How does the rectum work and how does it work?
Last reviewed: 23.04.2024
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The rectum is nothing more than one of the main parts of the gastrointestinal tract, which is the last section of the colon. In an adult, the length of the rectum is 13 -23 centimeters and is located in the pelvic region. To understand why hemorrhoids occur, let's look at the peculiarities of the rectum.
What is the rectum and what does it consist of
The diameter of the rectum varies in different ways (2.5 - 7.5 centimeters). The beginning of the rectum takes from the sigmoid colon, only at the end it ends with a hole - it is called the anal.
In fact, the rectum is not straight, as it has two bends, and they are located in the longitudinal plane. The very first bend is called sacral. This curve is concave toward the sacrum and ends behind a bulge. The second bend is called the perineal, since its bulge is directed forward and it most directly represents the bowing of the intestine through the tailbone.
Sections of the rectum
The rectum can be divided into three different sections. The lowest and narrowest is called perineal, in other words, it can be called the anal canal. This channel performs the function of opening outward (anus). Its length is only 2-4 centimeters.
Above the anal canal is the widest part of the rectum, its length varies from 10 to 12 centimeters, it is called the ampoule. The third compartment of the rectum is called “nadampular”, compared with the ampoule, this section is small, only 5-6 centimeters long.
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The tailbone is located directly behind the rectum, and there is also the sacrum. In front of the rectum in men in this zone are the ampoules of the vas deferens, the prostate gland, the seminal vesicles and, of course, the bladder. Women in this area are the uterus and vagina. In the figures it is possible to remarkably consider the difference in how the rectum and closely located organs are located.
Rectal protection
Several layers of protection are on the walls of the rectum itself. As we have already said, the upper part, which is nadampular, is under the reliable protection of the peritoneum, with a thin and very transparent film (shell) on the outside. The anal and ampullary channels are covered with reliable layers, formed from fats and connective fibers, it does not apply to the peritoneum.
The rectum also has a middle layer, which is firmly protected by a pair of rows of muscles. Muscle fibers are outside (they are longitudinal). And the longitudinal muscle fibers inside contain circular fibers of the same composition, which are called the internal sphincter, it is also called the pulp, and surrounded by the external sphincter, so that the masses of feces close and do not fall prematurely outwards.
The sphincter fibers are securely interconnected and attached in a circular principle to the anus.
Rectal mucosa
The mucous membrane is the wall of the rectum (inner wall). Incredibly thin layers of the mucous membrane are separated from the muscle layer. It is thanks to these ultra-thin layers that the muscular mobility of connective tissues is formed.
The epithelial cells in the form of a cylinder form the mucous membrane of the rectum. They also consist of intestinal glands, they are called mucous and goblet. They have the ability to highlight the secret in the form of mucus. It is designed to prevent wounds, scratches and other damage to the walls of the rectum, when it passes fecal masses. The mucus also serves as a lubricant for the feces, which more quickly pass through the rectum. Follicles - small lymphoid nodules - are also located in the rectum.
Rectal folds
When the rectum is not filled with feces, its mucous is able to form folds - there are many of them, and they go in different directions. Two or three folds of the rectum go across, next to them are the fibers of the muscle layer, which go in a circle. Their turn is obtained in the form of a screw, and they are located in the ampulla of the rectum. There are also other folds that are not permanent, they are longitudinal, and straighten when the gut is filled.
In the area of the anus the mucous forms more folds - they are from 6 to 10. These folds are constant, they are called funny - anal posts. Located at the anus and at the base of their elevation in the form of a ring. Here is the place where the mucosa of the rectum forms a transition into the skin of the anus - the anus.
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Rectal blood supply system
To have a clear idea of why hemorrhoids occur, it is important to understand how the blood supply system of the rectum. The fact is that hemorrhoids are a disease that affects the blood vessels located in the submucosal layer of the rectum. It is because of the violation of their structure and work that a person suffers so much from pain in the area of the anus.
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The work of the five arteries
Five arteries work to trigger blood flow to the rectum. Or rather, not into the intestine itself, but to it, to its submucosal layer. One of these arteries is not a paired artery, it is at the top and is called hemorrhoidal. This artery is the end of the inferior artery, which is called the mesenteric.
So, the hemorrhoidal artery has an important role - it carries blood flow to the back of the rectum. These are the areas located above the ampoule and in the part of the ampoule (we have already talked about them).
But there are 4 more arteries that carry blood to the rectum. They create pairs. These pairs are located on the right and left, in the middle and at the bottom of the rectum. They end the hypogastric arteries.
These arteries do not work by themselves - they make up a single whole network of arteries that work together harmoniously for the benefit of our body. Arteries are interconnected vertically and horizontally in the walls of the rectum.
Venous system of the rectum
This is a very important system that provides in the rectum outflow of blood running through the veins. Blood runs from smaller wreaths to larger ones, then runs through the arteries.
Where is the network of veins in the rectum? Its location is in the layer called submucosal (we already know about it). The most solid part of the rectum is the final one; in it the arteries and veins do not branch to the smallest capillaries, but stretch directly to the so-called anal pillars. From this, in the rectum cavernous bodies are formed, located under the mucous membrane. These bodies are also called cavernous.
When a person develops hemorrhoids, these cavernous bodies swell and cause pain reflexes in a person, sometimes unbearable. Such is the anatomical features of the rectum.
Why do hemorrhoids have bumps in the anus?
And this is just swell cavernous or cavernous bodies. They are permeated with many tiny wreaths that look like grapes. When blood accumulates in them, the “grapes” swell and increase. Approximately as the phallus swells during an erection. And then the walls of these cavernous bodies can not withstand the flow of blood and can burst, damage, stretch, and, of course, severely hurt.
Then the person complains of bleeding from the anus. To avoid or stop it, you need anti-inflammatory drugs that will remove the inflammatory process in the cavernous bodies, and at the same time pain. In the meantime, you need to remember that when hemorrhoids occur, the blood from the anus is not dark, but scarlet, because in the cavernous bodies it is such because of the accumulation of oxygen.
The role of the cavernous bodies
Their role is not only to bring us trouble when hemorrhoids attack the body. As physicians have not studied human organism for a long time, they still have not fully understood what roles cavernous bodies perform, except for the accumulation of blood. It is known that they help the sphincter to keep fecal matter, performing the additional function of the clamp.
The cavernous bodies, like the appendix, are similar to the rudiment in the human body. They are found even in babies who have just been born, so the body needs them, maybe even for those roles that we still do not guess.
Nerves of the rectum
In the rectum is a lot of nerve endings. Like the spies who form their network, there are fibers of the parasympathetic and sympathetic nervous systems. So nature conceived anatomically, since there are many reflex zones in the rectum, and signals from these zones are transmitted from the cerebral cortex.
When a boy or girl is born, their rectum is in the shape of a cylinder, has no bends, no ampoules, and the folds of the intestine are not very pronounced.
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The size of the rectum
The length of the rectum of a newborn baby is up to 6 cm, at least 5 cm. The anal columns of young children are very well developed. Ampoule finishes forming until the age of 8 years. And then the rectum forms bends. When a child reaches 8 years old, not only bends form in the rectum - it generally begins to grow very quickly, to elongate and by the age of 14 it becomes longer than three times longer - from 15 to 18 centimeters. And the diameter of the rectum in adolescence - from 3.2 cm to 5, 4 cm
When a person gets older and reaches the age of 50-60 years, his rectum lengthens even more, the curves are no longer so clear, lose their direction, and the mucous membrane of the rectum becomes much thinner. At the same time, the cavernous (cavernous) bodies become thin, empty, so hemorrhoids in men and women over 60-65 years old are very rare.
Work of the rectum to remove toxins
When the rectum is working, it ensures the functioning of the digestive system as a whole. The rectum does the work of eliminating toxins from the body and all unnecessary substances that are no longer needed there.
When a lot of unnecessary slags accumulate in the rectum, they need to be removed from there. And if the rectum does not work normally, these rotten and fetid masses will accumulate there, poisoning the entire body. That is why it is so important that the rectum be healthy and fulfill all its functions of evacuating substances unnecessary to the body.
Statistical role of the rectum
There are major roles of the rectum. There are two main roles. One is statistical, the other is dynamic. The statistical role of the rectum suggests that it will accumulate intestinal excrement and retain them.
If the feces are normal, it will be colored uniform brown. It is dense, shades of brown can vary. In the composition of the normal feces 30% of food residues, and water - 70%. Among the food debris - intestinal epithelium cells, along with dead bacteria. The mass of feces of a healthy person per day will be no more than 350 grams.
When fecal masses accumulate in the rectum, it may become wider, and the folds of the rectum (its mucosa) smooth out. The feces are retained in the rectum by means of the anal pulp, because the walls of the anus are tightly compressed. The anal sphincter is designed to ensure that the contents of the intestine do not fall out of it by itself and the gases are not released involuntarily.
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Force of the sphincter
The anal sphincter is a very powerful and strong muscle. Scientific studies show that in a healthy person the strength of the sphincter is such that at rest it reaches 550 grams, and when it diminishes, then at maximum compression this force rises to 850 grams.
When a person is worried about hemorrhoids or other diseases of the rectum, this immediately affects the strength of the sphincter. It becomes weaker almost four times - the force of its compression reaches only from 200 to 300 grams instead of 850. And then the contents of the intestine can spontaneously emerge, and this happens with the most common household actions - coughing, squatting, laughing, sneezing, and simple walking. In addition to feces, there are no gases in the rectum, liquid feces, and this unpleasant process is permanent - as long as the rectum is unhealthy.
The dynamic role of the rectum
This role is no less important than the first - statistical. It is characterized by a feature of the rectum to evacuate out of the body what it does not need: fecal masses, foreign substances. Namely, due to the dynamic function of the rectum, a person is able to defecate. This is a rather complex physiological reflex process, about which Academician Pavlov wrote. He spoke in his lectures about the need for the process of defecation can be found through the signals of the sensory nerves of the rectum.
This means that when the walls of the rectum are irritated by the feces that have accumulated there, there is a signal through reflex endings that it is time to evacuate them from the rectum.
Sometimes it happens that a person feels the urge to evacuate feces from the rectum when it is empty. This means that there are failures in her work. For example, with diseases such as ulcerative colitis, hemorrhoids, infections that have penetrated the intestines.
Muscles involved in defecation
Muscle fibers play the most direct role in the process of defecation. These muscle fibers are located on the intestinal walls. They are joined by the abdominal muscles, which we so persistently do not want to swing. And in vain: it would significantly strengthen the body, because human health depends on the success of the process of defecation.
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How does defecation occur?
When the process of defecation begins, the person inhales deeply, the glottis closes, and the sphincter of the anus weakens his bench, relaxes, and the abdominals become tense. If the abdominals are weak, the person will not be able to produce a normal defecation act, it takes a long time to press, the rectal stools may be weak.
When a person makes a deep sigh, the diaphragmatic muscle descends, and the abdominal cavity shrinks and decreases in volume. At this time, a lot of pressure is created in the abdominal cavity, and the stool is released through the anus. This pressure is so strong that it reaches 220 mm of water pressure, and this is more than one and a half times higher than the level of arterial pressure created by blood flow.
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Patterns of defecation
The process of defecation, like any other processes occurring in the body, has its own laws. Scientists tracked these patterns and found that defecation is of two types: single-stage and two-stage.
During simultaneous bowel movements, the rectum is able to throw out its contents at one time. If the defecation is two-moment, then the fecal masses are released by the intestines not in one go, but in parts. It can take from three to seven minutes. So, with a two-moment ejection of feces, a person is forced to stay in the toilet for more than seven minutes, since with the first act of ejection of fecal masses, he still has the feeling that the process is not over.
Both the first and the second type of defecation is normal and peculiar to a person - these are just anatomical features that do not pose a health hazard, given the properties of their contraction.
Long defecation
It so happens that a person cannot defecate for more than 15 minutes. Then the process takes up to half an hour. All this time, a person is trying to strain the fecal mass out of the rectum in a strained way.
Instead of waiting, waiting for the next contraction of the intestinal walls and pushing out the fecal masses in a period of 7-15 minutes, the person begins to panic and push them out, pushing. And then constant tension in the abdominals causes an overstrain in the veins of the rectum, in particular - in the cavernous (cavernous) bodies that are already familiar to us.
This causes hemorrhoids to develop, as the cavernous bodies swell and become inflamed. Cracks and inflammation may also develop in the anus; the rectum may begin to fall out of fruitless attempts to strain it.
Therefore, with a significantly slowed bowel process, which is accompanied by pain in the anus, you should consult a doctor for advice. A proctologist can help you.
Defecation type statistics
Studies show that up to 70% of people experience single-stage defecation. Then two-moment defecation is experienced - otherwise it can not be expressed - up to 25% of people. The rest of the people make a defecation of a mixed type.
There are exercises that allow a person to achieve one-stage, the most convenient type of bowel movement for them. How to do them, you need to consult a proctologist.
As for patients with hemorrhoids, up to 90% of them suffer from the fact that they have a two-stage type of bowel movement. They need to be especially careful during feces and to use the natural processes characteristic of the rectum, that is, the time of its reduction.
Why self-medication is dangerous
Often a person does not pay attention to the type of his bowel movement and considers it simply a simple inconvenience, unaware that it causes irreparable harm to his body.
If a person suffers from constipation, if he develops hemorrhoids, it is not necessary to self-medicate, because with the incorrectly chosen methods the rectum may become covered with cracks from the inside or outside, there may be bleeding from swollen cavernous bodies, there may be a danger of delaying fecal masses in the rectum and poisoning body toxins. No need to neglect these symptoms and contact the clinic at the first signs of pain and discomfort in the rectal area.