Deep Back

Question 1

Differences between deep and superficial muscles

Answer 1

Superficial: innervated by accessory nerve (CN1) and branches of brachial plexus (ventral rami of spinal nerves). Help move limbs. Hypaxial.

Deep: innervated by dorsal rami of spinal nerves. Support and move back. Proprioception. Epaxial.

Question 2

Are ventral or dorsal rami larger and why?

Answer 2

Ventral. They have to innervate more parts of the body.

Question 3

Intermediate back muscles

Answer 3

Third layer of hypaxial muscles. Serratus posterior superior and serrates posterior inferior.

Question 4

Attachments of Serrates Posterior Superior

Answer 4

Proximal: nucal ligament, spinous process of C7-T3
Distal: superior border of ribs 2-4

Question 5

Actions of Serrates Posterior Superior

Answer 5

Elevates ribs

Question 6

Innervation of Serrates Posterior Superior

Answer 6

T2-T5 intercostal nerves (ventral rami)

Question 7

Attachments of Serrates Posterior Inferior

Answer 7

Proximal: spinous process of T11-L2
Distal: inferior borders or ribs 8-12, near their angles

Question 8

Actions of Serrates Posterior Inferior

Answer 8

Depress ribs

Question 9

Innervation of Serrates Posterior Inferior

Answer 9

intercostal nerves & subcostal nerves (ventral rami)

Question 10

Splenius Muscles

Answer 10

Splenius Cervicis - inferior

Splenius Capitis - superior

Question 11

Erector Spinae Group

Answer 11

Most lateral to most medial -

iliocostalis: lumborum, thoracis, and cervicis
longissimus: thoracis, cervicis, and capitis
spinalis: thoracis, cervicis, and capitis. Usually just thoracis, other two may be missing all together.

Question 12

Transversospinalis Group

Answer 12

Most superficial to deepest -
Semispinalis: mostly visible at neck. Thoracic, cervicis, and capitis.
Multifidus: mostly in lumbar
Rotatores: rotation in thorax. Seen on thoracic region.

Question 13

Brevis vs. Longus Rotatores

Answer 13

Brevis: span one intervertebral joint
Longus: span two intervertebral joints

Question 14

Segmental Muscles and Innervations

Answer 14

Interspinales: dorsal rami
Intertransversari: dorsal and ventral rami
Levator costarum: dorsal and ventral rami of C8-T11

Question 15

Muscles of suboccipital triangle

Answer 15

Rectus capitis posterior major + minor, Obliquus captious superior and inferior.

Question 16

Innervation of suboccipital triangle

Answer 16

suboccipital nerve = dorsal rami of C1

Question 17

Suboccipital v. greater occipital nerve

Answer 17

Suboccipital: dorsal rami of C1, mainly motor fibers. Between skull and atlas.
Greater Occipital Nerve: dorsal rami of C2. Mainly sensory fibers. Between atlas and axis.

Question 18

Occipital region nerves and vessels

Answer 18

Vertebral artery, suboccipital nerve, greater occipital nerve, and posterior atlanto-occipital membrane (continuous with ligament flava)

Question 19

Occipital Neuralgia

Answer 19

Irritation of greater occipital and lesser occipital nerve (dorsal and ventral rami of C2). Neck pin that is referred down to jaw. Can be caused by pressure or cold air on back of head.