Jang, Hyung SukCho, Kwang HoChang, HyukJin, Zhe WuRodríguez Vázquez, José FranciscoMurakami, Gen2024-11-062024-11-062015-11-24Jang HS, Cho KH, Chang H, Jin ZW, Rodriguez-Vazquez JF, Murakami G. The Filum Terminale Revisited: A Histological Study in Human Fetuses. Pediatr Neurosurg. 2016;51(1):9-19. doi: 10.1159/0004392841016-229110.1159/000439284https://hdl.handle.net/20.500.14352/110086Previous studies have suggested that secondary neurulation provides no functional neurons but only the filum terminale. However, no studies have confirmed that the coccygeal and lower sacral nerves do not originate from the secondary neural tube but only from the primary tube. To obtain a better understanding of these relationships, we examined sagittal or frontal sections from 20 embryonic and fetal specimens ranging from 6 to 14 weeks of gestation. During the growth of the vertebral column as well as the subsequent upward migration of the caudal end of the dural sac, the secondary neural tube was stretched to maintain the original attachment to the coccyx or the lower sacral vertebra. The filum-like structure showed much individual variability but in all cases appeared to be derived from the stretched neural tube. Intermediate age morphology revealed that the secondary neural tube itself provided an initial filum terminale before the ascent of the dural sac. Given that the coccygeal and lower sacral nerves are likely to originate from the secondary neural tube, these parts of the tube persisted and differentiated into spinal neurons to form the anococcygeal nerves. Likewise, the filum terminale was also most likely to contain some neurons that persisted postnatally. Depending on the timing and site of degeneration of the secondary neural tube, individual variations could occur in proportion to the amount of sensory and motor elements in the anococcygeal nerve supply.engjournal article1423-0305https://doi.org/10.1159/00043928426595116https://karger.com/pne/article-abstract/51/1/9/289161/The-Filum-Terminale-Revisited-A-Histological-Study?redirectedFrom=fulltexthttps://pubmed.ncbi.nlm.nih.gov/26595116/restricted access611Filum terminaleSecondary neural tubeDural sacSacral and coccygeal nerve rootHuman embryoAnatomía2410.02 Anatomía Humana2410.06 Embriología Humana