Back Muscles (Test I)

Question 1

Teres Major

Answer 1

O- dorsal surface of inferior angle of scapula
I- medial lip of intertubercular groove of humerus
A- adducts and medially rotates the arm
N- lower subscapular nerve (C6 & C7)

Question 2

Teres Minor

Answer 2

O- superior part of lateral border of scapula
I- inferior facet on greater tubercle of humerus
A- laterally rotates arm and helps to hold humeral head in glenoid cavity
N- axillary nerve (C5 & C6)

Question 3

Semispinalis

Answer 3

(Thoracis, Cervicis, & Capitis)
O- transverse processes of C4-T12
I- runs superiomedially to occipital bone and spinous processes in cervical and thoracic regions (spanning 4-6 segments)
A- extend head, extend cervical and thoracic regions, rotate those regions contralaterally, stabilize the vertebrae, and proprioception
N- dorsal rami of segmental spinal nerves

Question 4

Spinalis

Answer 4

(Thoracis, Cervicis, & Capitis)
O- broad tendon from the posterior iliac crest, posterior sacrum, sacroiliac and supraspinous ligaments, and spinous processes of lower lumbar and sacral vertebrae
I- spinous processes of upper thoracic vertebrae to the cranium
A- (bilaterally) extend the head and vertebral column, and provide eccentric control during trunk flexion
(unilaterally) lateral flexion of the trunk
N- dorsal rami of segmental spinal nerves

Question 5

Longissimus

Answer 5

(Thoracis, Cervicis, & Capitis)
O- broad tendon from the posterior iliac crest, posterior sacrum, sacroiliac and supraspinous ligaments, and spinous processes of lower lumbar and sacral vertebrae
I- superior to ribs between the tubercles and angles to transverse processes in thoracic and cervical regions, and to the mastoid process
A- (bilaterally) extend the head and vertebral column, and provide eccentric control during trunk flexion
(unilaterally) lateral flexion of the trunk
N- dorsal rami of segmental spinal nerves

Question 6

Iliocostalis

Answer 6

(Lumborum, Thoracis, & Cervicis)
O- broad tendon from the posterior iliac crest, posterior sacrum, sacroiliac and supraspinous ligaments, and spinous processes of sacral and lumbar vertebrae
I- angles of the lower ribs and the cervical transverse processes
A- (bilaterally) extend the head and vertebral column, and provide eccentric control during trunk flexion
(unilaterally) lateral flexion of the trunk
N- dorsal rami of segmental spinal nerves

Question 7

Mulitfidus

Answer 7

O- transverse processes of T1-T3
articular processses of C4-C7
sacrum
ilium
sacroiliac ligament
aponeurosis of erector spinal
mammillary processes of lumbar vertebrae
I- superiomedially to spinous
processes of superior vertebrae (spanning 2-4 segments)
A- extend head, extend cervical and thoracic regions, rotate those regions contralaterally, stabilize the vertebrae, and proprioception
N-dorsal rami of segmental spinal nerves

Question 8

Rotatores

Answer 8

O- transverse processes of vertebrae (best in throacic region)
I- superiomedially to attach to the junction of the lamina and transverse processes/spinous processes of superior vertebrae (spanning 1-2 segments: brevis = 1 segment, longus = 2 segments)
A- extend head, extend cervical and thoracic regions, rotate those regions contralaterally, stabilize the vertebrae, and proprioception
N- dorsal rami of segmental spinal nerves

Question 9

Interspinales

Answer 9

O- superior sufraces of spinous processes of cervical and lumbar vertebrae
I- inferior surfaces of spinous processes of superior vertebrae
A- aid in extension and rotation of vertebral column
N- dorsal rami of segmental spinal nerves

Question 10

Intertransversarii

Answer 10

O- transverse processes of cervical and lumbar vertebrae
I- adjacent transverse processes
A- (bilaterally) stabilize the vertebral column
(unilaterally) aid in lateral flexion of vertebral column
N- dorsal rami of segmental spinal nerves

Question 11

Levatores Costarum

Answer 11

O- tips of transverse proceses of C7 and T1-T11
I- inferiorlaterally to insert on rib between lateral flexion of veterbral column
A- elevate ribs to assist respiration and assist lateral flexion of vertebral column
N- dorsal rami of C8-T11

Question 12

Rectus Capitis Posterior Minor

Answer 12

O- posterior tubercle of posterior arch of the atlas (C1)

I- medial portion of the inferior nuchal line of the occiput

Question 13

Rectus Capitis Posterior Major

Answer 13

O- spinous process of axis (C2)

I- lateral portion of inferior nuchal line of the occiput

Question 14

Obliquus Capitis Superior

Answer 14

O- transverse process of atlas (C1)

I- occipital bone between the superior and inferior nuchal lines

Question 15

Obliquus Capitis Inferior

Answer 15

O- spinous process of axis (C2)

I-transverse process of C1

Question 16

Splenius Capitis

Answer 16

O- spinous processes of C7-T6 and nuchal ligament
I- lateral 1/3 of superior nuchal line and mastoid process
A- (bilaterally) extend head & neck
(unilaterally) lateral flexion & rotation
N- dorsal rami of segmental spinal nerves

Question 17

Splenius Cervicis

Answer 17

O- spinous proceses of C7-T6 and nuchal ligament
I- transverse processes of C1-C3 or C4
A- A- (bilaterally) extend head & neck
(unilaterally) lateral flexion & rotation
N- dorsal rami of segmental spinal nerves

Question 18

Serratus Posterior Superior

Answer 18

O- spinous processes of C7-T3 and nuchal ligament
I- superior aspect of ribs 2-4
A- elevate ribs
N- ventral rami of intercoastal nerves 9-12 (9-11= intercostal nerves and 12-subcostal nerve)