Epaxial Muscles

Question 1

Iliocostalis lumborum

Answer 1

origin: wing of the ilium
insertion: transverse processes of the lumbar vertebrae and the last four or five ribs, cranial end inserts on the ribs

Question 2

Epaxial muscles

Answer 2

divided into 3 parallel longitudinal muscle masses on each side; lateral iliocostalis system, intermediate longissimus system, medial transversospinalis system
function: extensors of the vertebral column; lateral movements of the trunk when contracting on only one side

Question 3

Iliocostalis thoracis

Answer 3

long narrow muscle
origin: 12th rib to transverse process of 7th cervical vertebrae; individual components extend between and overlap the ribs

Question 4

Longissimus thoracis et lumborum

Answer 4

origin: crest and medial surface of the wing of the ilium; by means of aponeurosis from supraspinous ligament and spines of the lumbar/thoracic vertebrae; fibers course craniolaterally; lumbar division inserts on various processes of the lumbar and thoracic vertebrae; thoracic division inserts on the ribs and the seventh cervical vertebrae, just medial to the iliocostalis thoracis

Question 5

Longissimus cervicis

Answer 5

cranial continuation of the longissimus muscle into the neck; 4 fascicles; lie in the angle between the cervical and thoracic vertebrae and insert on the transverse processes of the last few cervical vertebrae

Question 6

Longissimus capitus

Answer 6

distinct muscle medial to the longissimus cervicis and splenius muscles
origin: first 3 thoracic vertebrae to the mastoid part of the temporal bone

Question 7

Semispinalis capitis

Answer 7

member of the cervical portion of the transversospinalis group; deep to the splenius; extends from the thoracic vertebrae to the head; 2 muscles- biventer cervicis/complexus

Question 8

Biventer cervicis

Answer 8

dorsal to the complexus; tendinous insertions; arises from the thoracic vertebrae and inserts on the caudal surface of the skull

Question 9

Complexus

Answer 9

ventral to the biventer and arises from cervical vertebrae; inserts on the nuchal crest

Question 10

Splenius

Answer 10

large muscle, dorsolateral surface of the neck, deep to the rhomboideus capitis and the serratus dorsalis cranialis

Question 11

Nuchal ligament

Answer 11

extends from the tips of the spinous process of the first thoracic vertebra to the broad caudal end of the spine of the axis; laterally compressed, paired, yellow elastic band lying between the medial surfaces of the two semispinalis capitis muscles

Question 12

Supraspinous ligament

Answer 12

continues the nuchal ligament caudally and extends from the spinous process of the first thoracic vertebra to the caudal vertebrae; passes from one spinous process to another

Question 13

Semispinalis thoracis

Answer 13

found just caudal to Semispinalis capitis

Question 14

List Epaxial muscles

Answer 14

Iliocostalis muscles (Iliocostalis lumborum, Iliocostalis thoracis), Longissimus muscles (Longissimus thoracis et lumborum, Longissimus cervis, Longissimus capitis), Splenius muscle, Semispinalis muscles (Semispinalis thoracis, Semispinalis capitis- biventer cervicis and complexus)