RT Journal Article T1 Fetal cervical zygapophysial joint with special reference to the associated synovial tissue: a histological study using near-term human fetuses A1 Kitamura, Kei A1 Hayashi, Shogo A1 Jin, Zhe Wu A1 Yamamoto, Masahito A1 Murakami, Gen A1 Rodríguez Vázquez, José Francisco A1 Yamamoto, Masahito AB Human fetal cervical vertebrae are characterized by the large zygapophysial joint (ZJ) extending posteriorly. During our recent studies on regional differences in the shape, extent, and surrounding tissue of the fetal ZJ, we incidentally found a cervical-specific structure of synovial tissues. This study aimed to provide a detailed evaluation of the synovial structure using sagittal and horizontal sections of 20 near-term fetuses. The cervical ZJ consistently had a large cavity with multiple recesses at the margins and, especially at the anterior end, the recess interdigitated with or were located close to tree-like tributaries of the veins of the external vertebral plexus. In contrast to the flat and thin synovial cell lining of the recess, the venous tributary had cuboidal endothelial cells. No or few elastic fibers were identified around the ZJ. The venous-synovial complex seems to be a transient morphology at and around birth, and it may play a role in the stabilization of the growing cervical ZJ against frequent spontaneous dislocation reported radiologically in infants. The venous-synovial complex in the cervical region should be lost and replaced by elastic fibers in childhood or adolescence. However, the delayed development of the ligament flavum is also likely to occur in the lumbar ZJ in spite of no evidence of a transient venous-synovial structure. The cuboidal venous endothelium may simply represent the high proliferation rate for the growing complex. PB Korean Association of Anatomists SN 2093-3665 SN 2093-3673 YR 2021 FD 2021-03-31 LK https://hdl.handle.net/20.500.14352/109282 UL https://hdl.handle.net/20.500.14352/109282 LA eng NO Kitamura K, Hayashi S, Jin ZW, Yamamoto M, Murakami G, Rodríguez-Vázquez JF, Yamamoto H. Fetal cervical zygapophysial joint with special reference to the associated synovial tissue: a histological study using near-term human fetuses. Anat Cell Biol. 2021 Mar 31;54(1):65-73. doi: 10.5115/acb.20.265 DS Docta Complutense RD 17 abr 2025