| Abstract: |
The human spine is organized into 7 cervical, 12 thoracic, 5 lumbar, and 5 fused sacral bony segments. Together, these confer structural support and flexibility while also harboring and conveying the spinal cord, its 30 paired nerve roots, and nervous communication among and between them and higher nervous structures. In the mobile suprasacral spine, these dual functions are subserved by bony rings composed of a ventral vertebral body in continuity with posterolateral bony elements at each level that surround and protect the thecal sac and enclosed neural elements. Each level also articulates with adjacent spinal levels, ribs in the thoracic spine, and the cranium or pelvis at the respective cranial and caudal extremes. Varying degrees of ligamentous support confer differing degrees of motion at each level in the axial (rotational), sagittal (flexion/extension), and coronal (lateral bending) planes while maintaining alignment. © 2023 Elsevier Inc. All rights reserved. |
