Neck, Anterior Cervical Region Flashcards
What are the borders of the Anterior Triangle (Anterior Cervical Region)?
- Midline of neck
- Inferior Border of Mandible
- Anterior Border of SCM
What subdivides the Anterior Cervical Region?
Digastric and omohyoid muscles
What are the subdivisions of the Anterior Cervical Region?
- Muscular Triangle
- Carotid Triangle
- Submandibular Triangle
- Submental Triangle
What are the boundaries of the Muscular Triangle?
- Midline
- Superior Belly of omohyoid
- SCM
What are the boundaries of the Carotid Triangle?
- Superior Belly of omohyoid
- Posterior Belly of digastric
- SCM
What are the boundaries of the Submandibular Triangle?
- Anterior and Posterior Belly of Digastric
- Inferior border of mandible
What are the boundaries of the Submental Triangle?
- Anterior bellies of digastric
- Hyoid bone
is unpaired
What is located in the muscular triangle?
Infrahyoid muscles
Define the Infrahyoid muscles layers in the muscular triangle
- Superficial Layer: Sterohyoid and Omohyoid muscles
- Deep Layer: Sternothyroid and Thyrohyoid muscles
What do the infrahyoid muscles do?
Depress the hyoid bone
What innervates the infrahyoid muscles?
Ansa cervicalis
Thyrohyoid is innervated by n. to thyrohyoid (C1)
What muscles are located in the submandibular triangle?
Suprahyoid muscles
Define the Suprahyoid muscles
- Digastric
- Stylohyoid
- Mylohyoid (attached to the mylohyoid raphe)
What innervates the suprahyoid muscles?
CN V3: Anterior belly of digastric and mylohyoid
CN VII: Posterior belly of digastric and stylohyoid
What is located in the submandibular triangle?
- Submandibular gland
- Facial artery and vein
- Stylohyoid muscle
- Hypoglossal nerve (CN XII)
- Submandibular lymph nodes
What is the submandibular gland surrounded by?
Investing layer of deep cervical fascia
Describe the orientation of the submandibular gland?
Gland wraps around posterior border of mylohyoid
Deep portion and duct will be located in the floor of the mouth
What is located in the carotid triangle?
- Common Carotid Artery (along with internal and external carotid branches)
- Internal Jugular Vein
- Vagus Nerve
- Ansa Cervicalis
- Deep Cervical Lymph Nodes
What is located in the carotid sheath?
- common and internal carotid arteries
- Internal jugular vein
- Vagus Nerve
- Deep cervical lymph nodes
Where do the common carotid arteries branch from?
Right: Brachiocephalic trunk
Left: Aortic arch
What does the external carotid artery supply?
Structures in the neck and face
(Not in the carotid sheath)
What does the carotid sinus do?
Monitors Blood Pressure
What does the carotid body do?
Monitor Oxygen
What innervates the carotid sinus?
Carotid sinus nerve (branch from the CN IX)
When does the common carotid artery bifurcate?
C3
What are the branches of the external carotid artery?
Anterior: Superior thyroid, lingual, and facial aa.
Posterior: Ascending pharyngeal, occipital, and posterior auricular aa.
Terminal: Maxillary and Superficial temporal aa.
Some Anatomists Like Freaking Out Poor Medical Students
Where does the Internal Jugular Vein receive blood from?
Brain
Anterior Face
Cervical Viscera
Deep muscles of neck
Where does the Internal Jugular Vein emerge from the skull?
Jugular Foramen
What sinus is the internal jugular vein a continuation of?
Sigmoid sinus
In comparison to the carotid arteries, where is the internal jugular vein?
In the carotid sheath but lateral to the carotid artery
The internal jugular vein will unite with what veins?
Unities with the subclavian to form brachiocephalic v.
Where is the ansa cervicalis in comparison to the carotid aa.
Anterior to the carotid sheath (not in it)
What levels of the spinal cord is the ansa cervicalis?
C1-C3
The superior root of the ansa cervicalis is from what spinal level?
C1
The inferior root of the ansa cervicalis is from what spinal level?
C2-C3
What does the ansa cervicalis innervate?
Infrahyoid muscles (except Thyrohyoid)
What are the branches of the vagus nerve?
- Superior laryngeal nerve
- Recurrent laryngeal nerves
What are the branches of the superior laryngeal nerve?
Internal laryngeal n. (Sensory)
External laryngeal n. (Motor)
What does the Internal Laryngeal n. travel trhough?
Thyrohyoid membrane
The external laryngeal n. travels with what structure?
Superior thyroid a.
The recurrent laryngeal nn innervate what muscles?
Intrinsic laryngeal muscles
The viscera of the neck is enclosed in what structure?
pretracheal layer of deep cervical fascia
What endocrine output does the thyroid gland produce?
Thyroid hormone (T3/T4 hormones) and Calcitonin
Where is the thyroid gland located (in relation to vertebral levels)?
C5-T1
What are the physical structures of the thyroid gland
2 lobes and an isthmus
Some have a pyramidal lobe
What arteries supply blood to the thyroid gland?
- Superior thyroid artery (from eternal carotid)
- Inferior thyroid artery (from thyrocervical trunk)
- Thyroid ima artery (coming from brachiocephalic trunk and not everyone has this)
The thyroid drains blood from what veins
- Superior thyroid vein (to IJV)
- Middle thyroid vein (to IJV)
- Inferior thryoid vein (To brachiocephalic veins posterior to the manubrium of sternum)
What endocrine function does the parathyroid glands have?
Release parathyroid hormone (PTH)
What are the physical structures of the parathyroid gland?
Superior part
Inferior part
Accessory/aberrant glands common
What happens if you remove the parathyroid glands
Decrease in serum calcium which can cause tetany (involuntary muscle spasms)
What contents are at the root of the neck?
- External and Anterior Jugular Veins
- Prevertebral muscles
- Subclavian artery and vein
- Lymphatics (Deep cervical, thoracic duct, and right lymphatic duct)
- Nerves (Vagus, phrenic, and Sympathetic trunk)
What are the prevertebral muscles?
Longus capitis
Longus colli
Rectus capitis anterior
Rectus capitis lateralis
Scalene muscles
Where are the prevertebral muscles located?
Posterior to retropharyngeal space and surrounded by prevertebral layer of deep cervical fascia
What are the branches of the subclavian artery?
Medial: Vertebral, thyrocervical trunk, and internal thoracic a.
Deep: Costocervical trunk
Lateral: Dorsal scapular a. (variable)
What are the branches of the Thyrocervical trunk?
Suprascapular a.
Transverse cervical a.
Ascending cervical a.
Inferior Thyroid a.
What are the branches of the costocervical trunk?
Deep cervical a.
Superior intercostal a.
The thyroid and parathyroid glands are supplied entirely by branches from the external carotid artery (T/F)
False
Where do the external and anterior jugular veins empty?
Into the subclavian vein in the root of the neck
The IJV and subclavian veins join to form what
Brachiocephalic veins
Where are deep cervical lymph nodes located?
All along the IJV
Where does the deep cervical lymph nodes receive lymph from?
All superficial and deep structures of the head and neck
What forms jugular lymphatic trunks?
Efferent lymphatic vessels
What is the inferior group of deep cervical lymph nodes?
Supraclavicular nodes
What is a Virchow’s node?
Left supraclavicular node (sentinel nodes)
Why is Virchow’s node important?
If this is enlarged, it could mean metastasis from the abdominal cavity
What nerves are found at the root of the neck?
Vagus
Phrenic
Recurrent laryngeal
Sympathetic Trunk
Where does the vagus nerve enter the thorax?
Posterior to brachiocephalic veins
Where does the recurrent laryngeal nerves ascend?
Right: loops under right subclavian a.
Left: loops under aortic arch
*ascends in groove between trachea and esophagus
Where does the phrenic nerves descend?
Anterior surface of anterior scalene muscle before passing posterior to subclavian vein
Where is the sympathetic trunk located?
Posterior to carotid sheath
Define the levels of the Cervical Sympathetic ganglia
Superior: C1-2
Middle: C6
Inferior: C7
Post-synaptic fibers that travel with External and Internal Carotid Arteries are from where?
Superior cervical sympathetic ganglia
The stellate (cervicothoracic) ganglion has nerves from where?
Inferior Cervical Sympathetic ganglia
What nerve would be most likely damaged when the parathyroids are taken out?
Recurrent Laryngeal Nerve