Superficial Back, Entire Muscle

Question 1

Trapezius

Answer 1

origin- occipital protuberance, ligamentum nuchae, spinous processes C7-T12
insertion- upper=lateral third of clavicle, middle=spine of scapula, lower=root of spine of scapula
action- upper=elevation of scapula and upward rotation of scapula, middle=retraction of scapula, lower=depression and upward rotation of scapula
nerve supply- spinal accessory nerve
blood supply- transverse cervical artery

Question 2

Rhomboid Minor

Answer 2

origin- spinous processes C7-T1
insertion- root of spine of scapula
action- retraction of scapula and downward rotation of scapula
nerve supply- dorsal scapular nerve
blood supply- dorsal scapular nerve

Question 3

Rhomboid Major

Answer 3

origin- spinous processes T2-T5
insertion- vertebral border of scapula from root of spine to inferior angle
action- retraction and downward rotation of scapula
nerve supply- dorsal scapular nerve
blood supply- dorsal scapular artery

Question 4

Levator Scapulae

Answer 4

origin- transverse processes C1-C4
insertion- vertebral border of scapula from superior angle to root of spine
action- elevation and downward rotation of scapula
nerve supply- dorsal scapular nerve
blood supply- dorsal scapular artery

Question 5

Latissimus Dorsi

Answer 5

origin- thoracolumbar aponeurosis, spinous processes T7-T12, iliac crest, lower ribs
insertion- floor of bicipital groove of humerus
action- extension, internal rotation, adduction of shoulder
nerve supply- thoracodorsal nerve
blood supply- thoracodorsal artery

Question 6

Serratus Posterior Superior

Answer 6

origin- ligamentum nuchae
insertion- superior borders of ribs 2, 3, 4
action- elevates ribs
nerve supply- intercostal nerves T1-T4
blood supply- posterior intercostal arteries

Question 7

Serratus Posterior Inferior

Answer 7

origin- spinous processes of T11-L2
insertion- inferior borders of ribs 9-12
action- depresses ribs
nerve supply- intercostal nerves T9-T12
blood supply- posterior intercostal arteries

Question 8

Iliocostalis

Answer 8

origin- posterior ribs, thoracolumbar aponeurosis, iliac crests, sacrum
insertion- cervical transverse processes, posterior ribs
action- bilaterally: extension of vertebral column, unilaterally: lateral flexion of vertebral column
nerve supply- dorsal rami of spinal nerves
blood supply- posterior intercostal arteries, lumbar arteries

Question 9

Longissimus

Answer 9

origin- lower cervical and thoracic transverse processes, thoracolumbar aponeurosis, iliac crests, sacrum
insertion- mastoid process, cervical and thoracic transverse processes
action- bilaterally: extension of vertebral column, unilaterally: lateral flexion of vertebral column
nerve supply- dorsal rami of spinal nerves
blood supply- posterior intercostal arteries, lumbar arteries

Question 10

Spinalis

Answer 10

origin- ligamentum nuchae, cervical, thoracic, and lumbar spinous processes, sacrum, iliac crests
insertion- occipital bone, C2-4, and most thoracic spinous processes
action- bilaterally: extension of vertebral column, unilaterally: lateral flexion of vertebral column
nerve supply: dorsal rami of spinal nerves
blood supply: posterior intercostal arteries, lumbar arteries