The pathology of anal fissures
BETTER UNDERSTANDING, BETTER HEALING!
Anal fissures should not be confused with anal fistulas.
While the first is very frequent, the second occurs only seldomly.
This particular section addresses anal fissures.
Anal fissures usually develop during childhood or adolescence. At this stage of life, rectums are highly elastic and can therefore accumulate a large amount of fecal matter. We’ve all heard how common it is for a young child to clog the toilet when going to the bathroom.
In these conditions, the emptying of the fecal bolus can cause internal sphincter hypertonia—this is the etiological hypothesis. In fact, when rectal manometry is performed (measurement of the pressure of the anal canal), it is observed that the internal sphincter contracts excessively and for a prolonged period.
Subsequently, the evacuation of a large bowel movement, or any other cause of sudden distension of the anal canal (such as explosive diarrhea), can lead to a recurrence of the fissure and cause a new internal sphincter spasm attack.
This leads to the following symptoms of anal fissure:
- tear in the anal canal, which causes mostly local bleeding (blood on toilet paper) and a burning sensation
- internal sphincter spasm, which is extremely painful
- a small flap of skin—referred to as a skin tag—can sometimes appear at the lower extremity of the tear
- a fibrous cluster—referred to as a fibrous polyp—can sometimes form at the lower end of the tear
The anal sphincter system consists of two sphincters: the large external sphincter, which is under voluntary control, and the internal sphincter, which is an autonomous muscle (i.e.: it functions automatically, thus ensuring continence even during sleep). See Anatomy of the Rectum.
Anal fissure examinations are quite straightforward:
- On external examination, the anus is contracted, forming skin folds
- When a finger is inserted, there is an intense contraction of the internal sphincter (this contraction is graded from Level 1 to 4)
- Digital examination causes pain, which is more intense in the quadrant where the fissure is located, and increases internal sphincter pressure
- Finally, one can feel the fissure groove: it is most often located posteriorly (when facing the coccyx, it would be located at 6 o’clock). The second most frequent site is the anterior quadrant (at noon).
A fissure in the lateral quadrants should raise suspicion of another diagnosis: Crohn’s disease, ulcerative colitis, tumour or an infectious lesion.
Treating anal fissures
Anal fissures are a recurring issue: a large bowel movement is enough to trigger the problem.
There are two types of situations to consider:
- Acute anal fissure, which has occurred recently
- Chronic anal fissure, which was left untreated or has been an issue for several months or even years
In the first case, treatment is fast: a few days of treatment are enough to solve the problem, provided that the treatment is started early.
In the second case, treatment can take two to eight weeks, and sometimes more, depending on how chronic the problem is.
Resolving constipation
The first step taken for treatment involves improving the quality of the stool:
- by increasing fibre intake in the patient’s diet (See the Diet section)
- by using a stool softener (docusate)
- by artificially increasing fibre intake (Metamucil, Benefibre)
- by reducing intake of foods that cause constipation, notably bananas
Laxatives should be avoided and used only in exceptional circumstances.
Mineral oil should only be used for very short periods of time since regular use greatly impairs the absorption of several vitamins (A, D, E, K).
Regarding hydration, even if we are traditionally taught to push ourselves to drink larger quantities, recent studies have shown that normal hydration (about 1.5 litres per day for adults) is more than enough and that there is no need to overdo it.
Basic local treatments
There are many basic local treatments available to treat anal fissures and their painful symptoms:
In the acute phase, sitting in a sitz bath (i.e.: plastic bowl placed on the toilet or bidet) filled with moderately warm water quickly relieves pain. Sitting for three to five minutes is generally sufficient. Keep in mind that sitting in a sitz bath for extended periods of time (e.g.: 15 minutes) is not recommended. Also, in this respect, taking a traditional bath is much less effective—and potentially even ineffective.
Ointments and creams available at the pharmacy. Certain preparations contain a combination of cortisone and analgesics, while others contain analgesics only (Xylocaine).
Glycerine suppositories to help evacuate stool (this is the best choice for young children).
Vaseline, which acts as a lubricant and makes stool easier to pass.
Local pharmacological treatment
When these basic methods fail, more powerful products must be used:
- A 2.5% cortisone preparation: used in simpler cases
- A 0.5% nifedipine preparation in Vaseline
- A 0.2% nitroglycerin preparation in Vaseline
Why Vaseline? Simply because its adhesive power facilitates insertion into the canal, without too much loss on the outside, and because of its consistent contact with the wall of the anal canal. Vaseline also helps keep the magistral formula stable up to 6 months.
Nifedipine and nitroglycerin induce sustained relaxation of the internal sphincter. This relaxation of the spasm relieves pain and allows the fissure to heal.
Nifedipine is able to resolve most of the more severe cases.
Nitroglycerin is more powerful than nifedipine, but using it can also cause headaches. It is therefore only used in very rare cases.
Diltiazem 2% is sometimes used instead of nifedipine. This is the case for women who are breastfeeding.
Useful tips
How long to use the treatment
For a case that is being treated for the first time, four to eight weeks is generally sufficient.
For chronic conditions, treatments can take up to four months.
In acute or repeat cases after a long period of rest, symptoms usually resolve with a treatment of one to three weeks.
Is it common for symptoms to recur?
Yes, but they tend to fade over the years. This is especially true when there is proper management of diet and constipation.
What to do if bleeding occurs after treatment
Often a person who has been successfully treated for an anal fissure will begin to experience anal bleeding that was not previously present. In this case, the pain that is typical of anal fissure is generally absent or mild. The release of pressure in the anal canal allows the hemorrhoidal varices, if they were present in the first place, to swell.
As a result, hemorrhoids can emerge (see hemorrhoid grades) or begin to bleed due to trauma.
Bleeding can be abundant in this case and sometimes even drip into the toilet.
What to do in this case
Simply proceed with one or more hemorrhoidal ligations. Ligation, which is often uncomfortable in the presence of a fissure and therefore of sphincter hypertonia, then becomes much easier and more comfortable.
If a person has been treated for a fissure and returns for hemorrhoidal bleeding, it is important to resume the treatment with nifedipine or other drugs so that the ligation procedure does not cause contraction of the sphincter.
While waiting for a ligature, it can be helpful to apply Ihle’s Paste into the anal canal. This often helps reduce bleeding.
In order to help you, we have put at your disposal several useful tips.
