Shoulder Joint

Question 1

Also known as…

Answer 1

Glenohumeral joint (Synovial ball and socket)

Question 2

Planes of movement?

Answer 2

Multiaxial

-wide range of movement at the expense of skeletal stability

Question 3

Articulation?

Answer 3

Between large spherical head of humerus and the small glenoid cavity of the scapula

Question 4

Narrow ridge around glenoid cavity?

Answer 4

Glenoid Labrum

Purpose: slightly deepens and enlarges the glenoid cavity

Question 5

Joint stability provided by..

Answer 5

1. rotator cuff muscles
2. long head of biceps brachii muscles
3. bony processes & ligaments

Question 6

Supporting structures:

Answer 6

3 thickenings of the articular capsule over the anterior surface of the joint form the glenohumeral ligaments
(Superior, middle, inferior)

Question 7

Support.. Transverse humeral ligament

Answer 7

• Between greater and lesser tubercles of the humerus

- they hold the tendon of long head of biceps brachii muscle in the intertubercular sulcus

Question 8

support.. Coracohumeral ligament (superiorly)

Answer 8

-extends from the coracoid process of the scapula to the greater tubercle of the humerus

Question 9

Bursae

Answer 9

• fluid filled sacs

- alleviate friction during various movements

Question 10

Movements of the shoulder joint: EXTENSION

Answer 10

Posterior deltoid, latissimus dorsi & teres major

Question 11

Movements of the shoulder joint: FLEXION

Answer 11

Biceps brachii (both heads), pectoralis major, anterior deltoid &coracobrachialis

Question 12

Movements of the shoulder joint: ABDUCTION

Answer 12

• First 0-15* produced by supraspinatus
• 15-90* middle fibres of the deltoid
• 90*–> -scapula needs to be rotated to achieve abduction
• Trapezius & serratus anterior - rotate

Question 13

Movements of the shoulder joint: ADDUCTION

Answer 13

Pectoralis major, latissimus dorsi & teres major

Question 14

Movements of the shoulder joint: MEDIAL ROTATION

Answer 14

Subscapularis, pectoralis major, latissimus dorsi, major & anterior deltoid

Question 15

Movements of the shoulder joint: LATERAL ROTATION

Answer 15

Infraspinatus & teres minor

Question 16

Movements of the shoulder joint: CIRCUMDUCTION

Answer 16

combination of all

Question 17

Rotator Cuff Muscles: (RCMs)

Answer 17

• 4 muscles most important to the shoulder joint
• they connect scapula to the humerus & provide support for the glenohumeral joint
• The tendons of each blend with the capsule of the ball and socket joint of the shoulder

Question 18

(RCMs): SUBSCAPULARIS MUSCLE

Answer 18

subscapular fossa - greater tubercle of humerus

Question 19

(RCMs): SUPRASPINATUS MUSCLE

Answer 19

supraspinous fossa - greater tubercle of humerus

Question 20

(RCMs): INFRASPINATUS MUSCLE

Answer 20

infraspinous fossa - greater tubercle of humerus (involved in lateral rotation of the shoulder)

Question 21

(RCMs): TERES MINOR MUSCLE

Answer 21

inferior angle of scapula - greater tubercle of humerus (involved in lateral rotation of the shoulder)

Question 22

*Pectoralis major

Answer 22

• Adduction & medial rotation of arm at glenohumeral joint
• also draws scapula anteriorly & inferiorly

Question 23

Blood and Nervous supply

Answer 23

Vascular - branches of the auxillary artery & the subclavian artery
Innervation - branches of the brachial plexus (suprascapular nerve, lateral pectoral nerve, auxillary nerve)