Back and Neck Muscles Flashcards
Trapezius origin
external occipital protuberance of occipital bone, ligamentum nuchae (C1-C6), spinous
processes of C7 through T12
Trapezius insertion
spine of scapula, acromion process of scapula, lateral 1/3 of clavicle
Trapezius actions
upper fibers: upward rotation of scapula, elevation of scapula
middle fibers: retraction of scapula
lower fibers: upward rotation of scapula, depression of scapula
Trapezius innervation
accessory nerve (Cranial Nerve XI)
Trapezius blood supply
transverse cervical a.
Latissimus dorsi origin
spinous processes of T7 through L5, posterior iliac crest of ilium
Latissimus dorsi insertion
crest of lesser tubercle of humerus, floor of intertubercular groove of humerus
Latissimus dorsi actions
extension of humerus, medial rotation of humerus, adduction of humerus
Latissimus dorsi innervation
thoracodorsal nerve
Latissimus dorsi blood supply
thoracodorsal a.
Levator scapulae origin
transverse processes of Cl through C4
Levator scapulae insertion
superior angle of scapula
Levator scapulae actions
elevation of scapula, downward rotation of scapula
Levator scapulae innervation
dorsal scapular nerve
Levator scapulae blood supply
dorsal scapular a.
Rhomboid major origin
spinous processes of T2 through T5
Rhomboid major insertion
medial (vertebral) border of scapula inferior to base of the spine
Rhomboid major actions
retraction of scapula, elevation of scapula, downward rotation of scapula
Rhomboid major innervation
dorsal scapular nerve
Rhomboid major blood supply
dorsal scapular a.
Rhomboid minor origin
spinous processes of C7 and Tl, lower ligamentum nuchae
Rhomboid minor insertion
medial (vertebral) border at the base of the spine of the scapula
Rhomboid minor actions
retraction of scapula, elevation of scapula, downward rotation of scapula
Rhomboid minor innervation
dorsal scapular nerve
Rhomboid minor blood supply
dorsal scapular a.
Splenius capitis origin
lower half of ligamentum nuchae, spinous processes of C7-T4 vertebrae
Splenius capitis insertion
mastoid process of temporal bone, occipital bone below lateral nuchal line
Splenius capitis actions
extend head and neck, laterally flex head and neck; rotate head to same side
Splenius capitis innervation
dorsal rami of middle cervical spinal nerves
Splenius capitis blood supply
Occipital a.
Splenius cervicis origin
spinous processes of T3-T6 vertebrae
Splenius cervicis insertion
transverse processes of C1-C3 vertebrae (anterior to Levator Scapulae)
Splenius cervicis actions
extend head and neck, laterally flex head and neck; rotate head to same side
Splenius cervicis innervation
dorsal rami of spinal nerves
Spenius cervicis blood supply
Occipital a.
Semispinalis capitis origin
transverse processes of C7-T12 vertebrae
Semispinalis capitis insertion
between superior and inferior nuchal lines of occipital bone
Semispinalis capitis actions
extend head and neck, rotate head and vertebral column contralaterally
Semispinalis capitis innervation
dorsal rami of spinal nerves
Semispinalis capitis blood supply
occipital artery
Erector Spinae Group origin
transverse and spinous processes of T10-L5, sacrum, iliac crest of ilium
Erector Spinae Group insertion
spinous processes of thoracic vertebrae, transverse processes of cervical and thoracic vertebrae, ribs, occipital bone, sometimes temporal bone
Erector Spinae Group Actions
extend vertebral column, lateral flexion of vertebral column, head and neck
Erector Spinae Group Innervation
dorsal rami of spinal nerves C1-S5
Erector Spinae Group Blood supply
deep cervical artery, posterior intercostal arteries, subcostal arteries, lumbar artery
Serratus Posterior Superior origin
spines of C7 -T3, ligamentum nuchae
Serratus Posterior Superior insertion
Ribs 1-4
Serratus Posterior Superior Actions
Draws upper ribs up and back
Serratus Posterior Superior Innervation
ventral rami of T1-T4 nerves (intercostal nerves)
Serratus Posterior Superior Blood supply
posterior intercostal arteries 1-4
Serratus Posterior Inferior origin
spinous processes of T11-L2 (via thoracolumbar fascia)
Serratus Posterior Inferior
Insertion
inferior border of ribs 8-12
Serratus Posterior Inferior
Actions
draws lower ribs down and back
Serratus Posterior Inferior
Innervation
ventral rami of T9-T12 (intercostal nerves)
Serratus Posterior Inferior
Blood supply
lowest posterior intercostal artery, subcostal artery, first two lumbar arteries