 25 premature and full-term neona tes (male: 17, female: 8) whose post-menstrual ages ranged between 33-55 we eks, and 25 adults (male: 12, female: 13) aged between 22-72 years. The dis section technique for fetuses, ultrasonography for premature and full-term newborns, and magnetic resonance imaging (MRI) for adults were used to dete rmine lumbosacral enlargement and TLCM. The differences between the TLCM an d the termination level of the largest part of the transverse diameter of t he lumbosacral enlargement were investigated. The differences between the T LLE and TLCM were found in different ratios from the period of fetal develo pment to adulthood. Therefore, during medical treatment and surgical proced ures this should be taken into account to avoid complications.