Neurology Lab 2 - Module 1 - Vertebral Column: Page 4 of 5

View the vertebral column.

Using the Highlight tool, identify and highlight the sacrum and coccyx, noting the orientation and anatomical relationships of their segments on the transverse, sagittal and coronal cross-sections. In particular, make certain to review the various sacral foramina and consider the neurovascular structures traversing them.

	What nervous structures traverse the anterior and posterior sacral foramina?
Unlike the cervical, thoracic and lumbar vertebrae, the anterior (ventral) rami exit from the anterior sacral foramina and the posterior (dorsal) rami exit from the posterior sacral foramina.

	What is the sacral hiatus and its clinical importance?
The sacral hiatus is a gap in the posteroinferior sacrum resulting from the failure of the laminae of S5 (and sometimes S4) to fuse. This opening at the inferior end of the sacral canal is easily palpated and used for caudal anesthesia.