Styloid process (temporal)
Encyclopedia
The styloid process is a pointed piece of bone that extends down from the human skull, just below the ear.

Structure

The styloid process is a slender pointed piece of bone just below the ear. It projects down and forward from the inferior surface of the temporal bone
Temporal bone
The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebrum.The temporal bone supports that part of the face known as the temple.-Parts:The temporal bone consists of four parts:* Squama temporalis...

, and serves as an anchor point for several muscles associated with 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...

 and larynx
Larynx
The larynx , commonly called the voice box, is an organ in the neck of amphibians, reptiles and mammals involved in breathing, sound production, and protecting the trachea against food aspiration. It manipulates pitch and volume...

.
  • Its proximal part (tympanohyal) is ensheathed by the vaginal process of the tympanic portion.
  • Its distal part (stylohyal) gives attachment to the following:
    • stylohyoid ligament
      Stylohyoid ligament
      In connection with the stylohyoideus muscle a ligamentous band, the stylohyoid ligament, may be described.It is a fibrous cord, which is attached to the tip of the styloid process of the temporal bone and the lesser cornu of the hyoid bone....

    • stylomandibular ligament
      Stylomandibular ligament
      The stylomandibular ligament is a specialized band of the cervical fascia, which extends from near the apex of the styloid process of the temporal bone to the angle and posterior border of the angle of the mandible, between the Masseter and Pterygoideus internus.This ligament separates the parotid...

    • styloglossus
      Styloglossus
      The Styloglossus, the shortest and smallest of the three styloid muscles, arises from the anterior and lateral surfaces of the styloid process, near its apex, and from the stylomandibular ligament....

       muscle (innervated by the hypoglossal nerve
      Hypoglossal nerve
      The hypoglossal nerve is the twelfth cranial nerve , leading to the tongue. The nerve arises from the hypoglossal nucleus and emerges from the medulla oblongata in the preolivary sulcus separating the olive and the pyramid. It then passes through the hypoglossal canal...

      )
    • stylohyoid muscle
      Stylohyoid muscle
      The stylohyoid muscle is a slender muscle, lying anterior, and superior of the posterior belly of the digastric muscle. It shares this muscle's innervation by the facial nerve, and functions to draw the hyoid bone backwards and elevate the tongue....

       (innervated by the facial nerve
      Facial nerve
      The facial nerve is the seventh of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity...

      )
    • stylopharyngeus muscle (innervated by the glossopharyngeal nerve
      Glossopharyngeal nerve
      The glossopharyngeal nerve is the ninth of twelve pairs of cranial nerves . It exits the brainstem out from the sides of the upper medulla, just rostral to the vagus nerve...

      )


The stylohyoid ligament extends from the apex of the process to the lesser cornu
Lesser cornu
The lesser cornua are two small, conical eminences, attached by their bases to the angles of junction between the body and greater cornua of the hyoid bone....

 of the hyoid bone
Hyoid bone
The hyoid bone is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies at the level of the base of the mandible in the front and the third cervical vertebra behind.Unlike other bones, the hyoid is only distantly...

, and in some instances is partially, in others completely, ossified.

A small percentage of the population will suffer from an elongation of the styloid process and stylohyoid ligament calcification. This condition is also known as Eagles Syndrome. The tissues in the throat rub on the styloid process during the act of swallowing with resulting pain along the glossopharyngeal nerve. There is also pain upon turning the head or extending the tongue. Other symptoms may include voice alteration, cough, dizziness, migraines, occipital neuralgia , pain in teeth and jaw and sinusitis or bloodshot eyes.

Development

The styloid process arises from endochondral ossification
Endochondral ossification
Endochondral ossification is one of the two essential processes during fetal development of the mammalian skeletal system by which bone tissue is created. Unlike intramembranous ossification, which is the other process by which bone tissue is created, cartilage is present during endochondral...

 of the cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...

 from the second branchial arch
Branchial arch
In the development of vertebrate animals, the pharyngeal arches are anlage for a multitude of structures. In humans, they develop during the fourth week in utero as a series of mesodermal outpouchings on the left and right sides of the developing pharynx...

.
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