The Neck Flashcards
Surface anatomy of the neck?
Hyoid bone (C3)
Thyroid cartilage (C4,5)
Cricoid cartilage (C6)
tracheal rings
What divides the triangles of the neck
Sternocleidomastoid muscle (anterior and posterior triangles)
What is unique about SCM? What is N and A?
Sternocleidomastoid: two heads (sternal and clavicular)
N: accessory (CN XI) and VR of C2,3
A: flex head and cervical column; one muscle alone tilts head towards shoulder and rotates face up
boundaries of the posterior triangle; subtriangles?
SCM, trapezius, clavicle
occipital triangle and subclavian triangle are divided by inferior belly of omohyoid
muscles of the posterior triangle? what are they covered by?
- splenius capitus
- levator scapulae
3-5. scalenus posterior, medius, anterior
covered by prevetebral layer of deep fascia
What are the N and A of splenius capitus?
N: DR of cervical nerves
A: draw head backward; one muscle alone (with SCM) draws head to one side
What are the N and A of levator scapulae
N: dorsal scapular nerve (from brachial plexus; VR of C5) and VR of C3,4
A: elevate/retract scapula
What are the N and A of the scalenus muscles?
N: VR of cervical nerves (C4,5,6 specifically for anterior)
A: laterally flex and rotate the cervical column; elevate rib 2 (posterior) and rib 1 (medius and anterior)
What are the nerves in the posterior triangle? What do they innervate?
- accessory (CN XI): SCM and trapezius
- dorsal scapular: levator scapulae
- cutaneous branches of cervical plexus
- phrenic (C3,4,5)
- roots of brachial plexus
What is the course of CN XI through the posterior triangle?
- exits skull via jugular foramen
- runs down and lateral to superior border of SCM either pierces or runs deep to SCM, supplying it
- continues down and lateral to trapezius IN THE INVESTING FASCIA (so superficial), supplying it
Describe the origin and course of the dorsal scapular nerve
branch of brachial plexus from VR of C5
pierces scalenus medius (but does not supply it) and goes deep towards levator scapulae
What holds the phrenic nerve down?
subscapular and transverse cervical arteries (branches of the thyrocervical trunk of the subclavian artery) holds it down onto scalenus anterior
Where does the brachial plexus appear?
its roots appear between scalenus anterior and medius.
What are the cutaneous branches of the cervical plexus? and what skin do they supply
- lesser occipital (C2): neck, scalp behind ear
- great auricular (C2,3): ear, parotid gland skin, chin
- transverse cervical (C2,3): front neck
- supraclavicular (C3,4): sternal angle, rib 2, clavicle, scapula
What are the arteries in the posterior triangle?
- third part of subclavian artery
- thyrocervical trunk (from first part of subclavian) and its branches: transverse cervical, subscapular
Veins of the posterior triangle? describe their course
- external jugular (formed by posterior auricular and post. division of retromandibular vein); parallels great auricular nerve on top of SCM; pierces investing layer of deep fascia to go deeper and empty into subclavian
- subclavian vein (deep to SCM, superficial to anterior scalene and phrenic nerve)
Divisions of the Anterior triangle?
- submental
- digastric
- carotid
- muscular
What is in the submental triangle?
- lymph nodes (submental)
- anterior jugular vein
What is in the digastric triangle?
- submandibular gland
- lymph nodes (submandibular)
- facial artery and vein
- hypoglossal nerve (CN XII)
- mylohyoid nerve