Muscles Flashcards
Trapezius
**Origin: ** descending - external occipital protuberance, ligamentum nuchae, spinous process of C1-C7
transverse - aponeurosis of spinous process of T1-T4
ascending - spinous process of T5-T12
Insertion: descending - lateral 1/3 of clavicle
transverse - medial side of acromion
ascending - upper crest & tubercle of scapular spine
Action: retraction, superior rotation elevation, and depression of scapula
Nerve Supply: spinal accessory, C3-C4
Blood Supply: transverse cervicle artery
latissimus dorsi
Origin: inferior angle of scapula, 9th-12th ribs,
spinous process of T7-T12,
thoracolumbar fascia, posterior 1/3 of iliac crest
Insertion: crest of lesser tuberosity of humerus & intertubercular groove
- *Action: ** extension, adduction, & internal rotation of arms, aids in respiration
- *Nerve Supply:** throacodorsal nerve and posterior cord of brachial plexus (C6-C8)
Blood Supply: thoracodorsal artery
Rhomboideus major
Origin: spinous process of T2-T5
Insertion: medial margin of scapula inferior to spine
Action: stabilization, retraction, elevation, and internal rotation of scapula
Nerve Supply: dorsal scapular nerve (C4-C5)
Blood Supply:
rhomboideus minor
Origin: spinous process of C7-T1
Insertion: medial margin of scapula inferior to spine
Action: stabilization, retraction elevation, and internal rotation of the scapula
Nerve Supply: dorsal scapular nerve (C4-C5)
Blood Supply: dorsal scapular artery
levator scapulae
Origin: spinous process of C1-C4
Insertion: superior angle to medial border of scapula
Action: elevates scapula medially, inclines head ipsilaterally
Nerve Supply: dorsal scapular nerve (C5), C3 & C4 spinal nerves (upper portion of muscle)
Blood Supply: dorsal scapular artery
serratus posterior superior
Origin: spinous process of C7-T-3 & ligamentum nuchae
Insertion: superior margin of 2nd - 5th ribs
Action: elevation of ribs
Nerve Supply: ventral primary rami of spinal nerves T1-T4
Blood Supply: posterior intercostal arteries
serratus posterior inferior
Origin: spinous process of T11-L2, thoracolumbar fascia
Insertion: lateral inferior margins of 8th-12th ribs
Action: lowers ribs
Nerve Supply: ventral primary rami of spinal nerves T9-T12
Blood Supply: posterior intercostal arteries, subscostal artery, lumbar arteries
splenius capitus
Origin: ligamentum nuchae & spinous process of C7-T6
Insertion: mastoid process & lateral end of superior nuchal line
Action: ipsilateral rotation of head, extension & lateral flexion of C-spine & head
Nerve Supply: dorsal prinary rami of C2-C6
Blood Supply: deep cervical artery & posterior intercostal arteries
splenius cervicus
Origin: ligamentum nuchae, spinous process od C7-T6
Insertion: posterior tubercles of transverse process of C1-C3
Action: extension & lateral flexion of head & neck, ipsilateral rotation of head
Nerve Supply: dorsal primary rami of C2-C6
Blood Supply: deep cervical artery & posterior intercostal arteries
what are the erector spinae muscles?
Iliocostalis (lateral)
longissimus (middle)
spinalis (medial)
iliocostlis
**Origin: ** medial 6th - 12th ribs
**Insertion: ** transverse process of C4-C6 & upper angle of 1st-6th ribs
Action: extension, abduction, & rotation of thoracic portion of spine
Nerve Supply: dorsal branches of thoracic nerves
Blood Supply: deep cervical artery, posterior intercostal arteries, subcostal arteries
longissimus
Origin: sacrum, iliac crest, spinous process of lumbar vertebrae, transverse process of lower thoracic vertebrae
Insertion: 2nd-12th ribs, costal processes of lumbar vertebrae, transverse process of thoracic vertebrae
Action: extension & lateral flexion of trunk, neck & head
Nerve Supply: dorsal primary rami of C1-S1
Blood Supply: deep cervical artery, posterior intercostal arteries, subcostal arteries, lumbar arteries
spinalis
Origin: spinous process of inferior T10-L3
Insertion: spinous process of superior T2-T8 & base of skull
Action: support, extension, & lateral flexion of spine
Nerve Supply: dorsal primary rami of thoracic nerve and upper lumbar spinal nerves
Blood Supply: deep cervical artery, posterior intercostal arteries, subcostal arteries, lumbar arteries
deltoid
Origin: lateral 1/3 of clavicle, acromion, & spine of scapula
Insertion: deltoid tuberosity of humerus
Action: abduction of arm, flexion & external rotation (ant. fibers), external rotation & extension (post. fibers)
Nerve Supply: axillary nerve & brachial plexus (C5-C6)
Blood Supply: posterior circumflex humeral artery
supraspinatus
Origin: supraspinatus fossa of scapula
Insertion: greater tubercle of humerus
Action: abduction of arm
Nerve Supply: suprascapular nerve & superior trunk of brachial plexus (C4-C6)
Blood Supply: suprascapularartery
