16.5 Anatomy: Muscles of the upper limb

Question 1

What does the pectoral girdle allow?

Answer 1

Scapula to move on thoracic wall

Question 2

What are the extensions/processes of the scapula?

Answer 2

Posterior: acromion
Anterior: Coracoid process

Question 3

What are the muscles that attach the pectoral girdle to the trunk from the thoracic wall? (4)

Answer 3

Pectoralis Major
Pectoralis Minor
Subclavius
Serratus Anterior

Question 4

What are the muscles that attach the pectoral girdle to the trunk from the vertebral column? (5)

Answer 4

Trapezius
Latissimus Dorsi
Levator Scapulae
Rhomboid Major
Rhomboid Minor

Question 5

What stabilises the clavicle?

What stabilises the scapula?

Answer 5

Subclavius

Pectoralis minor

Question 6

What does Pec major do? (3)

Answer 6

Adductor and medial rotator, also an accessory muscle of inspiration

Question 7

What underlies pec major?

Answer 7

Subclavius, pec minor

Question 8

What is serratus anterior also called? What does it do?

What happens if the nerve supply is damaged?

Answer 8

Boxer’s muscle

Keeps scapula against chest wall during protraction

Winged scapula can occur

Question 9

What are the muscles attaching the humerus to the scapula?

Which ones are the rotator cuff muscles? (4)

Answer 9

Deltoid
Subscapularis*
Supraspinatus*
Infraspinatus*
Teres minor*
Teres major

Question 10

What inserts onto the superior, middle and inferior facet of the greater tubercle of the humerus?

Answer 10

Superior: Supraspinatus
Middle: Infraspinatus
Inferior: Teres minor

Question 11

What converges onto the lesser tubercle of the humerus?

Answer 11

Subscapularis

Question 12

What are the muscles of the anterior compartment of the arm? What do they do?

Answer 12

Coracobrahialis
Biceps
Brachialis

(flexors)

Question 13

What are the muscles of the posterior compartment of the arm? What do they do?

Answer 13

Tricepts

Extensors

Question 14

What does teres major do?

Answer 14

Adductor and medial rotator

Question 15

Where do the short and long head of biceps originate from?

Answer 15

Short head: corocoid process

Long head: supraglenoid tubercle (scapula)
-Intracapsular, extrasynovial

Question 16

Where does biceps insert?

Answer 16

Crosses elbow joint, inserts into radial tuberosity (tendinous attachment)

Question 17

What are the superficial and deep muscles of the arm?

Answer 17

Superficial: biceps, triceps
Deep: coracobrachialis/brachialis, triceps (deep)

Question 18

Where does the coracobrachialis insert? What pierces it?

Answer 18

Midshaft of humerus

Musculocutaneous nerve pierces it

Question 19

What is the ‘rule’ for superficial and deep muscles?

Answer 19

Superficial: proximal origin, inserting distally

Deep: arise from shaft of long bone that they overlie

Question 20

What does coracobrachialis do?

What does brachialis do?

Answer 20

Weak action on shoulder joint (flexion, adduction)

Flexes forearm/elbow

Question 21

What does biceps do?

Answer 21

Flexes arm, but supinator when elbow is mid prone

Question 22

What are the heads of the triceps? Where do they attach?

Answer 22

Superficial: long (scapula), lateral (humerus)

Deep: medial (shaft, humerus)

Question 23

Where does triceps insert?

Answer 23

Olecranon process of the ulna

Question 24

Where is the common flexor origin?

What group of muscles arise from there?

Answer 24

Medial epicondyle of the humerus

Superficial muscles of the forearm

Question 25

What are the superficial muscles of the forearm? (5) Which ones have 2 heads?

Answer 25

``` Pronator teres* Flexor carpi radialis Palmaris longus Flexor digitorum superficialis* Flexor carpi ulnaris* ```

Question 26

Where do superficial muscles of the forearm insert?

Answer 26

Pronator teres inserts onto lateral aspect of radius Other four reach wrist

Question 27

Which muscle is often considered the intermediate muscle?

Answer 27

FDS (bulk of anterior compartment of forearm)

Question 28

Where do FCR and FCU insert?

Answer 28

FCR: base of 2nd/3rd MC FCU: Pisiform (ligament extends into base of 5th MC)

Question 29

Where do each of the 2 heads in the superficial muscles of the forearm originate from?

Answer 29

PT: CFO and ulna head (median nerve between) FDS: extensive proximal attachment to all bones (median nerve under fibrous arch) FCU: CFO, proximal ulna