Anal Fissure: Information & Doctors Specializing in Anal Fissures

Depending on how long the tear in the mucous membrane has been present, it is referred to as an

• acute anal fissure or
• a chronic anal fissure.

An acute anal fissure lasts less than six weeks, while one that persists longer is referred to as a chronic anal fissure.

In the chronic form, an anterior fold, scar tissue, and significant inflammation are often present at the lower part of the fissure.

In addition, anal fissures are classified as primary or secondary depending on the cause. In secondary forms, the fissure is caused by another underlying condition, such as injury, infection, or childbirth. This is not the case with primary anal fissures.

Anal fissures should be distinguished from rhagades. These are tears in the skin around the anus, not tears in the mucous membrane of the anal canal.

Most anal fissures are located at the lowest part of the anal opening, facing the back. The fissure may be visible from the outside. However, it may also be internal and can only be detected upon closer examination of the anal canal.

The most important symptom of an anal fissure is a sharp pain during bowel movements. Blood on the stool or on toilet paper is also common.

Many patients report a burning sensation after a bowel movement, itching, or a sensitive anus.

In cases of chronic anal fissures, changes may occur around the tear in the mucous membrane. These include enlarged anal papillae—nodules in the mucous membrane about the size of a pinhead. In an anal fissure, they can grow to the size of a cherry. In such cases, they are also referred to as anal polyps or anal fibromas.

In addition, marisks may develop. Marisks are skin folds around the anus and are therefore also referred to as anal folds or pre-anal folds.

The symptoms can often last for hours, and the pain frequently leads to constipation, as bowel movements are delayed or suppressed.

An anal fissure is a small wound in the mucous membrane of the anal canal © bilderzwerg | AdobeStock

In most cases, no specific cause for the anal fissure can be identified. Doctors then refer to it as a primary anal fissure.

The mechanism behind the development of an anal fissure has not yet been fully elucidated. However, it is believed that

• constipation and hard stools, as well as
• soft or diarrhea-like stools persisting over a longer period of time

play a role in their development.

As a result of the pain caused by the tear, the sphincter muscle contracts spasmodically. The sphincter muscle surrounds the anal canal and regulates the passage of stool. This increased pressure from the sphincter muscle impairs blood flow to the mucous membrane. This, in turn, has a negative effect on wound healing.

Thus, an acute anal fissure can develop into a chronic condition.

Secondary anal fissures are tears that result from another disease or injury. Triggers for a secondary anal fissure can include:

• mechanical injuries,
• childbirth,
• surgery,
• inflammatory conditions (such as Crohn’s disease), or
• bacterial or viral infections (such as syphilis or chlamydia).

Risk factors include conditions that contribute to constipation and hard stools, and thus increased pressure in the sphincter muscle. These include, for example,

• a low-fiber diet,
• being overweight, and
• hypothyroidism
• mechanical strain on the anus
• local inflammation

Other risk factors include the insertion of foreign objects into the anal canal and rough anal intercourse.

To diagnose an anal fissure, the doctor first examines the anus and the anal canal. Often, the examiner can already see the anal fissure by spreading the buttocks apart. It is also usually possible at this stage to distinguish between an anal fissure and a hemorrhoid.

Typically, the proctologist then palpates the anal canal with a finger (digital rectal examination). This examination is usually painful in cases of acute anal fissures and is not always necessary.

A chronic anal fissure is less painful. In such cases, the doctor may detect scar tissue and hardening during a digital rectal examination.

Using an anal speculum or a proctoscope (a short tube with a light source), the doctor examines the anal canal. This proctoscopy is also known as

• anal endoscopy,
• rectal endoscopy, or
• rectal endoscopy

. 

This examination provides information about changes in the anal canal that present with symptoms similar to those of anal fissures and must therefore be ruled out.

In cases of unclear findings or suspected secondary fissures, imaging techniques may be used, e.g.,

• magnetic resonance imaging (MRI),
• an ultrasound examination (endosonography),
• a colonoscopy, or
• a tissue sample (biopsy).

These procedures are used to rule out other conditions or to diagnose underlying conditions.

Conservative treatment is the primary focus of therapy and is used in nearly all acute cases. The goal of treating an anal fissure is to improve stool consistency, relax the sphincter muscles, and reduce pain and inflammation.

A high-fiber diet is recommended to promote soft, well-formed stools. Drinking at least 2 liters of fluid per day also aids digestion.

An ointment containing local active ingredients, such as nitroglycerin or calcium channel blockers, improves blood flow and reduces spasm of the sphincter muscle. Sitz baths can also be soothing and help relieve muscle spasms. This treatment is recommended for at least six to eight weeks. If these measures are unsuccessful, further treatment is usually considered.

If the anal fissure does not heal after a sufficiently long course of conservative treatment, surgical intervention should be considered. This is usually performed under anesthesia and aims to permanently relieve spasm of the sphincter muscle and allow healing to occur.

The most common procedure is a sphincterotomy. In this procedure, a small portion of the internal sphincter muscle is cut to reduce tension. 

Another option is the injection of botulinum toxin, which temporarily relaxes the muscles. 

In advanced cases, a mucosal or skin flap graft may be used.

Acute fissures often heal spontaneously, especially with early treatment and consistent adherence to recommended measures.

An untreated fissure carries the risk of becoming chronic. 

The prognosis is very good with adequate treatment. Surgical interventions also have high success rates, though there is a small risk of temporary—or, rarely, permanent—incontinence. 

A regular, high-fiber diet is important for prevention and to avoid relapses.

Good bowel regularity prevents irritation and further tearing of the skin. Regular exercise and avoiding excessive straining are helpful measures

What is an anal fissure?

An anal fissure is a painful tear in the lining of the anal canal.

What are the symptoms of an anal fissure?

It is characterized by pain during bowel movements, a burning sensation, itching, and slight bleeding.

How long does it take for an anal fissure to heal?

An acute anal fissure usually heals within six to eight weeks if treated consistently.

Can an anal fissure become chronic?

Yes; if symptoms persist for more than six weeks or healing does not occur, it is considered a chronic condition.

What causes anal fissures?

Anal fissures are often caused by constipation, hard stools, straining during bowel movements, and the resulting tearing of the anal mucosa.