Anatomy Lab 4

Question 1

Label the scapula in its different orientations

Answer 1

Question 2

Identify the 4 ‘rotator cuff’ muscles:
1) Subscapularis
2) Supraspinatus
3) Infraspinatus
4) Teres minor

What role does the rotator cuff play in the shoulder joint mechanism?

Answer 2

Act as a system of flexible/adjustable ligaments to hold the humeral head in its socket regardless of joint position. The rotator cuff act as synergists for many shoulder movements by preventing unwanted humeral head displacements caused by the actions of other muscles

Question 3

What role do the coracoid and acromion processes and the coraco-acromial ligament play in the stability
of the glenohumeral joint?

Answer 3

They prevent upward displacement of the humerus –
The GH joint only ever dislocates downwards

Question 4

In the anterior compartment of the arm identify:
- Long head of biceps
- Short head of biceps
- Coraco-brachialis
- Brachialis muscles
- Musculocutaneous nerve
- Median and ulnar nerves