Posterior semicircular canal
|Posterior semicircular canal|
|Interior of right osseous labyrinth.|
|Template:Inner ear map/inline|
|Latin||canalis semicircularis posterior|
|Gray's||subject #232 1049|
It is vertical, like the superior, is directed backward, nearly parallel to the posterior surface of the petrous bone. It is part of the bony labyrinth and is used by the vestibular system to detect rotations of the head in the sagittal plane.
It is the longest of the three canals, measuring from 18 to 22 mm.
Its lower or ampullated end opens into the lower and back part of the vestibule, its upper into the crus commune already mentioned.
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.