What are the bones that make up the shoulder girdle?
Clavicle and scapula
Describe the clavicle: type of bone, key landmarks, articulation (makes what joint), function, muscle and ligament attachment
- Long bone, lateral end: flat, broad, sternal end: round, small
- Acromial facet on lateral end articulates with acromion of the scapula forming the acromioclavicular joint.
- Sternal facet on the sternal end articulates with clavicular notch of the manubrium of sternum forming the sternoclavicular joint. (attach to axial skeleton)
- Pushes upper limb out to the side enabling great range of motion.
- Roughening on inferior surface of lateral end provides attachment for coracoclavicular ligament.
- Roughening on inferior surface of sternal end provides attachment for costoclavicular ligament.
Describe the scapula: type of bone, key landmarks, articulation (makes what joint), function, muscle and ligament attachment
- Flat bone
- Clavicular facet on medial border of acromion articulates with acromial end of clavicle forming the acromioclavicular joint.
- Glenoid fossa on lateral end of scapula articulates with head of humerus forming the glenohumeral joint (shoulder joint).
- Stabilise bones involved in shoulder movement.
- Fossae (depressions) for muscle attachment.
Describe sternoclavicular joint: type of joint, movements allowed, ligaments attached
- saddle type synovial joint
- Elevation, depression, protraction, retraction and rotation of the shoulders.
- Sternoclavicular ligaments (anterior and posterior)
- Costoclavicular ligament (very strong, main stabilising force of the joint, resisting elevation of the pectoral girdle)
- Strong capsule
Describe acromioclavicular joint: type of joint, movements allowed, ligaments attached
- plane synovial joint
- all movements are passive, axial rotation to a degree
- Acromioclavicular ligament (covers joint capsule, reinforcing superior aspect)
- Conoid and trapezoid ligament making the coracoclavicular ligament (help stabilise joint- very strong)
- Weak capsule
Which shoulder girdle joint is commonly injured?
- Acromioclavicular joint
- Fall on outstretched hand
What are common sites of injury of the humerus?
- Surgical neck of humerus, midshaft and supracondylar
Which muscle attaches to lesser tuberosity of humerus?
- subscapularis muscle
Which muscles attaches to greater tuberosity of humerus?
- supraspinatus muscle, infraspinatus muscle, teres minor
Which muscle attaches to scapula and runs through the bicipital groove of the humerus?
- Long head of biceps brachii
Which muscle attaches to coracoid process of scapula?
- Short head of biceps brachii
Which muscles attaches to lateral epicondyle of humerus?
- extensor carpi ulnaris, extensor digitorum, extensor carpi radialis brevis, extensor digiti minimi
Which muscles attaches to medial epicondyle of humerus?
- flexor carpi radialis, flexor digitorum superficialis, flexor carpi ulnaris
What does the capitulum of the humerus articulate with?
- head of radius
What does the trochlea of the humerus articulate with?
- the trochlear notch of the ulna
What type of joint is the glenohumeral joint? What supports this unstable joint?
- Synovial ball and socket joint
- Supported by glenoid labrum, coracoaromial ligament, rotator cuff muscles, long head of biceps
What are the rotator cuff muscles of the shoulder?
- Supraspinatus, infraspinatus, teres minor, subscapularis
What is the physiological joint of the shoulder? (not true joint)
- scapulo-thoracic joint
Where is the clavicle most commonly fractured and why?
- The junction between the two curvatures because the coracoclavicular ligament is quite strong here and so the clavicle will fracture before the ligament is broken.
What position of shoulder joint dislocation is most common?
- Anterior shoulder joint dislocation
- Occurs when force is applied to abducted and externally rotated arm
What type of bone is the humerus, ulna and radius?
- Long bones
What links the ulna and the radius?
- Interosseous membrane
Which muscles attaches to the olecranon process of the ulna?
- triceps muscles (long head, lateral head and medial head of triceps brachii)
Which muscles attaches to the radial tuberosity of the radius?
- biceps muscles (long head and short head of bicpes brachii
