Week 8

Question 1

What bones form the elbow joint?

Answer 1

Humerus, radius, and ulna.

Question 2

What type of joint is the elbow?

Answer 2

Synovial hinge joint.

Question 3

What is the normal range of motion at the elbow?

Answer 3

0° extension to 150° flexion.

Question 4

What is the carrying angle and who typically has a greater one?

Answer 4

5–15° (cubitus valgus); typically greater in women.
- ensures that our arms don’t hit our hips as we are walking, that is why it is typically larger for women, because we have wider hips.

Question 5

What are the main ligaments stabilizing the elbow joint and what are their functions?

Answer 5

• ulnar (medial) collateral ligament: provides stability against inner pressures placed on the elbow and throwing motions.
• radial (lateral) collateral ligament: provides stability against outer pressures placed on the elbow.
• annular ligaments: Encircles the radial head to allow for smooth rotation of the radioulnar joint.

Question 6

What is the cubital fossa?

Answer 6

A transition zone at the anterior elbow containing the median nerve and brachial artery.

Question 7

What are the three main elbow flexors?

Answer 7

Biceps brachii, brachialis, and brachioradialis.

Question 8

What nerve innervates the biceps and brachialis?

Answer 8

Musculocutaneous nerve.

Question 9

What nerve innervates the brachioradialis?

Answer 9

Radial nerve.

Question 10

What is the primary elbow extensor and what nerve innervates it?

Answer 10

Triceps brachii (innervated by radial nerve).

Question 11

What small muscle stabilizes the posterior elbow?

Answer 11

Anconeus.

Question 12

What joints enable pronation and supination of the forearm?

Answer 12

Proximal and distal radioulnar joints.

Question 13

Which ligament holds the head of the radius in place?

Answer 13

Annular ligament.

Question 14

What muscles supinate the forearm?

Answer 14

Biceps brachii and supinator.

Question 15

What muscles pronate the forearm?

Answer 15

Pronator teres and pronator quadratus.

Question 16

How many carpal bones are in the wrist and what are their names?

Answer 16

8 (in two rows: proximal and distal).

Proximal:
Scaphoid
Lunate
Triquetral
Pisiform

Distal:
Hamate
Capitate
Trapezoid
Trapezium

Question 17

What are the joints of the wrist and hand?

Answer 17

Radiocarpal, midcarpal, carpometacarpal, metacarpophalangeal, proximal interphalangeal, distal interphalangeal joints.

Question 18

What are the motions of the wrist?

Answer 18

Flexion, extension, ulnar deviation, radial deviation.

Question 19

What are the superficial wrist flexors?

Answer 19

Flexor carpi ulnaris (FCU), flexor carpi radialis (FCR), palmaris longus.

Question 20

What nerve innervates flexor carpi ulnaris?

Answer 20

Ulnar nerve.

Question 21

What nerve innervates flexor carpi radialis and palmaris longus?

Answer 21

Median nerve.

Question 22

What muscles flex the fingers?

Answer 22

Flexor digitorum superficialis and flexor digitorum profundus.

Question 23

Which muscle flexes the thumb?

Answer 23

Flexor pollicis longus.

Question 24

Which muscles extend the thumb?

Answer 24

Extensor pollicis longus, extensor pollicis brevis, abductor pollicis.

Question 25

What nerve innervates all posterior forearm muscles?

Answer 25

Radial nerve.

Question 26

What are the superficial wrist extensors?

Answer 26

Extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris.

Question 27

What is the primary finger extensor?

Answer 27

Extensor digitorum.

Question 28

What structure prevents tendon bowstringing in the wrist?

Answer 28

Extensor retinaculum.

Question 29

What are the boarders and contents of the cuboidal fossa? What is this and where is it located?

Answer 29

- Transition zone in the elbow - Upside triangular in shape Boarders: - Top line is the intercondylar line - Left side: pronator teres - Right side: brachioradialis Contents: - Brachial artery - Brachial vein - Median nerve - Tendon of Bicep brachii

Question 30

What are the boarders and contents of the carpal tunnel? What is this and where is it located?

Answer 30

- Transition zone in the wrist - Tunnel shape Boarders: - Carpal arch underneath, formed by the carpal bones in the proximal end of the hand - Flexor retinaculum (transverse carpal ligamen) above Contents: - ulnar artery and vien - radial artery and vien - median nerve - 9 tendons of the wrist and finger flexors

Question 31

What muscles create motions of the wrist?

Answer 31

- extension: extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris - flexion: flexor carpi radialis, flexor carpi ulnaris, palmaris longus - ulnar deviation: flexor carpi radialis, felxor carpi ulnaris - radial deviation: extensor carpi radialis longus, extensor carpi radialis brevis, flexor carpi radialis

Question 32

What extrinsic muscles act on the hand?

Answer 32

- finger extensors: extensor digitorum - finger flexors: flexor digitorum profundus, flexor digitorum superficialis - thumb extensors: extensor pollicis longus, extensor pollicis brevis, abductor pollicis longus - thumb flexors: flexor pollicis longus