Glenohumeral Joint Flashcards
What are the 3 main elements that work together to maintain glenohumeral stability?
Ligaments, Labrum and Muscles
What are the Ligaments surrounding the GH Joint?
- Superior GH
- Medial GH
- Inferior GH
- Coracohumeral
- Coracoacromial
What is the function of the Superior GH Ligament?
Resists full adduction of the shoulder
What is the function of the Medial GH Ligament?
Resists excessive external rotation
What is the function of the Inferior GH Ligament?
Resists excessive abduction and internal/external rotation
What is the function of the Coracohumeral ligament?
Resists excessive extension, flexion and external rotation
What is the function of the Coracoacromial ligament?
Forms a bridge over the top of the joint, binding the coracoid to the acromion
What is the function of the labrum in the GH joint?
It deepens the glenoid cavity by forming a rim, which helps stability
What are the main stabilising muscles of the GH joint?
Rotator Cuff
Long head of Biceps
Long head of Triceps
What are the muscles of the rotator cuff?
- Subscapularis
- Supraspinatus
- Infraspinatus
- Teres Minor
In what directions does the long head of the biceps stabilise the GH joint?
Anterior and Superior
In what directions does the long head of the triceps stabilise the GH joint?
Posterior and Inferior
What is the origin, insertion and action of the Clavicular fibres of Pec Major?
- O: Anterior surface of medial half of clavicle
- I: Bicipital Groove of Humerus
- A: Flexion, Medial Rotation, Adduction
What is the origin, insertion and action of the sternal fibres of Pec Major?
- O: Anterior surface of sternum, upper 6 costal cartilages
- I: Bicipital Groove
- A: Extension, Adduction, Transverse Adduction and Medial Rotation
What is the origin, insertion and action of the Coracobrachialis?
- O: Tip of Coracoid Process (medial to short head of Biceps)
- I: Medial aspect of humerus
- A: Transverse Adduction
What is the origin, insertion and action of the Subscapularis?
- O: Medial and Lower 2/3 of the lateral border on costal surface of the scapula (Subscapular Fossa)
- I: Lesser tubercle, shoulder joint capsule and anterior upper shaft of humerus
- A: Stability and Internal Rotation
What is the origin, insertion and action of the Biceps Brachii?
- O: Supraglenoid tubercle (long head) and coracoid process (short head)
- I: Radial Tuberosity via biceps tendon
- A: Forearm Supination, Elbow Flexion, Shoulder Flexion, Stability
What is the origin, insertion and action of the Infrapsinatus?
- O: Infraspinous fossa
- I: Middle facet of greater tubercle of humerus
- A: External Rotation and Stability
What is the origin, insertion and action of the Teres Minor?
- O: 2/3 Lateral border of scapula
- I: Greater Tubercle of Humerus
- A: External rotation, adduction, stability
What is the origin, insertion and action of the anterior deltoid fibres?
- O: Anterior border of the lateral third of the clavicle
- I: V shaped deltoid tuberosity on lateral aspect shaft of humerus
- A: Flexion, internal rotation
What is the origin, insertion and action of the lateral delt fibres?
- O: Lateral border of acromion
- I: V Shaped deltoid tuberosity (lateral aspect shaft of the humerus)
- A: Abduction when int rotated, and trans abduction when ext rotated
What is the origin, insertion and action of the posterior delt fibres?
- O: Lower lip of scapular spine
- I: V shaped deltoid tuberosity (lateral aspect shaft of the humerus)
- A: Extension and External Rotation
What is the origin, insertion and action of the Supraspinatus?
- O: Supraspinous fossa
- I: Tendon inserts upper facet of greater humeral tubercle
- A: Initiation of abduction and stability
What is the origin, insertion and action of the Latissimus Dorsi?
- O: Spines and supraspinous ligaments T7-12, Posterior part of iliac crest, lower 4 ribs
- I: Inferior angle of the scapula, bicipital groove of the humerus
- A: Extension, Adduction, Internal Rotation
