Dyssynergic Defecation : A Special Case of Constipation

Laurie Bickerton, PT, FCAMPT, AFCI
Registered Physiotherapist – Pelvic Health and Orthopedic Manual Therapist

There are many reasons for constipation, and some really excellent and simple fixes for those. If constipation troubles you, be sure that you have tried the basics first, and really given them a good try. A blog on that can be found here.

What is Dyssynergic Defecation?

Essentially, it is poor co-ordination of the combination of pushing and controlling the anus to open. ‘Dys-’ means poor or painful and ‘synergy’ means together, working at the same time. Defecation, or pooping, is the action that is not working. Dyssynergic defecation is also called anismus. Estimates vary, but about 20% of those with constipation may have this co-ordination issue.

The group of muscles we call the ‘pelvic floor’ help control both bowel and bladder elimination. There are sensors in the walls of the end of the gut (rectum) that tell you, based on stretching, that the bowel is full and ready to empty. You get seated on the toilet, and just as you start to push, the pelvic floor muscles contract at the wrong moment. Effectively, they block the passage of stool. So you are pushing to get the stool out, often straining, and the pelvic muscles, including the sphincters, are tightly contracted. The door is slammed shut.

What Causes The Muscles to Tighten?

The muscles of the pelvic floor clearly need to relax to allow stool to pass out. When there has been sharp pain (from gut problems, hemorrhoids, fissures around the anus, post partum stitches, etc.), the muscles can reflexively tighten. It’s the body over-protecting against the pain or discomfort. An anxious nervous system will tighten the pelvic floor as well. There are some people who just have a slower gut, which is called ‘slow transit time’. Sometimes there has been chronic constipation from childhood, or opiates are taken for other reasons. A decrease in the sensation in the rectum can be the cause. See my blog on retraining the sensation : Constipation and Bowel Urgency. As a person with tight pelvic floor muscles tries to empty, the body tightens just at the moment that pelvic floor muscles should relax. Usually the person sits longer on the toilet and eventually is able to empty. Straining is common, and tends to cause or exacerbate hemorrhoids, worsening the issue. Using fingers to help stool out (digital disimpaction or digital evacuation) is also fairly common.

How Do We Solve This ?

As with so many things physiotherapists do, pelvic physiotherapists can teach you how to co- ordinate the muscles to do what you need to do. There are home exercises, and in the clinic, one of the really useful tools is a balloon catheter. I described the use of balloon catheters, and there is an image in my blog on Constipation and Bowel Urgency. In short, we use a tiny, medical grade balloon, inserted into the rectum to retrain sensation in the rectal walls. It is one form of biofeedback. Then we are able to work on relaxation of the pelvic floor to allow passage of the stool. Co-ordination is trained with the pushing muscles of the abdominal wall and diaphragm, so that they contract as the pelvic floor relaxes.

It is useful to retrain the ability to bear down and expel the balloon. Commonly, this is part of retraining, and can be really helpful for patients with dyssynergic defecation. We develop a new motor pattern with relaxation, so that people go home with something they can practise.

Ano-Rectal Manometry

This is very similar to what physicians or technicians do in anorectal manometry. Your primary care practitioner may send you for an assessment. With more detailed assessment tools, the physician will measure the pressures generated in bearing down, graphs of muscle contraction patterns and timing. In Canada, the waiting list for this is often months long, but it does diagnose the issue, and separate it from other bowel disorders. If your primary care practitioner can refer you to a pelvic health physiotherapist who does balloon catheter work, you can have an assessment and get going on treatment right away. Of course, the physician can also prescribe medications for constipation, and may offer treatments like Botox injections. Talk to your primary care practitioner and see.

Another Factor to Consider

It is important to consider what the nervous system contributes to this : over contraction of the muscles of the pelvic floor. When you stop to consider the number of nerves deep in the pelvis, you begin to appreciate the control of all that goes on: bladder sensation and control, sexual function including arousal, orgasm, ejaculation for men, and everything in the menstrual cycle to growing a baby and delivering it. This is all controlled by a part of the nervous system that most people don’t know about : the autonomic nervous system. It is essentially automatic. It digests food, keeps the heart beating, and generally runs the internal systems without any conscious control from us. It is still part of the body as a whole, and so when the body is stressed, those chemicals impact all of the nervous system.

But How Does the Nervous System Affect My Gut ?

If considered like a thermostat, you can heat things up, or cool them down. Heating them up is the ‘fight, flight, of freeze’ function that we all recognize. Adrenaline is the main chemical that is produced. The cooling down function is sometimes known as ‘rest and digest’, and acetylcholine is key to its function. We all know the feeling of being ‘wound up’ from bad news, traffic, stressful interactions with co-workers or family, etc. Adrenaline courses through our blood vessels, making us jumpy. This response is ages old, and comes from ancestors many hundreds of thousands of years ago. It was critically important for survival to mobilize body systems to hear threats coming, see more clearly, or run. It makes sense that the eyes dilate, tiny muscles in the ear adapt to low frequencies, and the muscles get more blood supply. This is a zero-sum game though. There is only so much energy and blood supply to go around, so organs not being used to flee have their blood supply throttled back. Consider that it would not have been a good survival strategy to stop and spend energy on digestion, take time for elimination of waste, or have sex while a giant beast was stalking you.

This is the nervous system function we have inherited. We have evolved many more functions since, but this ramp up / shut down combination is deeply wired for times of stress. It doesn't serve us particularly well as we wrestle with a deadline, but for so many things the pelvis does, it is truly counter-productive. In the case of constipation, the muscles of the pelvic floor are ‘skeletal’ and thus tighten with adrenaline. The gut slows to a crawl, since digestion is not a priority. Circulation in the pelvic organs generally is decreased. You can appreciate how this

happens after a bunch of small stresses, but also how the body is wired to respond by slowing down defecation and tightening the pelvic floor. Not helpful.

How Can We Reach In to Control The Nervous System?

The single function that is controlled both by our autonomic (automatic) nervous system and our voluntary control is breathing. Astonishingly, we can use breathing in a slow and controlled way, to reach into our nervous systems and turn down the ‘fight, flight or freeze’ signals. Inhalation is a tiny fight, flight or freeze signal and exhalation is a tiny rest and digest signal to the body. What most of the breathing exercises aim to do is have a short inhalation, and a long slow exhalation. That way, you are biasing your system towards rest and digest and all of its chemical signals. It works. Seriously, this is worth the time. It helps your gut settle down, and many people end up having other things in their lives that improve as well. Sleep, sex drive, pain to name a few.

I have had many people come into the clinic who would prefer to skip the breathing or meditation component of the homework. Typically we struggle, and do not have success in the long term, which is frustrating for both of us. I understand the seeming lack of connection between a busy lifestyle and gut function. Many people do not think they are stressed. If you are struggling with constipation or pelvic pain or dysfunction of any sort, this is something you can add on your own at home before you even come in to see one of us.

All of us at Proactive Pelvic Health Centre use breathing and meditation practices in our treatment plans. Dyssynergic defecation is rooted in the control of the pelvic floor muscles. Getting in touch with the sensation and muscle function is so much easier as people begin to use breath work to improve control of their nervous system. The exercises are simple, but they work. They take work, but I have seen results that have astonished me. If you or your medical practitioners suspect dyssynergic defecation, come and collaborate with us to solve it. It’s a team effort between patient and pelvic physiotherapist.