Anatomy and Physiology series: Pharyngeal Musculature

It's that time again.  Time for some A&P!  Oh yeah!  The next few posts in this series will be just straight-up anatomy.  I'm going to cover pharyngeal musculature here, tongue musculature, palatal muscles, and possibly a few facial and jaw muscles as well.  It's going to be a little while before the physiology really shows up here, because I will also cover the nervous system, at least conceptually, that's in charge of this whole thing before getting into the really interesting physiology of the articulatory system.  On to the pharyngeal musculature!  As you read, remember that the pharynx refers to the space, as well as the structures, above the larynx.  There are three sections of the pharynx, the laryngopharynx, oropharynx, and nasopharynx that I'll refer to just for orientation.

Pharyngeal musculature is biologically big-time involved with swallowing.  As such, these muscles are divided into pharyngeal constrictors and openers.  There are three main pharyngeal constrictors:  The superior pharyngeal constrictor, middle pharyngeal constrictor, and the inferior pharyngeal constrictor.  (Can't tell you how much I loved the easy naming system during my final exam last semester!)  These three constrictors overlap, a bit like shingles, and form the side and back walls of the pharynx.

All three of these muscles have a lot of attachment points, so I won't get into them too much here.  Let's just talk about the main function.  The superior pharyngeal constrictor forms the sides and back walls of the nasopharynx and also a portion of the back of the oropharynx.  It's function is to pull the pharyngeal walls forward and constrict the pharynx.  The middle pharyngeal constrictor and inferior constrictor both constrict the pharynx, but the inferior constrictor is divided into two parts, the cricopharyngeus and the thyropharyngeus.  The cricopharyngeus constricts the upper portion of the esophagus.  

Our pharyngeal openers, or dilators, are:  The stylopharyngeus, and the salpingopharyngeus.  (I always thought that last one sounded like a name for a dinosaur rather than a muscle...maybe it's just me.)

Same image, but the arrow is pointing at the stylopharyngeus.  It originates from the styloid process at the top and inserts into the pharyngeal constrictors and the thyroid cartilage.  The stylopharyngeus opens and elevates the pharynx.

And in the red above, we have the salpingopharyngeus.  This image is looking from behind, as if you could peek through the back of the head to see the pharynx.  This muscle originates from the lower part of the Eustachian tube and inserts into one of the palatal muscles we'll get to later called the palatopharyngeus.  It elevates the side of the pharyngeal walls.

These muscles are pretty closely tied into muscles of the tongue, face, and laryngeal musculature.  In normal speech, these guys don't usually do too terribly much, since they're much happier and better at being swallow muscles, but during singing, they can create issues in terms of constriction if you're compensating for something.  I'll get into some of that a lot later if you hang in here with me.

*Seikel, J. A., King, D. W., & Drumright, D. G. (2010). Anatomy and physiology for speech, language, and hearing. Clifton Park, NY: Delmar.