AP04 - the shoulder and pectoral girdle

Question 1

What bones do the muscles of the rotator cuff attach to, and what is their general function?

Answer 1

the scapula and humerus, they pull the humeral head into the glenoid fossa

Question 2

What separates the thoracic cage and the scapula?

What is its’ function and innervation?

Answer 2

subscapularis

medial rotation of the humeral head in the glenoid fossa

upper and lower subscapular nerves (from posterior brachial plexus)

Question 3

What are the 5 ligaments of the shoulder joint, note whether they are within the joint capsule or not

Answer 3

glenohumeral ligament (within)
transverse humeral ligament (within)
coracohumeral ligament (outside)
Coracoclavicular ligament (outside)
Acromioclavicular ligament

Question 4

Name 2 bursae in the shoulder

Answer 4

subacromial

subtendonous

Question 5

What are the 4 rotator cuff muscles, and their innervation?

Answer 5

Subscapularis (upper and lower subscapular nerve)
Supraspinatus (suprascapular nerve)
Infraspinatus (suprascapular nerve)
Teres Minor (axillary nerve)

Question 6

Describe the function of supraspinatus

Answer 6

abducts the arm independently up to 15 degrees, and then with the deltoid up to 90 degrees

Question 7

Describe the function of infraspinatus AND teres minor

Answer 7

lateral rotation

Question 8

What stabilises the tendon of the long head of the biceps brachii?

Answer 8

The greater and lesser tubercles

the transverse humeral ligament

Question 9

What are the divisions of the deltoid and their functions?

Answer 9

anterior - flexion and medial rotation
middle -abduction
posterior - extension and lateral rotation

Question 10

What comprises the anterior border of the axilla?

Answer 10

pectoralis major and minor

Question 11

What comprises the medial border of the axilla?

Answer 11

serratus anterior and the thoracic wall

Question 12

What comprises the posterior border of the axilla?

Answer 12

scapularis, teres major, lataissimus dorsi

Question 13

What is trapezius innervated by and what is its’ function?

Answer 13

scapula elevator and rotator (in abduction)

(CN XI) Spinal Accessory

Question 14

What is deltoid innervated by?

Answer 14

axillary nerve

Question 15

What is levator scapulae innervated by?

Answer 15

anterior rami of C3 and C4 and C5 from the dorsal scapular narve

Question 16

What is the function of rhomboid major and minor and their innervations?

Answer 16

elevation and retraction of the scapula

dorsal scapular nerve (C4, C5)

Question 17

What is the difference in function and innervation of teres minor and major?

Answer 17

teres minor - axillary nerve, lateral rotation of arm at shoulder

teres major - inferior subscapular nerve, medial rotation AND EXTENSION of the arm at the glenohumeral joint

Question 18

What is the triceps brachii innervated by?

Answer 18

radial nerve

Question 19

What is the suprascapular foramen?

What passes through it?

Answer 19

route for structures to pass between base of the neck and the posterior scapular region

suprascapular nerve
(suprascapular artery and vein don't follow the same course, but pass superior to the superior transverse scapular ligament)

Question 20

What is the quadrangular space?

What passes through it?

Answer 20

passage between axilla and posterior scapular region

axillary nerve
posterior circumflex humeral artery and vein

Question 21

What is the triangular space, and what passes through it?

Answer 21

communication between axilla and posterior scapula region

circumflex scapular artery and vein

Question 22

What is the triangular interval and what passes through it?

Answer 22

passage between anterior arm and axilla, and posterior arm.

radial nerve
profunda brachii artery, and associated veins