Before I start explaining how Sword Swallowers actually swallow, here’s a little disclaimer…

Sword swallowing is dangerous.  It can cause oesophageal perforation, gastrointestinal bleeding and much more. So don’t try this unless you have been trained and supervised by professionals.

Structures of of the Oral Cavity & Pharynx
Before we try to visualise where a sword might fit in a person’s anatomy, let’s orient ourselves to the structures of the oral cavity and pharynx.

In the oral cavity we find; the tongue, teeth, uvula, and the hard and soft palates.


The pharynx sits inferior to the nasal cavity and posterior to the oral cavity. It is the passageway from the mouth and nose to the oesophagus. The pharynx is divided into 3 regions;

1. Nasopharynx
2. Oropharynx
3. Laryngopharynx

Both the Nasopharynx and Laryngopharynx regions are considered airways while the Oropharynx has shared involvement in respiration and digestion. Since we are interested in the structures for swallowing we will look at the structures of the Oropharynx;

• Epiglottis
• Cricopharyngeal Sphincter/Upper oesophageal sphincter

Swallowing a Sword
Now, here is the part where we find out where the sword actually goes.

Sword swallowers are trained to relax the Cricopharyngeal sphincter (i.e. the sphincter at the entrance to the oesophagus) so the sword can pass through the mouth, pharynx and oesophagus with no contact. In a normal swallow the Cricopharyngeal spincter does not open on its own rather, it is pulled open with the superior and anterior movement of the larynx while the bolus widens the sphincter on passing.

The positioning of the head must be correct to line up the mouth with the Cricopharyngeal sphincter and stomach.  If it is not lined up correctly it is likely that the sword will pierce the sphincter or pharyngeal walls.

Also, sword swallowers must train to overcome the gag reflex. This is achieved by causing repetitive gags, desensitising the reflex. Damage to the oesophagus, pharynx and oral cavity is usually caused during this training by the stomach acid that is brought up during the gag desensitisation.

Finally, sword swallowers must relax the upper gastrointestinal tract from squeezing against the sword as it passes.

This relaxation of the sphincter can cause permanent misshaping of the sphincter muscle and a permanent open position increasing the risk of reflux. The reflux can cause damage to linings of the tract and teeth etc. And of course, perforation of any of the linings from mouth to stomach can occur from the sword.

Ninja Random Fact
Sword-swallowers have done a great deal for modern medicine and endoscopic techniques. In 1868 Dr. Adolf Kussmaul of Freiburg, Germany performed the first esophagoscopy on a sword-swallower using a rigid 47 cm tube, mirrors, and a gasoline lamp.

Finally to wrap things up check out this Discovery Channel Episode featuring Dan Meyers, to take an inside look on Sword Swallowing.
References

• Witcombe, B., and D. Meyer. “Sword Swallowing and Its Side Effects.” BMJ 333, no. 7582 (December 23, 2006): 1285–1287. doi:10.1136/bmj.39027.676690.55.

Photos

• Sword Swallowing by Ruben Bos
• Oral Cavity adapted by Aaron Sparshott
  (Originals: Patrick J. Lynch & Drcamachoent)
• Longitudinal view of pharynx adapted by Aaron Sparshott
  (Original: Grays Anatomy)