Shoulder Joint

Question 1

What type of joint is the shoulder joint?

Answer 1

Synovial ball and socket

Question 2

Where is the shoulder joint?

Answer 2

Between the rounded humeral head of the humerus and the shallow glenoid fossa

Question 3

What movements can occur at the shoulder joint?

Answer 3

Flexion and extension.
Abduction and Adduction.
Medial and lateral rotation

Question 4

What are the articular surfaces involved in the shoulder joint?

Answer 4

Humerus and glenoid fossa

Question 5

Does the articular surfaces provide stability?

Answer 5

Provide little stability due to the arrangement

Question 6

What covers the articular surfaces?

Answer 6

Hyaline cartilage

Question 7

Describe the articular surface do the glenoid fossa

Answer 7

Faces laterally, anteriorly and slightly superiorly.
Concavity is irregular
Fossa just over one-third of the humeral articular surface

Question 8

What is the glenoid fossa deepened by?

Answer 8

Glenoid labrum

Question 9

Describe the articular surface of the humerus?

Answer 9

Faces superiorly, medially and posteriorly, only one-thrip of the humeral head is in contact with the glenoid fossa

Question 10

Describe the joint capsule?

Answer 10

Fibrous joint capsule, loose cylindrical sleeve, fibres mainly horizontally orientated

Question 11

What does the joint capsule attach to?

Answer 11

Glenoid labrum

Question 12

Does the joint capsule provide stability?

Answer 12

Little stability

Question 13

Where does the capsule attach to?

Answer 13

The neck of the humerus at articular margin and extends inferiorly

Question 14

Anteriorly the capsule is strengthened by?

Answer 14

Three ligaments

Question 15

What attaches to the capsule superoposteriorly?

Answer 15

Coracohumeral ligament

Question 16

What is important in joint integrity?

Answer 16

Rotator cuff muscles span over the capsule to provide reinforcement to blend near humeral attachment

Question 17

What lines the inner surface of the capsule?

Answer 17

Synovial membrane

Question 18

What are the intra-articular structures?

Answer 18

Glenoid labrum and long head of biceps brachii

Question 19

Describe the glenoid labrum

Answer 19

Fibrocartilaginous ring that deepens the glenoid fossa and the outer surface gives attachment to the long head of biceps brachii tendon

Question 20

What are the ligaments involved in the shoulder joint?

Answer 20

Superior glenohumeral, middle glenohumeral, inferior glenohumeral, transverse humeral.

Coracohumeral and Coracoacromial

Question 21

What is the primary limiter of inferior translation of adducted shoulder?

Answer 21

Superior glenohumeral ligament

Question 22

What resists anterior translation?

Answer 22

Middle glenohumeral

Question 23

What is the inferior glenohumeral divided into?

Answer 23

Anterior and posterior bands

Question 24

What does the anterior band of the inferior glenohumeral limit?

Answer 24

Inferior translation and external rotation

Question 25

What does the posterior band of the inferior glenohumeral ligament limit?

Answer 25

Internal rotation

Question 26

During lateral rotation, what ligaments are taut?

Answer 26

Superior, middle and inferior glenohumeral

Question 27

During medial rotation what ligaments are lax?

Answer 27

Superior, middle and inferior glenohumeral

Question 28

What ligaments are taut during abduction?

Answer 28

Middle and inferior glenohumeral

Question 29

What muscles are involved in flexion?

Answer 29

Anterior deltoid fibres, coracobrachiallis and biceps brachii

Question 30

Degrees of flexion?

Answer 30

110-180

Question 31

Degrees of extension?

Answer 31

70-90

Question 32

What is extension limited by?

Answer 32

Greater tubercle of humerus contacting the coracoacromial arch

Question 33

What muscles are involved in extension?

Answer 33

Posterior deltoid fibres, theres major, latissimus dorsi

Question 34

Is it concentric contraction or eccentric contraction of muscle that produce flexion?

Answer 34

Eccentric

Question 35

What is abduction limited by?

Answer 35

Lateral rotator and posterior capsule tension

Question 36

What muscles are involved in adduction?

Answer 36

Eccentric contraction of serrates anterior, trapezius, deltoid and supraspinatus

Question 37

What muscle is involved in lateral rotation?

Answer 37

Infraspinatus, teres minor and posterior fibres of deltoid

Question 38

ROM of lateral rotation?

Answer 38

80 degrees

Question 39

ROM of medial rotation?

Answer 39

Less than 90 degrees

Question 40

What muscles are involved in medial rotation?

Answer 40

Subscapularis, pectoralis major, latissimus dorsi, teres major and anterior deltoid fibres

Question 41

Joint stability is sacrificed for?

Answer 41

Mobility

Question 42

What is the stabilising factor for this joint?

Answer 42

Muscle tone

Question 43

What do big muscles produce?

Answer 43

Movements

Question 44

What do little muscles produce

Answer 44

Stability

Question 45

What does the anterior capsule resist?

Answer 45

Anterior displacement between 70-90 degrees abduction

Question 46

What does the posterior capsule resist?

Answer 46

Posterior displancemtn between 50-90 degrees abduction

Question 47

What provides initial stability during 40-50 degrees of abduction?

Answer 47

Anterior capsule and rotator cuff muscles

Question 48

What loops around head of humerus to act as a sling?

Answer 48

Triceps brachii

Question 49

How does the rotator cuff muscles aid stability?

Answer 49

Rotator cuff muscle and deltoid contraction pulls the head of the humerus into the glenoid fossa