Which structure anchors the thecal sac and conus medullaris to the coccyx?Multiple ChoiceFilum terminaleDenticulate ligamentsPia materCauda equina

The structure that anchors the thecal sac and conus medullaris to the coccyx is the Filum terminale.

Explanation:

• Filum Terminale: It is a fibrous extension of the pia mater and it continues from the conus medullaris (the terminal end of the spinal cord) to anchor the spinal cord to the coccyx. This stabilizes the spinal cord and the thecal sac within the vertebral column.
• Denticulate Ligaments: These are extensions of the pia mater that help anchor the spinal cord to the dura mater, but they do not extend down to the coccyx.
• Pia Mater: This is the delicate innermost layer of the meninges that directly covers the spinal cord, but it does not function to anchor the spinal structures to the coccyx.
• Cauda Equina: This refers to the collection of nerve roots at the lower end of the spinal cord and is not related to anchoring the spinal cord to the coccyx.

Thus, the correct answer to the question is Filum terminale.