"The results of XCT scanning and 3D manipulation reveal a complex internal architecture of the azhdarchid cervical vertebra. Clearly visible is an approximately centrally located bony neural tube attached to the centrum wall (centrum tube) by helically arranged radial, spoke-like trabeculae (Figure 2. See also Videos S1 and S2). These are arranged as complimentary opposed helices (clockwise vs anticlockwise) and are often fused where they cross over. Superficially, looking along the length of the centrum internally the radial trabeculae resemble bicycle wheel spokes (Figures 2B and 2D). The arrangement is somewhat irregular and so the helices are not perfect, but this likely reflects changes in the stress regime along a centrum that is not a perfect cylinder. The “spokes” are inclined posteriorly or anteriorly, while still displaying the radial architecture (Figures 2B and 2D). Some “spokes” bifurcate and branch, especially toward the centrum outer wall (Figure 2A, 2C, and 2E). Toward the dorsal part of the centrum (neural arch) and the prezygapophyses the trabeculae are more densely arranged and are orientated more randomly (Figure 2A, 2C, and 2E). Trabeculae are also present along the interior wall of the vertebra, presumably providing support and increasing its strength. The “spokes” have varying diameters, with an average of 1.16 mm."
https://www.cell.com/iscience/fulltext/ ... 21)00306-0
Jonathan
