Rotator Cuff

Question 1

What are the rotator cuff muscles?

Answer 1

Supraspinatus
Infraspinatus
Teres minor
Subscapularis

Question 2

What is the origin and insertion of supraspinatus?

Answer 2

Origin: Supraspinatus fossa
Insertion: Greater tuberosity of humerus

Question 3

What is the innervation of supraspinatus?

Answer 3

Suprascapular nerve C5/C6

Question 4

What is the action of supraspinatus?

Answer 4

Initiates the first 15degrees of arm abduction (before deltoid takes over)

Question 5

What is the origin and insertion of infraspinatus?

Answer 5

Origin: Infraspinatus fossa
Insertion: Greater tuberosity of humerus

Question 6

What is the innervation of infraspinatus?

Answer 6

Suprascapular nerve C5/C6

Question 7

What is the action of infraspinatus?

Answer 7

Externally rotates the arm

Question 8

What is the origin and insertion of teres minor?

Answer 8

Origin: Dorsal surface of lateral scapular
Insertion: Greater tuberosity of humerus

Question 9

What is the innervation of teres minor?

Answer 9

Axillary nerve C5/C6

Question 10

What is the action of teres minor?

Answer 10

Externally rotates the arm

Question 11

What is the origin and insertion of subscapularis?

Answer 11

Origin: subscapular fossa
Insertion: Lesser tuberosity of humerus

Question 12

What is the innervation of subscapularis?

Answer 12

Upper and lower subscapular nerve C5/C6

Question 13

What is the action of subscapularis?

Answer 13

Internally rotates the arm

Question 14

What is painful arc syndrome and what causes it?

Answer 14

Painful on abduction from 50-130 degrees due to impingement of the superspinatus tendon between the humerus and acromion

Question 15

What is the ‘tendinous cuff’ and what is its function?

Answer 15

The distal tendons of the rotator cuff muscles all blend together to reinforce and stabilise the glenohumeral joint