The occipital-atlas (C0–C1) and atlas-axis (C1–C2) segments join the head to the most mobile region of the spine. The lack of intervertebral discs, the horizontal nature of the joints, and the ...
The specialized anatomy of the upper cervical spine (UCS), comprised of the occipital-atlas (C0–C1) and atlas-axis (C1–C2) segments, produces complex three-dimensional movements and subsequently is ...