Muscle spindles in the human levator veli palatini and palatoglossus
The anterior tonsillar pillar is the mucosa-covered palatoglossus
muscle, and the posterior tonsillar pillar is the mucosa-covered palatopharyngeus muscle.
There is also differential activity of the palatoglossus
, palatopharyngeus, musculus uvulae, and superior pharyngeal constrictor muscles.
In some cases, an increase in the thickness of the lateral pharyngeal wall is commensurate with the increase in muscle mass in the hyoglossus, styloglossus, palatoglossus
, palatopharyngeus, and pharyngeal constrictor muscles; these increases are linked to the need for excessive effort to overcome the increased muscle laxity in snoring or during apnea.
The vector forces of the palatoglossus muscle lend support to this observation; histologic studies by Kuebn and Azzam have demonstrated that the elastic layer of the anterior tonsillar pillar is oriented in a mostly craniocaudal direction between the tongue and the soft palate.
Mortimore et al wrote that upper airway obstruction at the retropalatal level is related to the imbalance between the activity of the levator and tensor veli palatini muscles, which elevate and tense the soft palate, and the activity of the palatoglossus and palatopharyngeus muscles, which depress the soft palate anteroinferiorly.
Electromyographic studies by Mathur et al revealed that palatoglossus muscle activity does not always increase in the supine position.
With a 3-0 polydiaxanone suture (PDS), the palatopharyngeus muscle is attached to the palatoglossus
muscle on either side at the incisional site.
The efficiency of the action of upper airway dilating muscles--such as the genioglossus, geniohyoid, palatoglossus
, palatopharyngeus, stylopharyngeus, and tensor palatini--depends on the proper coordination of their contraction with that of the diaphragm, the vector angles through which they act, and the linear distance through which they contract.