OCB04-2007 Neck Flashcards
What regions bound the neck?
Above by the base of the skull posteriorly and the mandible anteriorly
Below by the clavicles and top of the sternum
What are the 4 main compartments of the neck?
visceral
2 vascular
vertebral
What is the vertebral compartment?
There are 7 cervical vertebrae- they support the head while allowing considerable flexibility
Muscles such as the sternocleidomastoid and trapezius muscle surround the posterior and lateral parts of the neck
What is the visceral compartment?
Comprises of the passageways of the larynx and pharynx, eg: trachae
What is the vascular compartment also known as?
Carotid sheath
What is the vascular compartment?
comprises of tubes of fascia containing the common carotid artery, the internal jugular vein and the vagus nerve
How do cervical vertebrae differ from others?
They contain transverse foramen which is the passageway for vertebral artery
What do the superficial layers of the neck contain?
Cutaneous nerves
Blood and lymphatic vessels
Fat
Platysma
What is the platysma?
A flat, thin muscle that covers the entire anterior half of the neck, from the mandible to the clavicles
What is the main role of the platysma?
Tense the skin, helping to depress the mandible in generating facial expression
What is a sign of paralysis of the platysma as a result of damage to the facial nerve?
Visible droop of skin
What muscles are in the deep fascia of the neck?
Sternocleidomastoid
Trapezius
Where does the sternocleidomastoid attach?
Tot the sternum, clavicle and mastoid process of the temporal bone, and occipital protuberance
What does unilateral contraction of one of the sternocleidomastoid muscles cause?
Causes the skull to state to the opposite side and lateral flexion to the sam side
Eg: shortening the right sternocleidomastoid causes the head to rotate to the left and tilt right
What does bilateral recruitment of the sternocleidomastoid muscles cause?
Hold the head straight
Where did the trapezius muscle attach?
Lateral third of the clavicle and spine of scapula and goes down to C12 and occipital protuberance
What does contraction of the trapezius cause?
Moves the scapula when the spine is fixed
What are post-vertebral muscles?
These are long muscles from the base of the skull which extend to the cervical and mid-thoracic vertebrae
What is the function of post vertebral muscles?
They support the head when its upright, and when relaxed the head falls forward
What are prevertebral muscles?
These are used against gravity and are also involved In lateral flexion
They can move the first rib too
Why is the neck vulnerable to injury?
The vertebrae of the neck do not attach to ribs, thus they offer little protection to the viscera and vasculature
Why is the neck an easy pulse point?
Large vessels that supply the brain and the head are very superficial
How many triangles is the outer surface f the neck divided into?
4 triangles: 2 posterior and 2 anterior
What are the borders of the anterior triangles?
Median vertical line of the neck
Inferior margin of the mandible
Anterior margin of the sternocleidomastoid muscle
What are the borders of the posterior triangle?
Middle one third of the clavicle
Anterior margin of the trapezium
Posterior margin of the sternocleidomastoid muscle
What muscle form the boundary between the anterior and posterior triangles?
Sternocleidomastoid muscles
What are the important structures of the posterior triangle?
Accessory nerve
4 superficial branches of the cervical plexus
External jugular vein
What are the main structures within the anterior triangle?
Muscles that attach to the hyoid bone Carotid arteries Internal jugular vein Vagus nerve Thyroid and parathyroid glands
Where do the arteries of the anterior triangle derive from?
Common carotid artery
Where does the common carotid artery arise from?
The brachiocephalic artery on the right side of the body and directly from the arch of the aorta on the left side
Where does the artery enter the neck?
Within the carotid sheath
Which cranial nerves innervate the neck?
VII-XII
How many cervical spinal nerves are there?
8
What do the posterior branches of the cervical spinal nerves supply?
The extensor muscles of the vertebral column, and supply the skin of the posterior parts of the scalp and neck
Which cervical spinal nerve does not supply the ski of the posterior parts of the scalp and neck?
C1
What do the anterior rami form?
The brachial and cervical plexus
Which nerves make up the cervical plexus?
C1- C4
What does the cervical plexus supply?
Muscles and cutaneous region of the neck
Which nerve is formed from the cervical plexus?
Phrenic nerve
What groups is the cervical plexus divided into?
Superficial and deep groups
What does the superficial cervical plexus supply?
Skin of the anterior and lateral parts of the neck and side of the head
What does the deep cervical plexus supply?
Muscles of the neck
What is the ansa cervicalis?
A loop of nerves that are part of the cervical plexus
They lie superficial to the internal jugular vein in the carotid sheath
What do the branches of the ansa cervicalis innervate?
Sternohyoid
Sternothyroid
Omohyoid
Which nerve innervates the thyrohyoid muscle?
Ventral root of the C1
Which nerves form the brachial plexus?
C5, C6, C7, C8, T1
What is the carotid sheath?
A fibrous connective tissue that surround the vascular compartment of the neck
It is part of the deep cervical fascia of the neck
What are the 4 main structures in the carotid sheath?
Common carotid artery
Internal jugular vein
Vagus nerve
Deep cervical lymph nodes
What is the positioning of the carotid artery, internal jugular vein and vagus nerve?
Carotid artery lies medial to the internal jugular vein and the vagus nerve is situated posteriorly between the two vessels
What nerves are in the upper part of the carotid sheath?
Glossopharyngeal
Accessory
Hypoglossal
Where do all the lymph vessels in the neck and head drain?
Deep cervical lymph nodes
