UNIT 1: shoulder muscles

Question 1

Which muscles pass from trunk to humerus bypassing the scapula?

Answer 1

• pectoralis major

- latissimus dorsi

Question 2

PECTORALIS MAJOR:

1) Where does it arise from?
2) Where does it insert?
3) What movement does it produce?

Answer 2

1) medial third of clavicle, sternum, 1st 6 front costocartilages
2) anterior edge of bicipital groove
3) adductor/ internal rotation

Question 3

LATISSIMUS DORSI:

1) Where does it insert?
2) What movements does it produce?

Answer 3

1) posterior edge of bicipital groove

2) powerful adductor/ depressor of scapula

Question 4

DELTOID:

1) Where does it arise from?
2) Where does it insert?
3) What movements does it produce?

Answer 4

1) spine of scapula, acromion and lateral third of clavicle
2) deltoid tuberosity
3) anterior=flexor, lateral= abductor, posterior = extensor

Question 5

which muscles hold the scapula in place and allow it to move in relation to trunk?

Answer 5

• serratus anterior
• levatus scapulae
• rhomboids
• trapezius
• pectoralis minor

Question 6

SERRATUS ANTERIOR

1) Where does it insert?
2) What movements does it produce?

Answer 6

1) medial border of scapula

2) protusion (pull scapula around ribcage)/ upward and downward rotation when upper/lower fibres contract separately

Question 7

LEVATOR SCAPULAE

1) Where does it insert?
2) What movements does it produce?

Answer 7

1) upper medial border of scapula

2) elevation of scapula

Question 8

RHOMBOIDS

1) Where does it insert?
2) What movements does it produce?

Answer 8

1) medial border of scapula

2) elevates/retracts scapula

Question 9

TRAPEZIUS

1) What muscles does it overly?
2) where does it insert?
3) What movements does it produce?

Answer 9

1) rhomboids/ levator scapulae/ serratus anterior
2) Upper/lower part converge onto spine of scapula
3) elevation of scapula

Question 10

PECTORALIS MINOR

1) Where does it arise from?
2) Where does it insert?
3) What movement does it produce?

Answer 10

1) arises between 2nd and 4th ribs
2) inserts onto coracoid process
3) depression of scapula

Question 11

SUBCLAVIUS

1) origin/insertion?
2) what movement does it produce?

Answer 11

1) from 1st rib to clavicle

2) anchors/depresses clavicle

Question 12

OMOHYOID

1) Where does it insert?
2) what movement does it produce?

Answer 12

1) upper edge of spine of scapula

2) depresses hyoid bone/larynx

Question 13

what two divisions are axio-appendicular muscles split into and what are their roles?

Answer 13

• anterior: move pectoral girdle

- posterior: attach superior appendicular skeleton of upper limb to axial skeleton

Question 14

which four muscles form anterior axio-appendicular muscles?

Answer 14

• pectoralis major
• pectoralis minor
• subclavius
• serratus anterior

Question 15

how are the posterior axio-appendicular further subdivided?

Answer 15

• intrinsic shoulder = scapulohumeral muscles

- extrinsic shoulder = superficial (trapezius/latissimus dorsi) and deep (levator scapulae/rhomboids)

Question 16

which muscles/bones form the clavipectoral triangle?

Answer 16

superior border: middle 1/3 of clavicle
medial border of deltoid
lateral border of pectoralis major

Question 17

what is contained in the clavipectoral triangle?

Answer 17

cephalic vein