Shoulder joint Flashcards
Shoulder joint known as
Glenohumeral joint
Other joints of shoulder girdle
Sternoclavicular
Acromioclavicular
Scapulothoracic
Glenohumeral joint articulations
Humeral head is larger than glenoid fossa (golf ball on tee)
Large range of movement (BUT unstable) but not heavy load
Glenohumeral joint type
Ball and socket synovial (WITH hyaline cartilage this time)
How is risk of dislocation of GH joint reduced
Glenoid labrum (fibrocartilaginous) deepens articulation
Joint capsule of GH
Loose
Reinforced by rotator cuff muscles
Inferior aspect has no reinforcement: WEAKEST point
Intracapsular ligaments glenohumeral joint
Superior
Middle
Inferior
Glenohumeral ligaments (on anterior joint so prevent anterior dislocation)
Extracapsular ligaments
Transverse humeral
Coracohumeral
Coracoacromial
Ligaments providing tunnels for tendons
Transverse humeral ligament - tunnel between greater and lesser tuberosities (holds long head biceps)
Coraco-acromial ligament - ‘roof’ arch tunnel above joint for supraspinatus tendon
ALSO PREVENTS ANTERIOR dislocation of humerus if falling on outstretched hand
Painful arc syndrome
Coracoacromial arch
Bursa lies between and compresses
Rotator cuff
Gives stability to shoulder joint
SITS
(supraspinatus, infraspinatus, teres minor, subscapularis)
Weakest part of shoulder joint
Inferior aspect
Static stabilisers of joint
Glenoid labrum
Joint capsule
Glenhumeral ligaments
Extracapsular ligaments (corocoacromial, corachohumeral)
Negative intrarticular pressure sucks in humerus head
Dynamic stabilisers shoulder
Rotator cuff
Extrinsic (biceps brachii, triceps brachii, deltoid, pectoralis major, coracobrachialis)
Right and left subclavian artery arise from
Right subclavian from brachiocephalic trunj
Left subclavian from aorta