Shoulder Joints Muscles And Movements

Question 1

What movements occur at the shoulder joint

Answer 1

Flexion/extension 
Abduction/adduction 
Medial/lateral rotation 
Elevation of the arm - through flexion or abduction 
Circumduction - combo of movements

Question 2

What is normal range of flexion and what muscles do this movement

Answer 2

Flexion - 110 degrees (from neutral) deltoid (anterior fibres), pectoralis major (clavicular head)

Question 3

What is normal range of extension and what muscles do this movement

Answer 3

Extension 50-70 degrees (from neutral) deltoid posterior fibres, teres major, latissimus dorsi, pectoralis major (sternocostal head) from flexion to neutral

Question 4

What is normal range of abduction and what muscles do this movement

Answer 4

Abduction - 100-120 degrees, deltoid middle fibres, supraspinatus initiates

Question 5

What is normal range of adduction and what muscles do this movement

Answer 5

Adduction - 30-40 degrees, pectoralis major, latissimus dorsi, teres major, coracobrachialis

Question 6

What is normal range of medial rotation and what muscles do this movement

Answer 6

Medial rotation - 90+ degrees, subscapularis, pectoralis major, latissimus dorsi, deltoid anterior fibres

Question 7

What is normal range of lateral rotation and what muscles do this movement

Answer 7

Lateral rotation - 80 degrees, infraspinstus, teres minor, deltoid posterior

Question 8

What causes the scapulohumeral rhythm

Answer 8

Glenohumeral joint

Scapulothoraccic joint

Question 9

What muscles act on the shoulder joint

Answer 9

Pectoralis major 
Latissimus dorsi 
Deltoid 
Teres major 
Coracobrachialis

Question 10

What’s muscles act on the rotator cuff

Answer 10

Supraspinatus
Infraspinatus
Teres minor
Subscapularis

Question 11

Explain the rotator cuff

Answer 11

The rotator cuff stabilises the glenohumeral joint through force coupled in both the coronal and transverse planes