Week 23 - Anterior Neck Flashcards
How many cervical vertebrae form the cervical region of the vertebral column?
Seven cervical vertebrae
What do the stacked vertebral bodies of the cervical vertebrae support?
The head
What type of joints provide flexibility for head positioning in the cervical region?
Craniovertebral joints
What are the characteristics of typical cervical vertebrae (3rd–6th)?
- Small vertebral body
- Longer from side to side than anteroposteriorly
- Superior surface is concave
- Inferior surface is convex
- Large and triangular vertebral foramen
- Transverse processes include foramina transversaria
- Superior facets directed superoposteriorly
- Inferior facets directed inferoposteriorly
- Short spinous processes, bifid in individuals of European heritage
What is unique about the C1 vertebra (atlas)?
It is a ring-like, kidney-shaped bone lacking a spinous process or body
What does the C2 vertebra (axis) feature that is notable?
A peg-like dens (odontoid process) projecting superiorly from its body
What is the vertebra prominens and why is it named so?
C7, named for its long spinous process, which is not bifid
Where does the hyoid bone lie in the neck?
At the level of the C3–C4 vertebrae
What is the shape of the hyoid bone and its significance?
U-shaped, derived from the Greek word hyoeidçs, meaning ‘shaped like the letter upsilon’
How is the hyoid bone suspended?
By muscles connecting it to the:
- mandible
- styloid processes
- thyroid cartilage
- manubrium of the sternum
- scapulae
What are the main components of the hyoid bone?
- Body
- Greater horns
- Lesser horns
What is the approximate width and thickness of the body of the hyoid?
Approximately 2.5 cm wide and 1 cm thick
What is the function of the hyoid bone?
Serves as an attachment for anterior neck muscles and a prop to keep the airway open
What connects the greater horns to the body of the hyoid in young people?
Fibrocartilage
What may happen to the greater horns of the hyoid in older people?
They are usually united by bone
What is the lesser horn of the hyoid and how is it connected?
A small bony projection connected to the body by fibrous tissue and sometimes to the greater horn by a synovial joint
True or False: The hyoid bone articulates with other bones.
False
What is the carotid sheath?
A tubular fascial investment that extends from the cranial base to the root of the neck
What layers of fascia does the carotid sheath blend with anteriorly?
The investing and pretracheal layers of fascia
What layer of fascia does the carotid sheath blend with posteriorly?
The prevertebral layer of fascia
What structures are contained within the carotid sheath? List them.
- Common carotid artery
- Internal carotid artery
- Internal jugular vein
- Vagus nerve (CN X)
- Some deep cervical lymph nodes
- Carotid sinus nerve
- Sympathetic nerve fibers (carotid peri-arterial plexuses)
Where does the carotid sheath extend to superiorly?
The cranial base (basiocciput)
Where does the carotid sheath communicate inferiorly?
With the mediastinum of the thorax
True or False: The carotid sheath represents potential pathways for the spread of infection and extravasated blood.
True