MSK - Shoulder And Back

Question 1

What lines the articulating surface of the shoulder joint?

How is the glenoid cavity deepened?

Answer 1

Hyaline cartilage

Glenoid labrum

Question 2

What makes the shoulder joint relatively unstable?

How is stability achieved? (4)

Answer 2

Shallow glenoid cavity
Disproportion of articular surfaces
Multiplanar movements
Lax capsule

Rotator cuff muscles
Other muscles
Ligaments
Capsule

Question 3

What is the capsule of the shoulder attached to?

What feature allows movement?

What allows full abduction?

Answer 3

Glenoid labrum and margins of glenoid cavity
Anatomical neck of humerus

Tough but lax

Bridges intertubular groove and dips down medially to surgical neck

Question 4

What is the purpose of the synovial membrane?

The tendon of what muscle lies within the joint cavity?

What does the tendon acquire as it enters the joint?

What does the gap in the capsule allow?

Answer 4

Line capsule and lines bone within capsule up to edge of articulating surfaces

Long head of biceps
Acquires a tubular sleeve of synovium which surrounds tendon up to its insertion

Synovium and joint cavity to be continuous with subscapular bursa

Question 5

What are the three extracapsular ligaments?

And what are their locations?

Answer 5

Coracoacrmoial ligament - between acromion and Coracoid process

Coracohumeral ligament - base of Coracoid process to anterior part of greater tubercle

Transverse humeral ligament - holds tendon of long head of biceps in place during shoulder movement

Question 6

What are the intracapsular ligaments?

Where do they extend between?

What reinforces the capsule anteriorly?

Answer 6

Three gleno-humeral ligament - Superior, middle, inferior

Glenoid labrum and humerus

Part of fibrous capsule - can only be seen from inside the capsule

Question 7

What forms the coraco acromial arch?

Answer 7

Coracoacromial ligament, acromion and coracoid process

Question 8

What type of joint is the shoulder joint?

What is another name of the shoulder joint?

What does this type of joint allow?

What commonly occurs at this joint?

Answer 8

Ball and socket type - Synovial joint

Gleno humeral joint

Wide range of movements in multiple planes

Most mobile, least stable.

Dislocations