The pectinate line (dentate line) is a line which divides the upper two-thirds and lower third of the
anal canal
The anal canal is the part that connects the rectum to the anus, located below the level of the pelvic diaphragm. It is located within the anal triangle of the perineum, between the right and left ischioanal fossa. As the final functional s ...
. Developmentally, this line represents the
hindgut-
proctodeum junction.
It is an important anatomical landmark in humans, and forms the boundary between the anal canal and the
rectum
The rectum (: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. Before expulsion through the anus or cloaca, the rectum stores the feces temporarily. The adult ...
according to the anatomic definition.
Colorectal surgeons instead define the anal canal as the zone from the anal verge to the anorectal ring (palpable structure formed by the
external anal sphincter and the
puborectalis muscle
The levator ani is a broad, thin muscle group, situated on either side of the pelvis. It is formed from three muscle components: the pubococcygeus, the iliococcygeus, and the puborectalis.
It is attached to the inner surface of each side of the ...
).
Several distinctions can be made based upon the location of a structure relative to the pectinate line:
Additional images
File:Rectoanal jxn.JPG, Microscopic cross section of the anorectal junction
File:Anorectum-en.svg , Anatomy of the anus and rectum
File:Gray1078.png, Coronal section of rectum and anal canal
References
External links
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{{Authority control
Digestive system
Anatomic Landmarks