Superior pharyngeal constrictor muscle
Encyclopedia
The superior pharyngeal constrictor muscle is a quadrilateral muscle, thinner and paler than the inferior pharyngeal constrictor muscle
and middle pharyngeal constrictor muscle
.
- the lower third of the posterior margin of the medial pterygoid plate
and its hamulus
(Pterygopharyngeal part)
- from the pterygomandibular raphe
(Buccopharyngeal part)
- from the alveolar process of the mandible above the posterior end of the mylohyoid line
(Myolopharyngeal part)
- and by a few fibers from the side of the tongue
(Glossopharyngeal part)
The fibers curve backward to be inserted into the median raphe
, being also prolonged by means of an aponeurosis
to the pharyngeal spine on the basilar part of the occipital bone
.
The superior fibers arch beneath the levator veli palatini
muscle and the Eustachian tube
.
of food is received in the pharynx, the elevator muscles relax, the pharynx descends, and the constrictors contract upon the bolus, and convey it downward into the esophagus.
Inferior pharyngeal constrictor muscle
The Inferior pharyngeal constrictor, the thickest of the three constrictors, arises from the sides of the cricoid and thyroid cartilage. Similarly to the superior and middle pharyngeal constrictor muscles, it is innervated by the vagus nerve , specifically, by branches from the pharyngeal plexus...
and middle pharyngeal constrictor muscle
Middle pharyngeal constrictor muscle
The middle pharyngeal constrictor is a fanshaped muscle, smaller than the Inferior pharyngeal constrictor muscle.-Origin and insertion:It arises from the whole length of the upper border of the greater cornu of the hyoid bone, from the lesser cornu, and from the stylohyoid ligament.The fibers...
.
Origin and insertion
The four parts of this muscle arise from:- the lower third of the posterior margin of the medial pterygoid plate
Medial pterygoid plate
The medial pterygoid plate of the sphenoid is narrower and longer than the lateral pterygoid plate; it curves lateralward at its lower extremity into a hook-like process, the pterygoid hamulus, around which the tendon of the Tensor veli palatini glides.The lateral surface of this plate forms part...
and its hamulus
Hamulus
Hamus, Hamulus and words derived from them, are morphological or anatomical terms in various branches of biology. They describe structures functioning as, or in the form of, hooks or hooklets.-Derived terms:...
(Pterygopharyngeal part)
- from the pterygomandibular raphe
Pterygomandibular raphe
The pterygomandibular raphe is a tendinous band of the buccopharyngeal fascia, attached by one extremity to the hamulus of the medial pterygoid plate, and by the other to the posterior end of the mylohyoid line of the mandible.* Its medial surface is covered by the mucous membrane of the mouth.*...
(Buccopharyngeal part)
- from the alveolar process of the mandible above the posterior end of the mylohyoid line
Mylohyoid line
Extending upward and backward on either side from the lower part of the symphysis of the mandible is the mylohyoid line, which is the origin of the mylohyoid muscle; the posterior part of this line, near the alveolar margin, gives attachment to a small part of the Constrictor pharyngis superior,...
(Myolopharyngeal part)
- and by a few fibers from the side of the tongue
Tongue
The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...
(Glossopharyngeal part)
The fibers curve backward to be inserted into the median raphe
Median raphe
The term Median raphe can refer to one of two different anatomical structures:* The pharyngeal raphe* The perineal raphe, also known as the "median r. of perineum"...
, being also prolonged by means of an aponeurosis
Aponeurosis
Aponeuroses are layers of flat broad tendons. They have a shiny, whitish-silvery color, are histologically similar to tendons, and are very sparingly supplied with blood vessels and nerves. When dissected, aponeuroses are papery, and peel off by sections...
to the pharyngeal spine on the basilar part of the occipital bone
Occipital bone
The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoidal in shape and curved on itself...
.
The superior fibers arch beneath the levator veli palatini
Levator veli palatini
The levator veli palatini is the elevator muscle of the soft palate in the human body. During swallowing, it contracts, elevating the soft palate to help prevent food from entering the nasopharynx...
muscle and the Eustachian tube
Eustachian tube
The Eustachian tube is a tube that links the nasopharynx to the middle ear. It is a part of the middle ear. In adult humans the Eustachian tube is approximately 35 mm long. It is named after the sixteenth-century anatomist Bartolomeo Eustachi...
.
Relations
The interval between the upper border of the muscle and the base of the skull is closed by the pharyngeal aponeurosis, and is known as the sinus of Morgagni.Action
As soon as the bolusBolus (digestion)
In digestion, a bolus is a mass of food that has been chewed at the point of swallowing. Once a bolus reaches the stomach, digestion begins....
of food is received in the pharynx, the elevator muscles relax, the pharynx descends, and the constrictors contract upon the bolus, and convey it downward into the esophagus.