Lab 1 - Upper Extremity

Question 1

What are the 3 major superficial back and shoulder muscles?

Answer 1

1. trapezius
2. deltoid
3. latissimus dorsi

Question 2

What are the actions of the trapezius? (2)

Answer 2

1. elevates and retracts the scapula (as in shrugging your shoulders)
2. it also helps rotate the scapula during abduction of the arm

Question 3

What are the actions of the deltoid?

Answer 3

The deltoid has 3 heads which each perform different actions.

1. abducts
2. flexes
3. extends the arm

Question 4

What are the actions of the latissimus dorsi?

Answer 4

1. extend
2. adduct
3. medially rotate the arm at the shoulder joint

Question 5

What are the major actions of the pectoralis major?

Answer 5

adduct the arm and medially rotate it

Question 6

What are the key muscles of the arm (upper extremity)?

Answer 6

1. Biceps brachii

2. Triceps

Question 7

What are the actions of the biceps brachii?

Answer 7

1. it is a flexor of the arm at the shoulder joint
2. It is a strong flexor of the forearm at the elbow joint
3. It is a strong supinator of the forearm

Question 8

What are the actions of the triceps ?

Answer 8

elbow extension

Question 9

What is the origin and insertion of the triceps?

Answer 9

origin: scapula & humerus
insertion: olecranon process of the ulna

Question 10

Which muscles of the forearm make up the anterior compartment? (all arise from the medial epicondyle of the humerus)

Answer 10

1. pronator teres
2. flexor carpi radialis
3. palmaris longus
4. flexor carpi ulnaris
5. flexor digitrum superficialis

Question 11

Which muscles of the forearm make up the posterior compartment? (all arise from the lateral epicondyle of the humerus)

Answer 11

1. extensor carpi radialis longus
2. extensor carpi radialis brevis
3. extensor digitorum
4. extensor digiti minimi
5. extensior carpi ulnaris

Question 12

What bones comprise the pectoral/shoulder girdle?

Answer 12

1. Clavicle

2. scapulae

Question 13

What bones make up the shoulder region?

Answer 13

1. clavicle
2. scapulae
3. proximal humerus

Question 14

What functions does the pectoral girdle serve?

Answer 14

1. attachment of the upper limb to the axial skeleton
2. strut placing the upper limb in a position in which it can move freely
3. transmits forces to the axial skeleton

Question 15

What are the 3 major joints in the upper extremity?

Answer 15

1. glenohumeral joint (shoulder joint)
2. Elbow joint
3. 1st CMC joint (thumb)