A10 - Neck Flashcards
What are the boundaries of the submandibular triangle?
Superior: lower border of mandible
Antero-inferiorly: Anterior belly of digastric
Postero-inferiorly: Posterior belly of digastric
What are the contents of the submandibular triangle?
Submental lymph nodes
What are the boundaries of the submental triangle?
Inferior: hyoid bone
Medial: midline of neck
Lateral: anterior belly of digastric
What are the contents of the submental triangle?
Submental lymph nodes, submental glands, hypoglossal nerve,
What are the contents of the submental triangle?
Submandibular lymph nodes, submandibular glands, hypoglossal nerve, mylohyoid nerve, facial artery, facial nerve
What are the boundaries of the carotid triangle?
Superior: posterior belly of digastric
Lateral: anterior part of sternocleidomastoid
Inferior: superior part of omohyoid
What are the contents of the carotid triangle?
Carotid sheath, containing the common carotid artery, internal jugular vein, vagus nerve
Deep cervical lymph nodes
Larynx
Hypoglossal nerve
What are the boundaries of the muscular triangle?
Medial: midline of neck
Superior: hyoid bone
Supero-lateral: superior part of omohyoid
Infero-lateral: inferior part of SCM
What are the contents of the muscular triangle?
Infrahyoid muscles: sternohyoid, omohyoid, thyrohyoid, sternothyroid
Thyoid and parathyroid glands
Pharynx
What are the boundaries of the occipital triangle?
Anterior: posterior part of SCM
Posterior: anterior part of trapezius
Inferior: inferior part of omohyoid
What are the contents of the occipital triangle?
Spinal part of cranial nerve XI (accessory)
Branches of cervical plexus
Scalene muscles
Occipital lymph nodes
What are the boundaries of the subclavian triangle?
Inferior: lateral 1/3 of clavicle
Superior: inferior part of omohyoid
Anterior: posterior part of SCM
What are the contents of the subclavian triangle?
Suprascapular nerve
3rd part of subclavian artery
External jugular vein
Roots and trunks of brachial plexus
Supraclavicular lymph nodes
What is the location of superficial cervical fascia and what it consists of?
Lies between the dermis and deep cervical fascia. Consists of loose connective tissue, has a thin sheet of muscle (platysma) = innervated by cervical branch of facial nerve
What are the layers of the deep cervical fascia?
Investing
Prevertebral
Pretracheal
Carotid sheath
Where is the investing fascia located?
Surrounds all structures in the neck, i.e. SCM, trapezius, infrahyoid muscles, and the submandibular and parotid glands
Where is the prevertebral layer of fascia located?
Surrounds the vertebrae and deep cervical muscles of the neck (scalenes, prevertebral muscles, muscles of back) and the brachial plexus and subclavian artery (forms the ‘axillary sheath’)
Where is the pretracheal layer of fascia located?
Surrounds the trachea, oesophagus and thyroid gland. It fuses with the pericardium. 2 parts:
- Muscular part= encloses infrahyoid muscles
- Visceral part= encloses trachea, thyroid gland and oesophagus
Where is the carotid sheath located?
Surrounds the common carotid artery, internal carotid artery, internal jugular vein, vagus nerve
Formed by contributions of the other 3 layers
What are the 3 layers of viscera and where do they surround?
1: Endocrine: thyroid and parathyroid
2: Respiratory: trachea and larynx
3: Alimentary: pharynx and oesophagus
What layer is continuous with fascia of the pharynx?
Pretracheal layer - fuses with buccopharyngeal fascia posteriorly
Where do the common carotids branch from?
L common carotid: branches from the arch of aorta
R common carotid: branches from the brachiocephalic trunk (along with R subclavian)
What do the internal carotid arteries supply?
Brain, eyes and scalp
Where does the common carotid bifurcate?
Carotid triangle
What are the branches of the external carotid artery? Specify whether they’re anterior, medial, posterior or terminal
Superior thyroid - anterior
Ascending Pharyngeal - medial
Lingual - anterior
Facial - anterior
Occipital - posterior
Posterior auricular - posterior
Superficial temporal - terminal
Maxillary - terminal
Which arteries supply deep vs superficial structures of the face?
Deep = maxillary
Superficial = facial and superficial temporal
Where does the ECA terminate?
In the parotid gland
What arteries supplies blood to the scalp? Where are they derived?
Supratrochlear - ICA
Supraorbital - ICA
Superficial temporal - ECA
Occipital - ECA
Posterior auricular - ECA
What drains the brain and meninges?
Dural venous sinuses
What drains the scalp and face?
Veins synonymous with arteries, which then empty into internal jugular and external jugular veins
What drains the neck?
Anterior jugular vein
What is the external jugular vein formed from? Where does it drain into?
Union of retromandibular and posterior auricular veins
Drains into subclavian vein
What is the internal jugular vein formed from? Where does it drain into?
Continuation of sigmoid sinus
Forms the braciocephalic with the subclavian vein
What structures do the superficial cervical vessels drain? Where do they drain into?
Scalp, face and neck
Drains into superficial lymph nodes
Where do deep cervical vessels arise? What do they converge to form?
From deep cervical lymph nodes
Converge to form the R and L jugular lymphatic trunks:
- L jugular trunk - combines with thoracic duct and drains into L subclavian
- R jugular trunk - drains into R subclavian
What are the main superficial lymph nodes?
Mastoid - posterior to ear
Occipital - back of head
Superficial cervical - course of EJV
Pre-auricular - in front of ear
Parotid - superficial to parotid glands
Submandibular - in submandibular triangle
Submental - between anterior bellies of digastric
What 2 folds are formed by the aryepiglottic membrane?
Free upper border forms the aryepiglottic fold
Lower fold forms the false vocal cords (vestibular fold)
What forms the true vocal cords?
Cricothyroid membrane - free upper fold
What is the role of the cricothyroid muscle?
Increases the length of the vocal cords, so raises pitch of voice
What innervates the cricothyroid muscle?
External branch of superficial laryngeal nerve
What is the role of the posterior cricoarytenoids and what innervates them?
Abducts / opens the vocal cords
Recurrent laryngeal nerve
What is the role of the interarytenoids and what innervates them?
Adduct/ close the vocal cords
Recurrent laryngeal nerve
What is the role of the aryepiglottic muscle and what innervates it?
Narrows the laryngeal inlet
Recurrent laryngeal nerve
What do the superior articular facets of C1 articulate with? What movement does this joint allow?
Occipital condyles
Flexion, extension, lateral flexion
What does the dens of C2 articulate with and what strengthens this joint?
Anterior arch and lateral masses of C1
Strengthened by apical, alar and cruciate ligaments
What do the transverse foramina of cervical vertebrae transmit?
Vertebral artery and vein
(C7 only transmits the vertebral vein)
What innervates the infrahyoid muscles?
All apart from thyrohyoid are innervated by ansa cervicalis
Thyrohyoid = hypoglossal nerve
What are the attachments of omohyoid?
Scapula (superior border) to body of hyoid bone
The muscle is attached by an intermediate tendon in the middle to split it into superior and inferior omohyoid
What are the attachments of the digastric muscle?
Anterior belly: digastric fossa (under chin) to hyoid bone
Posterior belly: mastoid process to hyoid bone
Joined by an intermediate tendon
What are the attachments of the trapezius?
O: nuchal line of occipital bone
I: scapula and lateral 1/3 of clavicle
What vertebral level is the hyoid bone?
C3
What vertebral level is the cricoid cartilage?
C6
What vertebral level is the upper edge of the thyroid cartilage?
C4
What vertebral level is the thyroid gland (isthmus)?
C7
What vertebral level is the suprasternal notch?
T2/T3
What does contraction of the infrahyoid muscles lead to?
depresses the hyoid bone
What does contraction of the suprahyoid muscles lead to?
Depresses the mandible, however if the mandible is fixed then it elevates the thyroid
List the suprahyoid muscles
Anterior and posterior belly of digastric
Mylohyoid
Stylohyoid
Geniohyoid
List the infrahyoid muscles
Superior and inferior belly of omohyoid
Sternothyroid
Thyrohyoid
Sternohyoid
What is the attachment of the sterocleidomastoid?
Sternal head: manubrium
Clavicular head: medial 1/3 of clavicle
Both heads insert onto mastoid process (of temporal bone) and superior nuchal line of occipital bone
