Movements of the Shoulder Joint - The Muscles

Question 1

Which movements are permitted by the shoulder joint?

Answer 1

Flexion, Extension, Abduction, Adduction, Medial Rotation, Lateral Rotation

Question 2

Which muscles enable flexion at the shoulder joint? (upper limb forwards in the sagittal plane)

Answer 2

Pectoralis Major
Anterior Deltoid
Biceps brachii
Corachobrachialis

Question 3

Name the innervations of the flexors of the shoulder joint

Answer 3

Pectorals Major - lateral and medial pectoral nerve
Anterior Deltoid - axillary nerve
Biceps brachii - musculocutaneous nerve
Corachobrachialis - musculocutaneous nerve

Question 4

Which muscles enable extension at the shoulder joint? (upper limb backwards in the sagittal plane)

Answer 4

Posterior deltoid
Latissimus Dorsi
Teres Major

Question 5

Name the innervations of the extensors of the shoulder joint

Answer 5

Posterior deltoid - axillary nerve
Latissimus dorsi - thoracodorsal nerve
Teres Major - lower subscapular nerve

Question 6

Which muscles enable abduction at the shoulder joint?

Answer 6

0-15 degrees - supraspinatous
15-90 degrees - middle fibres of the deltoid
>90 degrees - scapula must be rotated, this is carried out by the trapezius and serratus anterior

Question 7

Name the innervations of the abductors of the shoulder joint

Answer 7

Supraspinatous - suprascapular nerve
Middle deltoid fibres - axillary nerve
Trapezius - accessory nerve
Serratus anterior - long thoracic nerve

Question 8

Which muscles enable adduction at the shoulder joint?

Answer 8

Pectoralis major
Latissimus dorsi
Teres major

Question 9

Name the innervations of the adductors of the shoulder joint

Answer 9

Pectoralis major - medial and lateral pectoral nerve
Latissimus dorsi - thoracodorsal nerve
Teres major - lower subscapular nerve

Question 10

Which muscles enable medial rotation at the shoulder joint?

Answer 10

Subscapularis 
Pectoralis major 
Latissimus dorsi 
Teres major 
Anterior deltoid

Question 11

Name the innervations of the medial rotators of the shoulder joint

Answer 11

Subscapularis - upper and lower subscapular nerve
Pectorals major - medial and lateral pectoral nerve
Latissimus dorsi - thoracodorsal nerve
Teres major - lower subscapular nerve
Anterior deltoid - axillary nerve

Question 12

Which muscles enable lateral rotation at the shoulder joint?

Answer 12

Infraspinatus

Teres minor

Question 13

Name the innervations of the lateral rotators of the shoulder joint

Answer 13

Infraspinatus - suprascapular nerve

Teres minor - axillary nerve

Question 14

Name the origin and insertion of Pectoralis major

Answer 14

Origin - medial half of clavicle, anterior surface of manubrium of sternum, anterior surface of body of sternum, costal cartilages of 1st-6th ribs, aponeurosis of external abdominal oblique
Insertion - lateral lip of intertubercular groove of humerus