These are short, thick plates of bone angling dorsomedially from the pedicle. The two laminae meet in the mid-line to form the base of the spinous process. The vertical length of the laminae is shorter than that of the bodies creating posterior gaps in the articulated vertebral column. These gaps are used clinically as the sites for lumbar puncture. The laminae provide surface for muscle and ligament attachment.

The term lamina is Latin for plate, leaf, or thin scale. It describes thin plate-like structures, typically bone.

Lamina arcus vertebrae