Triangles Of The Neck And Larynx Flashcards
What are the borders of the anterior triangle?
Midline of neck
SCM
Inferior border of mandible
What are the 4 triangles found within the anterior triangle?
Submental
Submandibular
Carotid
Muscular
What are the borders of the Submandibular Triangle?
Anterior belly of Digastric M.
Posterior belly of digastric m.
Inferior border of mandible
What are the border of the Submental triangle?
Midline of neck
Ant belly of digastric m.
Body of hyoid bone
What are the borders of the muscular triangle?
SCM
Superior belly of omohyoid m.
Body of hyoid bone
What are the borders of the Carotid Triangle?
Posterior belly of digastric m.
SCM
Superior belly of omohyoid m.
What are the borders of the posterior triangle?
What is the floor of this triangle covered by?
SCM
Trapezius m.
Clavicle bone
Prevertebral layer of Deep Fascia
What is the floor of the posterior triangle?
Splenius capitis M .
levator scapulae m.
Scalenes
Semispinalis capitis
What makes the occipital triangle and omoclavicular triangle from the posterior triangle?
Made by the inferior belly of Omohyoid m.
Contents of occipital triangle?
EJV Cervical plexus Spinal accessory n. Brachial plexus trunks Cervicodorsal trunk Cervical lymph nodes
Contents of omoclavicular triangle ?
Subclavian a. And v.
Suprascapular a.
Supraclavicular lymph nodes
Contents of the Posterior triangle?
Thyrocervical trunk
Suprascapular a.
Transverse cervical a.
Costocervical trunk
Deep cervical a. —> paraspinal a.
Supreme intercostal a.
EJV
Subclavian v.
Cervical plexus
Spinal accessory
Phrenic n.
Roots of brachial plexus
Ansa cervicalisWhat muscles are found in the anterior triangle?
What are their actions?
Suprahyoid: elevate hyoid and larynx during swallowing and phonation
Infrahyoid: depress hyoid and larynx
What arteries do you find in the anterior triangle?
Common Carotid A.
Internal and external carotid a.
Contents of submandibular triangle?
Myohyoid
Hyoglossus
Middle and inferior pharyngeal constrictor m.
(Sometimes the parotid gland if it is big enough)
Submandibular gland Submandibular lymph nodes Hypoglossal n. (CN 12) N. To Mylohyoid Facial a. And v.
Contents of carotid triangle?
Thyrohyoid m.
Hyoglossus .
Middle and inferior constrictor Ms. of pharynx
Carotid sheath (with all its contents) Branches of ext. Carotid a.
Internal and external laryngeal ns.
Hypoglossal n.
Spinal accessory n.
Ansa cervicalis
What is in the carotid sheath?
Common and internal carotid a.
Internal jugular v.
Vagus n.
Pharyngeal branch
Superior laryngeal n. (Int. And ext. branch)
Carotid body branch
Deep cervical lymph nodes
Carotid sinus n.
Sympathetic nerve fibersContents of muscular triangle?
Sternothyroid.
Sternohyoid
Thyroid Parathyroid glands Larynx Trachea Esophagus
Common carotid a.
Superior thyroid a.
Inferior thyroid a.
Anterior jugular v.
Thyroid Vs.
Ansa cervicalis
External laryngeal
Recurrent laryngeal
Contents of Submental Triangle?
Mylohyoid M.
Submental lymph nodes
Small veins that unite to form AJV.
What does the superificial branch of transverse cervical a. Run with?
Spinal accessory n.
What does the deep branch of transverse cervical a. Replace?
Replaces dorsal scapular a. To supply levator scapulae and rhomboid Ms.
What is EJV made from?
What does it drain to?
Union of posterior retromandibular v. With posteiror auricular v.
Subclavian v.
When will EJV be visible?
Increased venous pressure due to heart failure or obstruction of superior vena cava
What makes the Brachiocepahlic v.?
Clinical relevance of brachiocephalic v.?
Subclavian v. Joining with IJV
Central line placement done in Brachiocephalic v.
What is Erb’s Point; what does it contain?
Cervical plexus emerges halfway down SCM
Used to a cervical plexus nerve block for anesthesia
What is the most common nerve that is accidentally cut?
Spinal accessory nerve
What does the phrenic n. Supply?
Diaphragm
3, 4,5, keep the diaphragm alive
Where is ansa cervicalis located?
What does it supply?
In fascia of carotid sheath;
Most infrahyoid muscles
What is Torticollis?
Contraction or shortening of SCM that causes the head to tilt toward and the face to turn away from the affected side
Where and what are the carotid sinus and body?
From internal carotid a.
Carotid sinus - baroreceptor used to detect b.p.
Carotid body - chemoreceptors that can monitor O2, ph, etc.
Where does the common carotid a. Bifurcate?
At vertebral levels C3-c4
What are the suprahyoid muscles?
Mylohyoid
Stylohyoid
Digastric
Geniohyoid
What innervates mylohyoid?
N. To mylohyoid
Can be seen branching off from inferior alveolar n.
What innervates stylohyoid?
Facial n.
What innervates the anterior belly of digastric?
What innervates the posterior belly of digastric?
Ant. Belly: n. To Mylohyoid
post. Belly: facial n.
What innervates Geniohyoid?
C1 via hypoglossal n.
What are the infrahyoid Ms. ?
Thyrohyoid
Sternothyroid
Sternohyoid
Omohyoid
What innervates thyrohyoid?
C1 via the hypoglossal n.
What innervates sternothyroid m.?
Ansa cervicalis
What innervates Sternohyoid M.?
Ansa Cervicalis
What innervates omohyoid m.?
Ansa cervicalis
What are the branches of the external carotid a.
Facial Lingual Superior thyroid a. Ascending pharyngeal a. Occipital Posterior auricular Superficial temporal a. Maxillary a.
What are the branches of the superior laryngeal n.?
Internal and external
What does the hypoglossal n. Wrap adjacent to?
Occipital a.
What is the Platysma? What innervates it?
Muscle of facial expression
Cervical branch of facial n.
What is the Thoracic outlet?
Superior thoracic aperture where arteries and nerves emerge
Contents of Thoracic outlet?
Apex of lungs (extend 2 in. Into neck) Subclavian a. And v. Brachial plexus Vagus n. Phrenic n. Thoracic duct Right lymphatic duct Sympathetic chain/trunk Trachea Esophagus
What can result from a stab right above the collarbone?
Stab the lung (extends 2 inches into the neck)- causing a pneumothorax
What happens if you go too deep for a central line placement?
Vein is the most superficial so it is good for central line placement
If you go deeper than that, you puncture the artery
Deeper than the artery you can puncture and collapse the lungs
What is thoracic outlet syndrome?
Compression of brachial plexus on 1st rib
Causes injury to inferior trunk (C8, T1 - injury to hand)
Vasculature issues and ischemia down hand
What is the sole motor supply to diaphragm?
What does this imply if there is spinal cord issue?
Phrenic n.
If spinal cord issues, patient can still breathe bc phrenic nerve is in neck
Where is the sympathetic chain/trunk?
Extends superior to C1 or base of skull
Where are the superior, middle and inferior cervical ganglion of the sympathetic chain located?
Superior: C1-2
Middle: C6
inferior: C7
What is the smallest of the cervical ganglion? And what level is it at?
Middle; C6; at level of cricoid cartilage
May even be absent
What is a Stellate (cervicothoracic) ganglion?
A fused inferior cervical ganglion with a 1st thoracic ganglion
(80% of inferior cervical ganglion present like this)
What are the superficial branches of the cervical plexus for? And what are they?
Sensory Great auricular Lesser occipital Supraclavicular Transverse cervical
What are the deep branches of the cervical plexus for? And what are they?
Motor
Ansa cervicalis
Phrenic n.
Hypoglossal N.
What does the lesser occipital do? and what spinal root is it from?
C2
Skin of neck and scalp posterior to auricle
What does the greater auricular do? and what spinal root is it from?
C2,3
Skin and sheath over parotid gland, mastoid process, auricle, and angle of mandible
What does the transverse cervical do? and what spinal root is it from?
C2,3
Skin of anterior cervical region
What does the supraclavicular n. do? and what spinal root is it from?
C3, 4
Skin over clavicle and over the shoulder
What are the different fascial layers in the neck?
Superficial fascia
Deep cervical fascia
Investing
Pretracheal
Prevertebral
Carotid sheaths
Retropharyngeal spaceWhere is the superficial fascia and what are its contents?
Subcutaneous layer of thin CT layer b/w dermis and investing layer of deep cervical fascia
Cutaneous n. Blood and lymphatic vessels Superficial lymph nodes Fat Platysma m.
Where is the investing layer of deep cervical fascia?
Most superficial; deep to superficial fascia
Surrounds the entire neck
Encloses SCM and Trapezius M.
Parotid and submandibular glands
Why is the investing layer of deep cervical fascia important clinically?
for Mumps
Painful in cheek region due to swelling of parotid and submandibular glands that lie in the investing layer
Where does the investing layer of deep cervical fascia extend to?
Manubrium of sternum, clavicles and acromion and spines of scapula
Where is the Pretracheal layer of deep cervical fascia?
In anterior region of neck, around trachea, thyroid, and esophagus
What does the Pretracheal layer of deep cervical fascia blend with?
Pericardium of heart to mediastinum
What are the three sub layers Pretracheal layer of deep cervical fascia?
Muscular layer
Buccopharyngeal fascia layer
Visceral layer
Where is the Prevertebral Layer of deep cervical fascia?
Encloses vertebral column and associated muscles.
Where does the prevertebral layer of deep cervical layer extend into?
Extends laterally as the axillary sheath into the arm
From cranial base to mediastinum
What does the Carotid sheath blend with?
Blends with prevertebral and Pretracheal layers of deep cervical fascia
What nerve is directly in the Carotid sheath? Not surrounding it
Vagus N.
Where is the Retropharyngeal space?
What is the Retropharyngeal space bound by?
Posterior to pharynx
Bound by buccopharyngeal fascia (anteriorly) Prevertebral fascia (Posteriorly) Carotid sheath (laterally)
Where does the Retropharyngeal Space extend to?
Extends superiorly to base of skull and inferiorly to mediastinum
What is a Retropharyngeal abscess?
Develops secondary to lymphatic drainage or continuous stress of an Upper Repiratory or Oral infections
Causes swelling and difficulty in swallowing and speaking
Can be life threatening
Infection or abscess in the retropharyngeal space could travel toward the mediastinum
What does the facial a. Give rise to?
Ascending palatine a.
Tonsillar a.
Where is the cervical plexus located? (Triangle, muscle, fascia)
Posterior triangle of neck
Halfway up the SCM
prevertebral layer of cervical fascia
Where do the paired spinal nerves leave the spinal cord to give the cervical plexus?
What do they do after they leave?
Paired spinal nerves leave the spinal cord via the intervertebral foramina of the vertebral column
Divide into anterior and posterior nerve fibers
What is the Ansa Cervicalis?
Loop of nerves
C2-3 nerve roots
What innervates Rectus Capitis Anterior and Lateralis?
C1-C2
What innervates Longus Capitis?
C1-C3
What innervates prevertebral muscles?
C2-C3
What does C3-C4 of the cervical plexus innervate?
Levator Scpaulae, Scalenus Medius, (plus middle and anterior scalenus Ms. also receive innervation from cervical plexus
What does Greater Auricular N. Communicate with/
Auricular branch of Vagus N.
Posterior AUricular branch of facial n.
What does the transverse cervical n. Pierce?
Deep cervical fascia
What does the lesser occipital n. Communicate with?
Posterior branch of the greater auricular n.
When and how is a cervical plexus block done?
Used to provide regional anaesthesia for surgery in the neck region
Needle inserted midway up the posterior border of the SCM
Can also affect the phrenic n. So don’t perform on those with co-existing cardiac or respiratory diseases
Where is the thyroid located?
(Triangle and vertebral levels)
Where is the isthmus located?
in muscular triangle
C5-T1
Anterior to 2nd and 3rd tracheal rings
What Arteries supply the thyroid?
Superior thyroid (ant-sup. Aspect of gland)
Inferior thyroid (post-inf. Aspects of gland)
Thyroid ima a.
Clinical importance of thyroid ima a.?
In 10 % of patients, anterior to trachea
Clinically relevant for tracheostomies
Have to perform them below thyroid but must be careful for thyroid ima a. And venous plexus
What forms the Thyroid Plexus of veins?
What do each of them drain into?
Superior, Middle, and Inferior thyroid veins
Superior and middle —> IJV
Inferior —> Brachiocephalic V.
What does the right and left recurrent laryngeal n. Each wrap around?
Right: around subclavian a.
Left: around arch of aorta
Why is the thyroid alble to move?
Ligament bind thyroid gland to trachea and cricoid cartilage of larynx
Allows it to be able to move
If you feel nodule move while swallowing, what does it imply?
It is in the thyroid
NOT in the lymph nodes
What supplies the Parathyroid?
Inferior Thryoid a.
Where is the larynx located (vertebral level)?
C3-C6
What is the function of the larynx?
Phonation and patent airway
Where is the Thyroid cartilage located?
C4
Where is the Cricoid Cartilage located?
C6
What is found going into the Thyrohyoid membrane?
Internal branch of Superior Laryngeal N.
Superior Laryngeal A.
Where do you establish a patent airway during life thretening situations?
thru the Cricothyroid membrane
“Cricothyrotomy”
What innervates Cricothyroid M. ?
Action?
External Laryngeal N.
Does high voice (increase in pitch)
What innervates Thyro-Arytenoid M.?
Action?
Inferior laryngeal N. (From Recurrent Laryngeal n.)
Low pitch
Which intrinsic muscle of the larynx is the only abductor?
Posterior Crico-Arytenoid
What innervates Posterior Cricoartyenoid m?
Action?
Inferior Laryngeal n. (From Recurrent laryngeal n.)
Only abductor
What are the adductors of the larynx?
What are they important during?
Lateral cricoarytenoid
Transverse arytenoid
Oblique arytenoid
Important during phonation
Which intrinsic laryngeal m. Does forced respiration?
Posterior Cricoarytenoid
Which laryngeal msucles are involved with phonation?
Lateral, transverse, and oblique arytenoid
What laryngeal msucles are involved in whispering?
Lateral and oblique arytenoids
What arteries supply the larynx above adn below the vocal folds?
Above: Superior laryngeal a.
Below: inferior laryngeal a.
What nerves innverate the larynx above and below vocal folds?
Sensory Above: internal branch of superior laryngeal n.
Sensory below: inferior laryngeal n.
Motor: Inferior Laryngeal n.
(Except for cricothyroid m. done by external branch of superior laryngeal n.)
What are the lymphatics for above and below the vocal folds?
Above: superior deep cervical
Below: Inferior deep cervical
What is the laryngeal cavity?
What does it communicate with?
What is it continuous with?
From laryngeal inlet to inferior border of cricoid cartilage
Communicates with laryngopharynx thru laryngeal inlet
Continuous w/ trachea
What is the laryngeal vestibule?
Between laryngeal inlet and vestibular folds
What are the false vocal cords?
Vestibular folds
What is the laryngeal ventricle?
Between vestibular and vocal folds
What is the infraglottic cavity?
Between vocal folds and inferior border of the cricoid cartilage
What is the rima glottidis?
Space between vocal folds
Air move between here to cause vibrations (i.e. voice)
What makes up the Conus Elasticus/
Lateral cricothyroid L.
Vocal ligament
What does the right lymphatic duct drain?
Right side of face, neck, chest, upper extr.
What does the thoracic duct drain?
Drains left side of face, neck, chest, upper extremity,
Bilaterally: abdomen, pelvis and perineum, and lower extremity
What do the superficial lymphatic vessels drain? And where do they drain into?
Drain lymph from scalp, face and neck
Drain into superficial ring of lymph nodes at the junction of hte neck and head
What are the deep lymphatic vessels? What do they follow?
What do they converge to form?
From deep cervical lymph nodes
Follow the internal jugular v.
Converge to form the left and right jugular lymphatic trunks
What does the left jugular lymphatic trunk combine with and empty into?
Combines w/ the thoracic duct at root of neck
Empties into the venous system via the left subclavian v.
What does the right jugular lymphatic trunk form and empty into?
Forms the right lymphatic duct
Empties into the venous system via the right subclavian v.
What are the superficial lymph nodes?
What do they drain into?
Lymph nodes arranged in ring shape that receive lymph from scalp, face and neck
Drain into deep lymph nodes
Include:
Mastoid
Occipital —> Superior Cervical L.N.s —> EJV
Pre-Auricular
Parotid
Submental
Submandibular —> Deep Cervical L.N.s—> IJV
What do the superior cervical lymph nodes drain into?
EJV
What do the deep cervical lymph nodes drain into?
IJV
What are the Upper and Lower deep cervical L.N.s?
Upper: Jugulodigastric at C4
Receives lymph form thorax and tonsils
Lower: Juguloomohyoid at C6
What is Waldeyer’s Tonsillar Ring?
Collection of lymphatic tissue surrounding superior pharynx, responses to pathogens tha may be ingested or inhaled
Includes: Lingual Palatine Tubal Pharyngeal tonsils
What is Tonsilitis?
Inflamed palatine tonsils
Could be inflamed due to viral or bacterial infection
Can treat by tonsillectomy
