First AD

Second AD

What structure or anomaly is the arrow pointing to in this image of a 20-week fetal spine?

This is a normal structure seen as a fibrous band extending from the tip of the conus medullaris of the spinal cord to the coccyx. Best displayed in sagittal section, it can be the site of tumors, such as lipomas, or cysts; more often, however, the filum terminale is involved in a condition called tethered cord syndrome.

Pregnancy and Birth

News

Challenge your anatomy skills: Can you identify the spinal structure?

Image IQ: Anatomy of the Fetal Spine

Joe Antony, MD