06-08-2010, 12:18 AM
NMBE 6
The pectinate line (anocutaneous line, dentate line, anorectal junction) is a line which divides the upper 2/3rds and lower 1/3rd of the anal canal. Developmentally, this line represents the hindgut-proctodeum junction.
It is an important anatomical landmark, and several distinctions can be made based upon the location of a structure relative to this line:
Distinction Above pectinate line Below pectinate line
destination of lymph drainage internal iliac lymph nodes,[1] inferior mesenteric lymph nodes[2] (pararectal lymph nodes), superficial inguinal lymph nodes (below Hilton's white line)[3]
epithelium columnar epithelium (as is most of the digestive tract - the line represents the end of the part of the body derived from the hindgut) stratified squamous epithelium (as is most of the skin.)
embryological origin endoderm ectoderm
artery superior rectal artery inferior rectal arteries
vein superior rectal vein inferior rectal vein
hemorrhoids classification internal hemorrhoids (not painful) external hemorrhoids (painful)
nerves inferior hypogastric plexus inferior rectal nerves
The pectinate line (anocutaneous line, dentate line, anorectal junction) is a line which divides the upper 2/3rds and lower 1/3rd of the anal canal. Developmentally, this line represents the hindgut-proctodeum junction.
It is an important anatomical landmark, and several distinctions can be made based upon the location of a structure relative to this line:
Distinction Above pectinate line Below pectinate line
destination of lymph drainage internal iliac lymph nodes,[1] inferior mesenteric lymph nodes[2] (pararectal lymph nodes), superficial inguinal lymph nodes (below Hilton's white line)[3]
epithelium columnar epithelium (as is most of the digestive tract - the line represents the end of the part of the body derived from the hindgut) stratified squamous epithelium (as is most of the skin.)
embryological origin endoderm ectoderm
artery superior rectal artery inferior rectal arteries
vein superior rectal vein inferior rectal vein
hemorrhoids classification internal hemorrhoids (not painful) external hemorrhoids (painful)
nerves inferior hypogastric plexus inferior rectal nerves