Arthrology of the Shoulder girdle

Question 1

Sternoclavicular joint

Answer 1

Saddle joint.
Between sternum and clavicle.
Biplanar joint but with rotation movements.
- Interclavicular ligament
- Sternoclavicular ligament
- Costoclavicular ligament

Question 2

Interclavicular ligament

Answer 2

Of the sternoclavicular joint.
Between clavicles (lies on jugular notch between them).

Question 3

Sternoclavicular ligament

Answer 3

Of the sternoclavicular joint.

Between medial end of clavicle and lateral superior part of sternum.

Question 4

Costoclavicular ligament

Answer 4

Of the sternoclavicular joint.

Between the costal cartilage of 1st rib and inferior surface of medial part of clavicle.

Question 5

Acromioclavicular joint

Answer 5

Plane joint, two parallel surfaces, gliding movement.
Single plane joint. 
- Acromioclavicular ligament
- Coracoacromial ligament
- Coracoclavicular ligament

Question 6

Acromioclavicular ligament

Answer 6

Of the acromioclavicular joint.
Reinforces the articular capsule of the AC joint;
stabilizes in all directions.
Between medial border of acromion and lateral end of clavicle.

Question 7

Coracoacromial ligament

Answer 7

Of the acromioclavicular joint.
Prevents upward dislocation of the glenohumeral joint.
Between superior border of coracoid process and anterior part of acromion.

Question 8

Coracoclavicular ligament

Answer 8

Of the acromioclavicular joint.
Prevents dislocation of the AC joint.
- Trapezoid lig. (more anterior) between anterior surface of coracoid process and anterolateral part of clavicle.
- Conoid lig. (more posterior) around the posterior end of coracoid process and posterolateral part of clavicle.

Question 9

Glenohumeral joint

Answer 9

Spheroidal (Ball and socket) joint.
Highly mobile joint: Motion in all planes.
However, very unstable joint: Gravity favors instability and reduced contact surface between bones.
- Coracohumeral ligament
- Glenohumeral ligaments

Question 10

Coracohumeral ligament

Answer 10

Attach on both the greater and lesser tubercle of humerus and posterior part of coracoid process.
Covers the spot on glenoid cavity that is not covered by muscle or tendon.

Question 11

Glenohumeral ligaments

Answer 11

• Superior glenohumeral ligament
  O: Superior surface of the glenoid cavity
  I: Lesser tubercle of the humerus
• Middle glenohumeral ligament
  O: Anterior surface of the glenoid cavity
  I: Anatomical neck of the humerus
• Inferior glenohumeral ligament
  O: Inferior surface of the glenoid cavity
  I: Surgical neck of the humerus

Question 12

Articular capsule of glenohumeral joint

Answer 12

Fibrous capsule.
Not so tight, reinforced with strong capsular ligaments.
Surrounds the whole glenohumeral articulation.

Question 13

Glenoid labrum

Answer 13

Surround the glenoid cavity.
Fibrocartilage.
Doubles the depth of the glenoid cavity, enforces the suction of the glenoid fossa, negative pressure.

Question 14

Transverse humeral ligament

Answer 14

Covers the long head of bicep tendon.

From greater tubercle to lesser tubercle.

Question 15

Bursas

Answer 15

Filled with synovial fluid.
- Bursa subdeltoidea: avoids friction between deltoids and
humerus.
- Bursa subtendinea m. subscapularis: avoids friction
between subscapularis and thoracic structure.
- Bursa subacromialis protects supraspinatus from teardown
between humeral head and acromion.

Question 16

Protraction of the scapula

Answer 16

Moving the shoulder forward.

Question 17

Retraction of the scapula

Answer 17

Moving shoulder backwards.