Anatomy

Question 1

What is the action of pectoralis major on the gleno-humoral joint?

Answer 1

Adduction, flexion and medial rotation.

Question 2

What muscles contribute to form the anterior border of the axilla?

Answer 2

Pectoralis major and pectoralis minor

Question 3

What are the terminal branches of the posterior cord of the brachial plexus?

Answer 3

Radial and axillary nerve

Question 4

From which part of the brachial plexus does the nerves supply to latissimus dorsi arise?

Answer 4

Thoracodorsal nerve arises from the posterior cord

Question 5

Which muscle does the musculocutaneous nerve normally pierce?

Answer 5

Coracobrachialis

Question 6

Which nerves normally form the roots of the brachial plexus?

Answer 6

Anterior (ventral) rami of spinal nerves in region of C5-T1

Question 7

What is the scapular attachment of the pectoralis minor?

Answer 7

The coracoid process

Question 8

Why would the action of the serratus anterior rarely be affected by a lesion of the brachial plexus?

Answer 8

It is supplied by the long thoracic nerve which arises very proximal so is unlikely to be affected by lesions of the brachial plexus.

Question 9

Which 3 joints make up the elbow?

Answer 9

• humeroulnar joint
• humeroradial joint
• proximal radioulnar joint

Question 10

What movements are facilitated through the elbow joints?

Answer 10

• flexion
• extension
• pronation
• supination

Question 11

How is the elbow joint stabilised?

Answer 11

From the bony articulations of the trochlea (humerus) and olecranon (ulna).

Question 12

Where does the humerus articulate with the radius and ulna?

Answer 12

• radius articulates with capitulum

- ulna articulates with trochlea

Question 13

What is an epicondyle?

Answer 13

A prominence on the distal part of a long bone which serves as an attachment for muscles and ligaments.

Question 14

What is an aponeurosis?

Answer 14

A broad flat sheet of dense, fibrous, collagenous connective tissue that covers, invests and forms the terminations and attachments of various muscles.

Question 15

Describe the humeroulnar joint.

Answer 15

• main joint of the elbow
• medial
• articulation between trochlea of humerus and trochlear notch of ulna
• reinforced by the ulnar collateral ligament
• allows for flexion and extension
• not involved in pronation/supination

Question 16

Describe the humeroradial joint.

Answer 16

• lateral
• articulation between the capitulum of humerus and head of radius
• reinforced by the radial collateral ligament
• allows for pronation and supination

Question 17

Describe the superior radioulnar joint.

Answer 17

• associated with elbow
• pivot synovial joint
• articulation between head of radius and osseofibrous ring (radial notch of the ulna and anular ligament)
• radial head is held in position by the anular ligament of the radius
• allows for pronation and supination of the forearm

Question 18

Describe the inferior radioulnar joint.

Answer 18

• pivot synovial joint
• articulation between the head of the ulna and the ulnar notch of the radius
• held together by an articular disc and interosseous membrane

Question 19

Describe the ulna.

Answer 19

• medial and longer than the radius
• at proximal end contains the trochlear notch, coranoid process anteriorly, olecranon process posteriorly
• at distal end contains head of ulna and styloid process

Question 20

Describe the radius.

Answer 20

• lateral
• at proximal end contains head of radius and radial tuberosity medially (biceps attach here)
• at distal end contains styloid process laterally and ulnar notch medially
• distal end articulates with ulna and proximal carpal bones

Question 21

List the bursae around the elbow joint.

Answer 21

• intratendinous olecranon bursa
• subtendinous olecranon bursa
• subcutaneous olecranon bursa
• bicipitoradial (biceps) bursa (separates biceps tendon from anterior part of radial tuberosity)

Question 22

Which muscles act as flexors of the arm?

Answer 22

• biceps brachii
• Coracobrachialis
• brachialis

Question 23

Which muscles act as extensors of the arm?

Answer 23

• triceps

- aconeus

Question 24

Describe pronation of the forearm.

Answer 24

• palm turned posteriorly
• proximal radius lateral to ulna
• distal radius medial to ulna

Question 25

Describe supination of the forearm.

Answer 25

• palm turned anteriorly
• pronation movement reversed
• radius lateral to and parallel with ulna

Question 26

List the ligaments associated with the elbow.

Answer 26

• radial annular ligament
• ulnar collateral ligament
• radial collateral ligament

Question 27

What muscles are involved in pronation and supination?

Answer 27

Supination - biceps brachii

Pronation - pronator teres, pronator quadratus and possibly aconeus

Question 28

Describe the cubital fossa.

Answer 28

• important transition between arm and forearm
• concavity under crease, anterior to elbow joint
• triangular depression bound by brachioradialis laterally and pronator teres medially
• median nerve runs through
• radial nerve found laterally if brachioradialis is retracted

Question 29

List the muscles of the anterior compartment of the forearm.

Answer 29

Superficial: pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris
Intermediate: flexor digitorum superficialis
Deep: flexor digitorum profundus, flexor pollicis longus, pronator quadratus

Question 30

List the muscles of the posterior compartment of the forearm.

Answer 30

Superficial: brachioradialis, extensor carpi radialis longus, extensor carpi radialis breves, extensor digiti minimi, extensor carpi ulnaris
Deep: supinator, extensor indicis, abductor pollicis longus, extensor pollicis longus, extensor pollicis brevis