Bones, Muscles, and Nerves of the Trunk

Question 1

Name the sections of the vertebral column with the number of vertebra in each.

Answer 1

Cervical - 7
Thoracic - 12
Lumbar - 5
Sacrum
Coccyx

Question 2

Name the three portions to the sternum superior to inferior.

Answer 2

Manubrium
Body
Xiphoid process

Question 3

How many pairs of true ribs?

Answer 3

7 pairs

Question 4

How many pairs of false ribs?

Answer 4

5 pairs

Question 5

What connects the false ribs to the sternum?

Answer 5

Costal cartilage

Question 6

Name three muscles of the erector spinae.

Answer 6

Spinalis
Longissimus
Iliocostalis

Question 7

Name the action and nerve of the erector spinae.

Answer 7

Action: extends head; extends and laterally flexes vertebral column
Nerve: dorsal primary divisions of spinal nerve

Question 8

Name the action and nerve of the quadratus lumborum

Answer 8

Action: contractions of both muscles extend lumbar portion of vertebral column; contraction of one muscle flexes vertebral column laterally
Nerve: 12th thoracic and upper 4 lumbar spinal nerves (T12-L4)

Question 9

Name the action and nerve of the transverse abdominis

Answer 9

Action: compresses the abdomen
Nerve: intercostal nerves

Question 10

Name the action and nerve of the rectus abdominis

Answer 10

Action: flexes vertebral column, compresses abdomen - aids in bearing down
Nerve: intercostal nerves

Question 11

Name the action and nerve of the internal oblique

Answer 11

Action: contraction of both internal obliques compresses abdomen and flexes vertebral column; contraction of one bends vertebral column laterally and rotates it
Nerve: intercostal nerves

Question 12

Name the action and nerve of the external oblique

Answer 12

Action: contraction of both compresses abdomen and flexes vertebral column; contraction of one will bed vertebral column laterally and rotate it
Nerve: intercostal nerves

Question 13

Name the action and nerve of the external intercostals

Answer 13

Action: contraction elevates the ribs - creating space of inhalation; relaxation depresses the ribs - assisting exhalation
Nerve: intercostal nerves

Question 14

Name the action and nerve of the internal intercostals

Answer 14

Action: contraction draws adjacent nerves together during forced exhalation
Nerve: intercostal nerves

Question 15

Name the action and nerve of the diaphragm

Answer 15

Action: contraction causes it to flatten and increases vertical dimension of the thoracic cavity to inhale; relaxation causes it to move superiorly and decreases vertical dimension of the thoracic cavity to exhale
Nerve: phrenic nerve

Question 16

Name the action and nerve of the rhomboid major and minor

Answer 16

Action: elevates and adducts scapula and rotates it downward (glenoid fossa is downward); stabalizes scapula
Nerve: dorsal scapular nerve

Question 17

Name the action and nerve of the trapezuis

Answer 17

Action: superior fibers elevate scapula; middle fibers adduct scapula; inferior fibers depress and upwardly rotate scapula
Nerve: spinal accessory nerve

Question 18

Name the action and nerve of the serratus anterior

Answer 18

Action: abducts scapula and rotates it upward, elevates ribs when scapula is fixed
Nerve: long (Bell’s) thoracic nerve
Plank push up to strengthen

Question 19

Name the action and nerve of the pectoralis minor

Answer 19

Action: abducts scapula and rotates it downward, elevates 3-5th ribs during forced inhalation when scapula is fixed
Nerve: medial pectoral nerve