Natal cleft

Intergluteal cleft
An intergluteal cleft
Details
Identifiers
Latin	Crena interglutealis
FMA	2016
Anatomical terminology []

The intergluteal cleft, also known medically by various synonyms and colloquially as the "butt crack" or "ass crack", is the groove between the that runs from just below the sacrum to the perineum, so named because it forms the visible border between the external rounded protrusions of the gluteus maximus muscles. The intergluteal cleft is located superior to the anus.

Ingrown hair can obstruct hair follicles in the intergluteal cleft, exciting a foreign body reaction, leading to formation of a pilonidal cyst. Secondary tracks may open onto the skin, allowing the cyst to drain a foul smelling discharge, which is known as a pilonidal sinus.

Medical synonyms for the intergluteal cleft include gluteal cleft, natal cleft, anal cleft, clunial cleft, crena analis, crena ani, crena interglutealis, and rima ani.