The Forearm

Question 1

describe the radius

Answer 1

• long bone in the forearm that lies laterally and parallel to the ulna
• pivots around ulna to produce movement

Question 2

how many places does the radius articulate in and what are they?

Answer 2

4 places - elbow joint, proximal radioulnar joint, wrist joint, distal radioulnar joint

Question 3

what are the important bony landmarks of the proximal region of the radius?

Answer 3

head, neck, radial tuberosity

Question 4

describe the ulna

Answer 4

• second long bone in forearm
• lies medially and parallel to the radius
• acts as the stabilising bone

Question 5

what does the ulna articulate with proximally and distally?

Answer 5

proximally = humerus
distally = radius

Question 6

describe the cubital fossa

Answer 6

• triangular in shape
• 3 borders = lateral, medial, superioral
• roof
• floor

Question 7

what are the contents of the cubital fossa? (lateral to medial)

Answer 7

• Really need beer to be at my nicest
• radial nerve
• biceps tendon
• brachial artery
• median nerve

Question 8

what is the anterior compartment of the forearm split into?

Answer 8

3 layers = superficial, intermediate, deep

Question 9

what innervates the anterior compartment of the forearm?

Answer 9

• mostly the median nerve, except for flexor carpi ulnaris and flexor digitorum profundus which = ulnar nerve

Question 10

how many superficial muscles are there in the anterior part of the forearm?

Answer 10

4 =
- flexor carpi ulnaris
- palmaris longus
- flexor carpi radialis
- pronator teres

Question 11

what muscle makes up the intermediate compartment of the anterior part of the forearm?

Answer 11

• flexor digitorum superficialis
• medial nerve and ulna artery pass between its 2 heads and then travel posteriorly

Question 12

how many deep muscles are there in the anterior compartment of the forearm?

Answer 12

3 =
- flexor digitorum profundus
- flexor pollicis longus
- pronator quadrutus

Question 13

what is the general function of the muscles in the posterior part of the forearm?

Answer 13

produce extension at the wrist and fingers

Question 14

how is the posterior part of the forearm innervated?

Answer 14

radial nerve

Question 15

what are the 2 layers of the posterior compartment of the forearm and how are they separated?

Answer 15

superficial and deep - separated by layer of fascia

Question 16

how many muscles are there in the superficial layer of the posterior compartment of the forearm and what are they?

Answer 16

7 =
1) brachioradialis
2) extesnor carpi radialis longus
3) and brevis
4) extensor digitorum communis
5) extensor digit minimi
6)extensor carpi ulnaris
7) anconeus

Question 17

how many muscles are there in the deep layer of the posterior part of the forearm and what are they?

Answer 17

5 =
1) supinator
2) abductus pollicis longus
3) extensor pollicis brevis
4) extensor pollicis longus
5) extesnor indicis

Question 18

what could radial nerve injury cause and why?

Answer 18

wrist drop as the radial nerve innervates extensor muscles therefore when these muscles are paralysed the wrist = drops