Lecture 9: Neck Flashcards
Sternocleidomastoid muscle Superior attachment? Inferior attachment? Actions? Innervation?
O: mastoid process
I: sternum and clavicle
A: unilateral: turns face to opposite side (contra lateral) flexes head towards same shoulder (ipsilateral)
Bilateral: flexes the head forward
Innervation: CN 11- spinal accessory nerve
Triangles of the neck
Anterior triangle
Posterior triangle
Anterior triangle: anterior border of SCM, inferior border of mandible slide 6
Posterior triangle:
Posterior boarder if SCM, anterior border of trapezius
Middle 1/3 of clavicle
Label slide 3
Yeep
Anterior triangle of neck Label these regions Submental Submandibular Carotid Slide 7
Do it
What level does the hyoid bone sit
Label the diagram on slide 8
C3 vertebra
Fascias of the neck
Cervical subcutaneous tissue and platysma
View on slide 10
Support viscera and provide slipperiness that allows structures to move and pass over one another, as when you turn your head.
Cervical subcutaneous tissue (most superficial)
Deep cervical fascia:
-investing layer
-pre-tracheal layer
-pre-vertebral layer
Retro pharyngeal space
Describe the investing layer and pre- tracheal layer of deep cervical fascia
Investing layer: surrounds entire neck and encloses “invests” SCM and trapezius. From superior nuchal line to sternum/clavicle/ spine of scapula
Pre-tracheal layer: only anterior neck. Encloses infra-hyoid muscles, thyroid gland, trachea and oesophagus. From hyoid to fibrous pericardium
Label diagram on slide 13 - cadava
Good practice
What does the carotid sheath enclose?
Encloses common and internal carotid arteries, deep cervical lymph nodes, carotid sinus nerve, sympathetic nerve fibres, extends from cranial base to thorax
Label diagram on slide 16- cadava
He
What does the retro pharyngeal space do?
Permits movement of pharynx, oesophagus, larynx and trachea relative t vertebral column during swallowing
What are the structures transversing the superior thoracic aperture?
Trachea Common carotid arteries Subclavian arteries Vagus nerve Recurrent laryngeal nerve Phrenic nerve Sympathetic trunk
Label the diagram of structures in the neck on pg 20
Meh
What are the key blood vessels in the neck?
Subclavian artery
Common carotid artery
External and internal carotid artery
External and internal and anterior jugular veins
What are the key muscles of the neck?
Platysma Sternocleidomastoid Trapezius Supra hyoid Infra hyoid Scalenes and other pre-vertebral muscles
What is platysma innervated by?
Cervical branch of the facial nerve
Cervical plexus
What are the nerves that arise from it and at what level?
Anterior rami C1-C4
-deep to SCM
-anteromedial to levator scapulae and middle scalene
-superficial branches = cutaneous sensory
Deep branches= motor (phrenic nerve, ansa cervicalis)
Cervical plexus nerves:
1. Lesser occipital (C2)
2. Great auricular (C2-C3)
3. Transverse cervical (C2-C3)
4. Supraclavicular (C3 and C4)
What is ansa cervicalis?
Loop of nerves fibres from C1-C3 that provides motor innervation to infra-hyoid muscles (sternohyoid, omohyoid, sternothyroid)
Cervical ganglia of sympathetic trunk
We’re do the superior, middle and inferior levels come out of?
Superior: level C1-C2; large; sends post synaptic sympathetic fibres into cranial cavity and C1-C4 spinal nerves.
Middle: level TP of C6; small; post-synaptic sympathetic fibres to C5-C6 spinal nerves
Inferior: level of TP of C7; star-shaped when fused with first thoracic ganglion; post-synaptic sympathetic fibres to C7-C8 spinal nerves
What is the course of recurrent laryngeal nerves.
Right recurrent laryngeal nerves
Left recurrent laryngeal nerves
Right recurrent laryngeal nerve hooks around right subclavian and heads superiorly to innervate laryngeal muscles.
Left recurrent laryngeal nerve hooks around aortic arch and heads superiorly to innervate laryngeal muscles.
Slide 31
We’re Does the thyroid gland sit in relation to other structures?
Deep to sternothyroid and sternohyoid muscles. Extends C5-T1.
Know how to label the picture on slide 34
Parathyroid glands How many of them are there? We're do they sit? What do they secrete? What is its blood supply? What its nerve innervation is?
Parathyroid glands
How many of them are there? 4
We’re do they sit? Posterior to the thyroid gland
What do they secrete? Parathyroid hormone. Most important hormone for Ca2+ balance.
What is its blood supply? Inferior thyroid artery
What its nerve innervation is? Sympathetic. Cervical ganglia
Slide 36
Larynx. What’s its sensory and motor nerves?
Sensory is internal laryngeal nerve
Motor is recurrent laryngeal nerve
Except the cricothyroid muscle = external laryngeal nerve
What do infrahyoid muscle do?
What do suprahyoid muscles do?
Infra➡ depress hyoid and larynx
Supra➡ elevate hyoid and larynx
Look at the table on slide 46 and know the shit out of it
Important
What is the motor innervation of infra and suprahyoid muscles
Ansa cervicalis supplies:
- sternothyroid
- sternohyoid
- omohyoid
Hypoglossal nerve supplies: intrinsic muscles if tongue
- genioglossu
- hyoglossus
- geniohyoid
- thyrohyoid
- styloglossus
Suprahyoid muscles
Stylohyoid (CN 7) Digastric (CN 7) Mylohyoid (CN V3) Geniohyoid (C1) Raise the hyoid bone (as during swallowing)
Infrahyoid muscles and innervation
Thyrohyoid (C1) - carried by hypoglossal nerve
Sternohyoid (C1-C3) through ansa cervicalis
Omohyoid (C1-C3) through ansa cervicalis
Sternothyroid (C1-C3) through ansa cervicalis
DEPRESS the hyoid bone
