Prevertebral Flashcards
What is the insertion of anterior scalene?
1st rib
What is the origin of anterior scalene?
Anterior tubercles of transverse processes of C3-C6
What innervates anterior scalene?
Cervical spinal nerves C4-C6
What is the action of anterior scalene?
laterally flex neck & elevates 1st rib during forced inspiration
What is the origin of levator scapulae?
Posterior tubercles of transverse processes of C1-C4
What is the insertion of levator scapulae?
Superior part of medial border of scapula
What innervates levator scapulae?
Dorsal scapular nerve C5 and cervical spinal nerves C3 & C4
What are the actions of levator scapulae?
Elevates scapula and tilts glenoid cavity inferiorly
What is the origin of middle scalene?
Posterior tubercles of transverse processes of C4-C7
What is the insertion of middle scalene?
Superior surface of 1st rib; posterior to groove for subclavian artery
What innervates middle scalene?
Anterior rami of cervical spinal nerves
What are the actions of middle scalene?
Laterally flex neck & elevates 1st rib during forced inspiration
What is the origin of posterior scalene?
Posterior tubercles of transverse processes of C4-C6
What is the insertion of posterior scalene?
External border of 2nd rib
What innervates posterior scalene?
Anterior rami of cervical spinal nerves C7 & C8
What is the action of posterior scalene?
Laterally flex neck & elevates 2nd rib during forced inspiration
What is the origin of sternocleidomastoid?
Sternum: anterior surface of manubrium of sternum
Clavicle: superior surface of medial third of clavicle
What is the insertion of sternocleidomastoid?
Lateral surface of mastoid process of temporal bone & lateral half of superior nuchal line
What innervates sternocleidomastoid?
Spinal accessory nerve (CN XI) and C2 & C3 nerves
What are the actions of sternocleidomastoid?
Unilateral contraction: tilts head to same side & contralaterally rotates
Bilateral: 1) extends neck at atlanto-occipital joint; 2) flexes cervical vertebrae so that chin approaches manubrium 3) protrusion
What is the origin of omohyoid?
Superior border of scapula near suprascapular notch
What is the insertion of omohyoid?
Inferior border of hyoid
What innervates omohyoid?
C1-C3 by a branch of ansa cervicalis
What are the actions of omohyoid?
Depresses, retracts & steadies hyoid