Umbilicus

The umbilicus is a prominent scar on the abdomen, with its position being relatively consistent among humans.

The skin around the waist at the level of the umbilicus is supplied by the tenth thoracic spinal nerve (T10 dermatome).

The umbilicus itself typically lies at a vertical level corresponding to the junction between the L3 and L4 vertebrae, with a normal variation among people between the L3 and L5 vertebrae.

Parts of the adult navel include the "umbilical cord remnant" or "umbilical tip", which is the often protruding scar left by the detachment of the umbilical cord.

This is located in the center of the navel, sometimes described as the belly button. Around the cord remnant, is the "umbilical collar", formed by the dense fibrous umbilical ring.

Surrounding the umbilical collar is the periumbilical skin.

Directly behind the navel is a thick fibrous cord formed from the umbilical cord, called the urachus, which originates from the bladder.