Session 5 - Joints: Elbow, forearm and wrist

Question 1

What are the articulations of the elbow joint?

Answer 1

Humerus, Ulna and Radius Humerus - Trochlea - Capitulum - Olecrannon Fossa - Coronoid Fossa - Radial Fossa Ulna - Coronoid process - Trochlear notch - Olecrannon process Radius - Head

Question 2

What type of joint is the elbow joint?

Answer 2

Hinge type synovial joint

Question 3

What happens at full extension of elbow?

Answer 3

Ulna makes an angle of 170* with the humerus

Question 4

What muscles produce the flexing hinge movemet of the elbow? What muscle extend the elbow?

Answer 4

Flexion: Brachialis, Biceps brachii, Brachioradialis Extension: Triceps brachii and Aconeus

Question 5

Describe the capsule of the elbow

Answer 5

• Weak anteriorly and posterioly - Strengthened by collateral ligaments medially and laterally - Capsule of the elbow shares with proximal radioulnar joint

Question 6

What are the two collateral ligaments which strengthen the elbow?

Answer 6

The ulna collateral ligament The radial collateral ligament

Question 7

What is the ulna collateral ligament made up of?

Answer 7

Three bands - Anterior, Posterior and Oblique (deepens socket for trochlea)

Question 8

Describe the radial collateral ligament of the elbow

Answer 8

Fan like, blends with annular ligament

Question 9

What lies underneath the fibrous capsule of the elbow joint?

Answer 9

Synovial membrane lines the fibrous capsule and humerus

Question 10

Label the diagram - What are A, B and C?

Answer 10

A - Radial collateral ligament B 0 Ulnar collateral ligament C - Annular ligament of radius

Question 11

What is the function of elbow bursae?

Answer 11

act to cushion the moving parts of a joint, preventing degenerative damage

Question 12

What are three important bursae of the elbow?

Answer 12

Intratendinosus - Formed within the tendon of the triceps brachii Subtendinosus - Found between the olecrannon and tedon of the triceps brachii, reducing friction during extension and flexion Subcutaneous - Found between olecrannon and overlying connective tissue

Question 13

What is subcutaneous bursitis of the elbow?

Answer 13

Repeated friction and pressure on the bursa can cause it become inflamed. Because this bursa lies relatively superficially, it can also become infected (e.g cut from a fall on the elbow), and this would also cause inflammation

Question 14

What is subtendinous bursitis?

Answer 14

This is caused by repeated flexion and extension of the forearm, commonly seen in assembly line workers. Usually flexion is more painful as more pressure is put on the bursa.

Question 15

What nerves are significant in elbow joint?

Answer 15

Radial nerve passes anterior to lateral epicondyle

Question 16

What are the three parts of the radioulnar joints?

Answer 16

Proximal Radioulnar joint Interosseous membrane Distal radio ulnar

Question 17

What is the proximal radioulnar joint formed by?

Answer 17

the head of the radius articulating with the radial notch of the ulna

Question 18

What is the head of the radius held in place by?

Answer 18

The annular ligament of the radius

Question 19

What prevents friction during movement of the proximal radioulnar joint?

Answer 19

The anular radial ligament is lined with a synovial membrane

Question 20

What is movement produced by in the proximal radioulnar joint?

Answer 20

the head of the radius rotating within the anular ligament on the capitulum of the humerus

Question 21

What are the two movements possible at the proximal radioulnar head, and how?

Answer 21

Pronation: Produced by the pronator quadratus and pronator teres Supination: Produced by the supinator and biceps brachii

Question 22

What is Hilton’s law?

Answer 22

The principle that the nerve supplying a joint also supplies both the muscles that move the joint and the skin covering the articular insertion of those muscles.

Question 23

What is the interosseous membrane of the radioulna joint?

Answer 23

Fibrous joint which allows distribution of force from radius to ulna

Question 24

What does the distal radioulna joint consist of?

Answer 24

The head of the ulnar and the ulnar notch on the side of the radius.

Question 25

What strengthens the distal radioulna joint?

Answer 25

• Anterior and posterior ligaments - Fibrocartilaginous ligament called articular disk

Question 26

What are the two roles of the articular disk at the distal radioulna joint?

Answer 26

• Binds the radius and ulna together, and holds them together during movement at the joint - Separates the distal radioulnar joint from the wrist joint

Question 27

What type of joints are the proximal and distal radioulna joints?

Answer 27

Pivot

Question 28

What two movements is the distal radioulna joint capable of?

Answer 28

Pronation: Produced by the pronator quadratus and pronator teres Supination: Produced by the supinator and biceps brachii

Question 29

What occurs during pronation and supination of the distal radioulna joint?

Answer 29

he ulnar notch of the radius slides anteriorly over the head of the ulnar during such movements.

Question 30

What is the name for the structure which allows twisting of the synovial capsula at the distal radioulna joint?

Answer 30

Sacciform recess

Question 31

What is the wrist joint formed from?

Answer 31

The wrist joint is formed by the articulation of distal end of the radius, the articular disk and the proximal row of the carpal bones (except the pisiform).

Question 32

What prevents the ulna interacting with the wrist joint?

Answer 32

Prevented by articular disk

Question 33

What type of joint is the wrist joint?

Answer 33

Synovial, condyloid joint

Question 34

What three things contribbute to stability of wrist joint?

Answer 34

The joint capsule, structure of the joint and the associated ligaments

Question 35

How does the joint capsule contribute to stability?

Answer 35

The fibrous outer layer attaches to the radius, ulna and the proximal row of the carpal bones. The internal layer is comprised of a synovial membrane, secreting synovial fluid, lubricating the joint

Question 36

How does the structure of the wrist joint contribute to stabiity?

Answer 36

Excessive abduction of the wrist is prevented by the radial styloid process.

Question 37

Name four ligaments of the wrist

Answer 37

Palmar radiocarpal Dorsal radiocarpal Ulnar collateral Radial collateral

Question 38

What is the function of the palmar radiocarpal ligament, other than stability

Answer 38

ensure that the hand follows the forearm during supination

Question 39

What is the function of the dorsal radiocarpal ligament, other than stability

Answer 39

ensures that the hand follows the forearm during pronation

Question 40

What movements is the wrist joint capapble of?

Answer 40

flexion, extension, adduction and abduction

Question 41

What muscles contribute to flexion of the wrist?

Answer 41

Flexor Carpi Ulnaris Flexor Carpi Radialis Flexor Digitorum Superficialis Flexor Digitorum Profundus Palmaris Longus

Question 42

What muscles contribute to extension of the wrist?

Answer 42

Extensore Carpi Radialis longus Extensor Carpi radialis brevis Extensor carpi ulnaris Extensor digitorum Extensor pollicis longus extensor indices

Question 43

What muscles contribute to adduction of the wrist?

Answer 43

Extensor carpi ulnaris and Flexor carpi ulnaris

Question 44

What muscles contribute to abduction of the wrist?

Answer 44

Abductor pollicis longus, Flexor carpi radialis, Extensor carpi radialis longus and brevis.

Question 45

What is the vascular supply of the elbow?

Answer 45

Arterial anastamoses formed by collateral arteries and recurrent branches of ulnar, radial and interosseous arteries