KIN 100 - Axio-Appendicular Muscles (lecture 5)

Question 1

2 groups of muscles in the upper limb

Answer 1

1. Anterior axio-appendicular muscles
2. Posterior axio-appendicular muscles

Question 2

What are the 4 Anterior Axio-Appendicular Muscles

Answer 2

1. Pectoralis major
2. Pectoralis minor
3. Subclavius
4. Serratus Anterior

Question 3

What are the 4 Posterior Axio-Appendicular Muscles

Answer 3

1. Trapezius
2. Latissiumus dorsi
3. Levator scapula
4. Rhomboid major and minor

Question 4

Pectoralis major

Answer 4

proximal attachment: sternum and medial clavicle

distal attachment: lateral lip of bicipital groove

Innervation: lateral and medial pectoral nerves

actions: Flex, extend and adduct shoulders, medially rotates

Question 5

Pectoralis minor location

Answer 5

deep to pectoralis major

Question 6

Pectoralis minor

Answer 6

Proximal attachment: ribs 3, 4, 5

Distal attachment: coracoid process

Innervation: medial pectoral nerves

Actions: assists during respiration, stabilizes scapula to ribcage

Question 7

Commonalities between pectoralis major and minor

Answer 7

same nerve innervation: medial pectoral nerve

“MMM rule” - medial pectoral nerve supplies the major and minor pecs

Question 8

Does the pectoralis minor help with arm movement

Answer 8

no, pec minor has not attachments to the humerus

Question 9

Subclavius

Answer 9

proximal attachment: rib 1 and 1st costal cartilage

distal attachment: inferior clavicle (subclavian groove)

Innervation: subclavian nerve

Action: anchors and depresses clavicle

Question 10

Serratus Anterior

Answer 10

proximal attachment: lateral surface of ribs 1-8 (“serr-8-us”)

distal attachment: medial border of scapula

Innervation: long thoracic nerve

Action: protracts scapula

Question 11

Trapezius

Answer 11

Proximal attachment: base of skull, nuchal ligament, spinous processes of thoracic vertebrae

Distal attachment: lateral clavicle, acromion, spine of scapula

Innervation: Accessory nerve

Action: Depress, elevates, retracts scapula, rotates glenoid cavity upwards

Question 12

Latissimus dorsi

Answer 12

Proximal attachment: Spinous processes of inferior 6 thoracic vertebrae, thoracolumbar fascia, Iliac crest

Distal attachment: floor of bicipital groove

Innervation: thoracordorsal nerve

Action: Shoulder extension, adduction, medially rotates

Question 13

What muscle shares the same actions as latissimus dorsi?

Answer 13

Pectoralis major (shoulder extension, adduction, internal/medial rotation)

Question 14

levator scapula

Answer 14

proximal attachment: transverse processes of cervical vertebrae

distal attachment: superior angle of scapula, medial border of scapular superior to root of spine

Innervation: dorsal scapular nerve

Action: elevates scapula
rotates glenoid fossa inferiorly

Question 15

Rhomboid major

Answer 15

proximal attachment: spinous processes of T2-T5

Distal attachment: at the medial border of scapula inferior to the spine

Innervation: dorsal scapular nerve

Action: retracts scapula, rotates glenoid fossa inferiorly

Question 16

Rhomboid minor

Answer 16

proximal attachment: spinous processes of C7 and T1

Distal attachment: medial border of scapula at the spine

Innervation: dorsal scapular nerve

Action: retracts scapula, rotates glenoid fossa inferiorly

Question 17

What muscles are responsible for the medial/inferior rotation of the shoulder

Answer 17

Latissimus dorsi and pectoralis major

Question 18

What muscle is responsible for the upward rotation of the glenoid cavity

Answer 18

trapezius

Question 19

What muscles are responsible for the down/inferior rotation of the glenoid cavity

Answer 19

levator scapula and rhomboid major/minor