Joints of upper limb

• The shoulder joint is articulated between the head of the humerus and the glenoid cavity of the scapula.
• The shoulder joint is a ball-and-socket joint, with the head of the humerus as the ball and the glenoid cavity of the scapula as the socket.
• The glenoid labrum is a part of the articular surface of the shoulder joint, covered by Hyaline cartilage.
• The capsule surrounds the shoulder joint, is thin and lax, allowing a wide range of movement, and is strengthened by the tendons of the rotator cuff.
• The medial margin of the glenoid cavity and the neck of the humerus are attachments of the capsule.
• There are two openings in the capsule: a small opening anteriorly, where the synovial membrane communicates with the subscapular bursa, and a smaller opening that allows the tendon of the long head of biceps brachii to arise from the supraglenoid tubercle of the scapula.
• The superior glenohumeral ligament, the middle glenohumeral ligament, and the inferior glenohumeral ligament are parts of the glenohumeral ligaments.
• The transverse humeral ligament bridges the gap between the two tuberosities of the humerus.
• The coracohumeral ligament, the coracoclavicular ligament, and the coracoacromial ligament are parts of the ligaments around the shoulder joint.
• The subscapular bursa and the subacromial bursa are bursae around the shoulder joint.
• The coracoacromial arch is a strong, osteoligamentous structure which includes the smooth under-surface of the acromion, the coracoacromial ligament, the coracoid process, and overlies the head of the humerus, preventing its upward displacement from the glenoid fossa.
• During abduction, there is a risk of soft tissue impingement between the head of the humerus and the acromion.
• The shoulder joint has a wide range of movement, and the stability of the joint has been sacrificed to permit this movement.
• The following movements are possible in the shoulder joint: flexion, extension, abduction, adduction, lateral rotation, medial rotation and circumduction.
• Static stabilizers of the shoulder joint include the glenohumeral ligaments, the capsule, and the labrum.
• Dynamic stabilizers of the shoulder joint include the rotator cuff muscles, the scapulothoracic musculators, and the long head of biceps muscle.
• The elbow joint is an articulation between the trochlea and capitulum of the humerus, and the trochlear notch of the ulna and head of the radius.
• The elbow joint is a synovial hinge joint.
• The elbow joint is surrounded by a capsule, which is anteriorly weak and posteriorly strengthened by the medial and lateral collateral ligaments.
• The elbow joint and the proximal radioulnar joint share a capsule.
• The lateral collateral ligament is attached to the lateral epicondyle of the humerus and the anular ligament.
• The medial collateral ligament consists of three bands: anterior, posterior, and transverse, which are attached to the medial epicondyle of the humerus and ulna.
• The synovial membrane lines the capsule of the elbow joint.
• Bursae are located around the elbow joint.
• The radial nerve passes anterior to the lateral epicondyle.
• The ulnar nerve passes posterior to the medial epicondyle.
• The median nerves passes anteriorly in the middle and then between the radius and ulna.
• Flexion of the elbow is performed by brachialis, biceps, brachioradialis, pronator teres.
• Extension of the elbow is performed by triceps and anconeus.
• The carrying angle is the angle between the long axis of the arm and the axis of the forearm with the elbow joint fully extended and forearm supinated.
• The proximal radioulnar joint is an articulation between the head of the radius and the radial notch on the ulna.
• The distal radioulnar joint is an articulation between the head of the ulna and the ulnar notch on the radius.
• The wrist (radiocarpal) joint is an articulation between the distal end of the radius above and the scaphoid, lunate, and triquetral bones below.
• The wrist joint is a synovial ellipsoid joint.
• The wrist joint is surrounded by a capsule, which is anteriorly weak and posteriorly strengthened by the medial and lateral collateral ligaments.
• The wrist joint is surrounded by the anular ligament, which ensures the hand follows the radius in supination and pronation.
• The wrist joint allows flexion, extension, abduction, and adduction.
• Abduction of the wrist is limited by the styloid process of the radius.