The transverse rectal folds (valves of Houston) are usually three crescent-shaped shelves inside the rectum, formed by the mucosa and circular muscle. The middle one, on the right side, is the largest and most constant.
| Location | Inner wall of the rectum: superior and inferior folds on the left, middle fold on the right about 7-8 cm from the anus |
|---|---|
| Parts |
|
| Nerve Supply | Inferior hypogastric plexus |
| Blood Supply | Superior rectal artery; Middle rectal artery |
| Venous drainage | |
| Lymphatic drainage |
|
Help support the contents of the rectum and slow the descent of faeces.
The folds are landmarks during sigmoidoscopy and must be negotiated with care during instrument insertion. The middle fold roughly marks the level of the peritoneal reflection, relevant when rectal biopsies are taken.
Rare injury to the rectal wall near a fold during instrument passage.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
