The hyoid bone Flashcards
The hyoid bone is also known as the…
lingual bone
Origin of the word “hyoid” :
Greek word hyoeides = “shaped like the letter upsilon” (υ)
What is the hyoid bone shaped like?
The hyoid bone is shaped like a horseshoe
The hyoid bone is…
suspended from the tips of the styloid processes
Where is the hyoid bone situated?
Situated between chin & thyroid cartilage
Where does the hyoid bone lie at rest?
At rest- lies at level of C3 behind & base of mandible in front
How is the hyoid bone suspended?
Suspended in position by ligaments & muscles
What does the hyoid bone provide?
Provides attachment to floor of mouth, tongue above, larynx
below, epiglottis & pharynx behind
The hyoid bone is not…
articulated to any other
bone
What is the hyoid bone supported by and what does it support?
Supported by muscles of neck
& in turn supports root of
tongue
Describe the hyoid bone.
The hyoid bone has a U-shaped body, 2
greater, 2 lesser horns and is a very mobile bone
The hyoid bone has a….
large number of muscles
attached to it
Where does the hyoid bone lie?
Lies in the neck just above larynx
(body lies opposite C3
vertebra) & below mandible
List parts of the hyoid bone.
- Lesser horn
- Greater horn
- Body
The body of the hyoid bone has two surfaces and two borders, namely :
Anterior, posterior surfaces; upper, lower borders
The anterior surface of the body has a median ridge. What does the median ridge do?
The median ridge divides the body into two lateral halves
Describe the posterior surface.
The posterior surface is concave
What is the lateral end of the body continuous with?
The lateral end of the is continuous with the greater horn
Describe the greater horn of hyoid bone.
The greater horn of the hyoid bone is flattened from above downwards
How does each cornu[of the greater horn] taper?
Each cornu tapers posteriorly
What does each cornu[of the greater horn] end in?
Each cornu ends in a tubercle
The greater horn has 2 surfaces and 2 borders, namely :
2 surfaces (upper & lower); 2 borders (medial, lateral)
Describe the lesser horn of the hyoid bone.
The lesser horn of the hyoid bone is small conical pieces of bone
The lesser horn projects…
upwards from the junction of the body and the greater horn
What connects the lesser horn to the body?
Fibrous tissue
What does the attachments of the hyoid bone form?
The attachments of the hyoid bone form a base for the tongue
The attachments of the hyoid bone are suspended in position by muscles that connect it to the :
mandible styloid process thryoid cartilage sternum scapula
Name the groups of muscular attachments.
- Oral cavity and pharynx
- Suprahyoid
- Infrahyoid
Groups of Muscular Attachments - Oral cavity and pharynx :
- Middle pharyngeal constrictor
- Hyoglossus
- Genioglossus
Groups of Muscular Attachments - Suprahyoid :
Digastric
Stylohyoid
Geniohyoid
Mylohyoid
Groups of Muscular Attachments - Infrahyoid :
Thyrohyoid
Omohyoid
Sternohyoid
Muscles attached to the hyoid bone from above :
• Mylohyoid • Geniohyoid • Fascia of stylohyoid • Fascia of digastric tendon
Muscles running up to the hyoid bone :
- Sternohyoid *Superior belly of omohyoid
* Thyrohyoid
Name the ligaments attached to the hyoid bone.
- Stylohyoid ligament
- Thyrohyoid membrane
- Lateral thyrohyoid ligament
The stylohyoid ligament runs from the…
apex of styloid
process to lesser horn
The thyrohyoid membrane is attached to the…
upper border
of bone – separated from
posterior surface by
retrohyoid bursa
The lateral thyrohyoid ligament runs from the…
tip of greater
horn to superior horn of
thyroid cartilage
Ossification of the hyoid bone has…
Six centers :
2 for the body
1 for each cornu
Where does the ossification of the hyoid bone commence?
Ossification commences in greater cornua toward end of fetal life, in body shortly afterward, & in lesser cornua during 1st or 2nd year after birth
Why are fractures to the hyoid bone rare?
Fractures to the hyoid bone are quite rare due to
protection of the bone by the mandible and cervical
spine.
What are fractures to hyoid bone associated with?
However, fractures are generally associated with
strangulation (found in approximately 1/3 of all
homicides by strangulation); therefore, fractures of
the hyoid are significant in post-mortem findings.
Why would a fracture[to the hyoid bone] occur?
Fractures can also occur as a result of trauma, with
clinical features of pain on speaking, odynophagia
(painful swallowing) and dyspnea (difficulty
breathing)