Inability to belch or “burp” occurs when the upper esophageal sphincter (cricopharyngeus muscle) loses its ability to relax in order to release the “bubble” of air. The sphincter is a muscular valve that encircles the upper end of the esophagus just below the lower end of the throat passage. If looking from the front at a person’s neck, it is just below the “Adam’s / Eve’s apple” and more specifically, directly behind the cricoid cartilage. If you care to see this on a model, look at the photo below. That sphincter muscle relaxes for about a second every time we swallow saliva, food, or drink. All of the rest of the time it is contracted. Whenever a person belches, the same sphincter needs to let go for a split second in order for the excess air to escape upwards. In other words, just as it is necessary that the sphincter “let go” to admit food and drink downwards in the normal act swallowing, it is also necessary that the sphincter be able to “let go” to release air upwards for belching.
People who cannot release air upwards are miserable. They can feel the “bubble” sitting at the mid to low neck with nowhere to go. Or they experience gurgling when air comes up the esophagus only to find that the way of escape is blocked by a non-relaxing sphincter. It is as though the muscle of the esophagus continually churns and squeezes without success. The person so wants and needs to burp, but can’t. Sometimes this can even be painful. Such people often experience abdominal bloating as the air must make its way through the intestines before finally being released as flatus.
For people who experience this problem to the point of discomfort and reduced quality of life, here is one approach: First, a videofluoroscopic swallow study, perhaps with effervescent granules. This establishes that the sphincter works normally in a forward (antegrade) swallowing direction, but not in a reverse (retrograde) burping or regurgitating fashion. Along with the symptoms described above, this establishes the diagnosis of retrograde-only cricopharyngeus dysfunction (non-relaxation).
Second, a treatment trial involving placement of Botox into the malfunctioning sphincter muscle. The desired effect of Botox in muscle is to weaken it for at least several months. The person thus has many weeks to verify that the problem is solved or at least minimized. The Botox injection could potentially be done in an office setting, but we recommend the first time (at least) placing it during a very brief general anesthetic in an outpatient operating room. That’s because the first time, it is important to answer the question definitively, that is, that the sphincter’s inability to relax when presented with a bubble of air from below, is the problem.
For a few months at least, patients should experience dramatic relief of their symptoms. And, early experience suggests that It may be that this single Botox injection allows the system to “reset” and the person may never lose his or her ability to belch. Of course, if the problem returns, the individual could elect to pursue additional Botox treatments, or in a truly severe case, might even elect to undergo endoscopic laser cricopharyngeus myotomy.
Photos of the cricopharyngeus muscle:
1. The highlighted oval represents the location of the cricopharyngeus muscle.
2. The cricopharyngeus muscle in the open position.
3. The cricopharyngeus muscle in the contracted position.