Anal Fissures

So another super common thing I see in my practice is an anal fissure.  A fissure is a small tear in the skin in the anus.  I like to describe it to people as a “paper cut in your butt.”  It is small but incredibly painful. The classic textbook presentation is of a patient who comes in and says they feel like they are “pooping glass.”  There is often some bleeding, which can be impressive and scary.  

Fissures are divided into acute vs. chronic.  A fissure is usually caused by aggressive wiping, hard stool or diarrhea.  Small tears will usually heal on their own with dietary modification.  A chronic fissure is one that lasts over 6 weeks.

The cycle of pain:  

The problem with a fissure is that it can become a chronic problem.  The majority of fissures will occur in the midline posterior aspect of the anal area (translation: towards your tailbone).  This is known as the “watershed” area of the anus.  This is the point where blood flow is the lowest- and blood flow is critical for wound healing.  When people have severe pain from the fissure, the internal anal sphincter reflexively tightens.   When it tightens, the blood doesn’t flow there so the fissure cannot heal.  When it doesn’t heal, it keeps hurting and the cycle continues.  Eventually you end up with a chronic open cut, usually a small skin tag above it, and a sphincter with a higher resting tone.

What can cause it?  Recent history of diarrhea, hard stool or excess wiping.  Sometimes spicy food can play a part.  Sometimes you can have a normal stool and a small tear will occur. 

Symptoms:  Pain while pooping is generally the most common symptom.  Most people will feel as if there are sharp pieces of glass in their stool.  It causes pain, burning and aching that can last minutes to hours after having a bowel movement.  Bleeding is also common.  Blood is usually on the toilet paper or in the toilet bowel.  It can seem like a large amount, which can be alarming.  

Treatment:  As mentioned earlier, dietary modification by adding fiber supplements like psyllium husk (Metamucil, etc) and increasing water intake can help.  This will create a fluffy bulky stool that is easy to pass and that will cause minimal additional trauma.  Stool softeners can be added as needed.  Spicy and irritating foods, such as chile peppers, tomatoes, garlic, onions, etc should be eliminated.  Topical agents, like lidocaine cream, zinc oxide, calmoseptine ointment, and coconut oil can be used to help soothe the area.  Sitz baths also provide a lot of relief, especially after a bowel movement.  Wet toilet wipes (sans fragrance) can be helpful but it is important to keep the protected from excess moisture.   

If conservative management doesn’t help, your doctor may add a prescription ointment or cream, usually nitroglycerin or a calcium channel blocker (pharma-speak).  Basically these medications work to help relax the sphincter muscle to allow for blood flow to that area and help heal the fissure.  After 3 months or so, the area will usually heal.  Alternatively, botox can be used to temporarily paralyze the muscle to allow for healing. 

Surgery to fix fissures is still the gold standard.  It is actually a quick and simple procedure called a lateral internal sphincterotomy.  In regular words, it is just cutting a small part of the internal sphincter to allow it to relax a bit- like loosening a belt that is too tight.  This will again allow blood to flow to the area to heal and also cut down on the pain felt with the increased sphincter tone.  Most patients will feel immediate relief of symptoms with this surgery.  There is a small risk of incontinence but it is rare in healthy patients without previous anorectal surgery.