Joints of the Upper Limb
The joints of the shoulder girdle
The sternoclavicular joint
Type:
The sternoclavicular joint is a saddle synovial joint.
Articulation
The sternal end of the clavicle articulates with the clavicular notch of the manubrium sterni and with the first costal cartilage.
Ligaments
The ligaments holding this joint are:
1)The anterior and posterior sternoclavicular ligaments.
2)The costoclavicular ligament, which is a strong ligament which extends from the upper surface of the first rib to the inferior surface of the sternal end of the clavicle that fixes the clavicle and prevents its upward dislocation.
3)The interclavicular ligament that connects the medial ends of the two clavicles.
The articular disc:
A fibrocartilaginous disc divides the joint cavity into lateral and medial compartments called the intracapsular structure.
Capsule
The fibrous capsule of this joint is attached to the margin of the articular surfaces and forms by the thickened surrounding ligaments.
The synovial membrane
The synovial membrane lines the inner surface of the joint capsule.
Nerve supply
The nerve to subclavius and the supraclavicular nerve supply this joint.
Movement
This joint allows the elevation and depression in the lateral compartment of the joint, while the medial compartment allows the forward and backward movement. Serratus anterior is related to the forward movement, while trapezius and the rhomboid muscles produce the backward movement. Trapezius and sternocleidomastoid produce the elevation, while the depression is produce by pectoralis minor and subclavius.
The sternoclavicular joint
Type:
The sternoclavicular joint is a saddle synovial joint.
Articulation
The sternal end of the clavicle articulates with the clavicular notch of the manubrium sterni and with the first costal cartilage.
Ligaments
The ligaments holding this joint are:
1)The anterior and posterior sternoclavicular ligaments.
2)The costoclavicular ligament, which is a strong ligament which extends from the upper surface of the first rib to the inferior surface of the sternal end of the clavicle that fixes the clavicle and prevents its upward dislocation.
3)The interclavicular ligament that connects the medial ends of the two clavicles.
The articular disc:
A fibrocartilaginous disc divides the joint cavity into lateral and medial compartments called the intracapsular structure.
Capsule
The fibrous capsule of this joint is attached to the margin of the articular surfaces and forms by the thickened surrounding ligaments.
The synovial membrane
The synovial membrane lines the inner surface of the joint capsule.
Nerve supply
The nerve to subclavius and the supraclavicular nerve supply this joint.
Movement
This joint allows the elevation and depression in the lateral compartment of the joint, while the medial compartment allows the forward and backward movement. Serratus anterior is related to the forward movement, while trapezius and the rhomboid muscles produce the backward movement. Trapezius and sternocleidomastoid produce the elevation, while the depression is produce by pectoralis minor and subclavius.
The acromioclavicular joint
Type
The acromioclavicular joint is a synovial of plane variety.
Articulation
The articulating surfaces are between the lateral end of the clavicle and the medial margin of the acromion.
Ligaments
This joint supported by the superior and inferior acromioclavicular ligament, which are the thickened upper and lower parts of the capsule.
The coracoclavicular ligament from the coracoid process to the inferior surface of the clavicle.
Articular disc
The articular disc of the acromioclavicular joint is incomplete.
Capsule
The fibrous capsule of this joint is attached to the margin of the articular suraces and forms by the thickened surrounding ligaments.
Synovial membrane
The synovial membrane lines the inner surface of the joint capsule.
Nerve supply
The suprascapular nerve.
Movement
Some gliding movement is allowed when the scapula change its position.
Type
The acromioclavicular joint is a synovial of plane variety.
Articulation
The articulating surfaces are between the lateral end of the clavicle and the medial margin of the acromion.
Ligaments
This joint supported by the superior and inferior acromioclavicular ligament, which are the thickened upper and lower parts of the capsule.
The coracoclavicular ligament from the coracoid process to the inferior surface of the clavicle.
Articular disc
The articular disc of the acromioclavicular joint is incomplete.
Capsule
The fibrous capsule of this joint is attached to the margin of the articular suraces and forms by the thickened surrounding ligaments.
Synovial membrane
The synovial membrane lines the inner surface of the joint capsule.
Nerve supply
The suprascapular nerve.
Movement
Some gliding movement is allowed when the scapula change its position.
Figure1: Shoulder joint.
The Shoulder Joint
Type
It is one of the synovial of ball and socket joints,
Articulation
The shoulder joint is between the head of the humerus (the ball), to the glenoid cavity of the scapula (the socket). The articular surfaces are covered by hyaline cartilage. The cavity of the joint is deepened by the glenoid labrum, which is a fibrocartilaginous rim.
Ligaments
1) The glenohumeral ligaments are three fibrous bands that support the anterior part of the joint capsule.
2) The transverse humeral ligament is another ligament,which forms a bridge across the upper part of the bicipital groove of the humerus between the greater and lesser tuberosities and acts as a retinaculum for the long head of biceps.
3) The coracohumeral ligament is one; extending from the root of the coracoid process to the greater tuberosity and strengthening the capsule superiorly.
4) It also has some accessory ligaments like the coracoacromial ligament,which support the superior part of the capsule. It extends between the coracoid process and the acromion.
Capsule
The capsule is attached to the margin of the articular surface, the capsule extends from the margins of glenoid cavity outside the glenoid labrum and its humeral end is attached to the anatomical neck except inferiorly. The capsule is very loose to permit free movements
Synovial membrane
The synovial membrane lines the interior surface of the capsule and forms a tubular sheath around the tendon of the long head of biceps. There are few openings in the capsule; one is in the anteromedial part through which the synovial membrane descends to form the subscapular bursa. The capsule is strengthen by the rotator cuff. The rotator cuff is formed by subscapularis anteriorly, infraspinatus and teres minor posteriorly and supraspinatus superiorly.
Bursae
Bursae around the shoulder joint include the subscapular bursa, the supraspinatus bursa, the subacromial bursa
Tendons
The biceps tendon passes through the joint capsule.
Nerve supply
It supplied by the axillary and suprascapular nerves.
Movement
The flexion is produced by the clavicular head of pectoralis major, anterior fibres of deltoid, coracobrachialis and biceps brachii. The extension is produced by the posterior fibres of deltoid, latissimus dorsi, teres major and the sternal head of pectoralis major. Abduction passes in two stages, first stage is up to 15 degrees by supraspinatus; the second stage from 15-90 degrees by the lateral fibres of deltoid. Adduction is produced by pectoralis major, latissimus dorsi and teres major. The medial rotation this is produced by pectoralis major, latissimus dorsi, anterior fibres of deltoid and subscapularis. The lateral rotation is produced by infraspinatus, teres minor and posterior fibres of deltoid. Finally, a combination of all of the above movements is called circumduction.
Type
It is one of the synovial of ball and socket joints,
Articulation
The shoulder joint is between the head of the humerus (the ball), to the glenoid cavity of the scapula (the socket). The articular surfaces are covered by hyaline cartilage. The cavity of the joint is deepened by the glenoid labrum, which is a fibrocartilaginous rim.
Ligaments
1) The glenohumeral ligaments are three fibrous bands that support the anterior part of the joint capsule.
2) The transverse humeral ligament is another ligament,which forms a bridge across the upper part of the bicipital groove of the humerus between the greater and lesser tuberosities and acts as a retinaculum for the long head of biceps.
3) The coracohumeral ligament is one; extending from the root of the coracoid process to the greater tuberosity and strengthening the capsule superiorly.
4) It also has some accessory ligaments like the coracoacromial ligament,which support the superior part of the capsule. It extends between the coracoid process and the acromion.
Capsule
The capsule is attached to the margin of the articular surface, the capsule extends from the margins of glenoid cavity outside the glenoid labrum and its humeral end is attached to the anatomical neck except inferiorly. The capsule is very loose to permit free movements
Synovial membrane
The synovial membrane lines the interior surface of the capsule and forms a tubular sheath around the tendon of the long head of biceps. There are few openings in the capsule; one is in the anteromedial part through which the synovial membrane descends to form the subscapular bursa. The capsule is strengthen by the rotator cuff. The rotator cuff is formed by subscapularis anteriorly, infraspinatus and teres minor posteriorly and supraspinatus superiorly.
Bursae
Bursae around the shoulder joint include the subscapular bursa, the supraspinatus bursa, the subacromial bursa
Tendons
The biceps tendon passes through the joint capsule.
Nerve supply
It supplied by the axillary and suprascapular nerves.
Movement
The flexion is produced by the clavicular head of pectoralis major, anterior fibres of deltoid, coracobrachialis and biceps brachii. The extension is produced by the posterior fibres of deltoid, latissimus dorsi, teres major and the sternal head of pectoralis major. Abduction passes in two stages, first stage is up to 15 degrees by supraspinatus; the second stage from 15-90 degrees by the lateral fibres of deltoid. Adduction is produced by pectoralis major, latissimus dorsi and teres major. The medial rotation this is produced by pectoralis major, latissimus dorsi, anterior fibres of deltoid and subscapularis. The lateral rotation is produced by infraspinatus, teres minor and posterior fibres of deltoid. Finally, a combination of all of the above movements is called circumduction.
Figure2: Elbow joint capsule.
The Elbow Joint
Type
It is a synovial hinge joint.
Articulation
The articulation of the elbow joint is between the trochlea and capitulum of the humerus proximally and the trochlear notch of the ulna and upper surface of the head of the radius distally.
Ligaments
1) The radial collateral ligament supporting the joint. Its apex attached to the lateral epicondyle and its base to the annular ligament.
2) The ulnar collateral ligament that composed of 3 bands: Anterior band between the medial epicondyle and the upper part of the medial border of the coronoid process, posterior band between the medial epicondyle and the olecranon process and finally, the transverse band between the coronoid and the olecranon processes of the ulna.
Capsule
The capsule is attached superiorly to the humerus above the coronoid, radial fossae anteriorly and olecranon fossae posteriorly. Inferiorly it attached to the margin of the coronoid process of the ulna and to the annular ligament anteriorly and to the margin of olecranon process of the ulna and the anular ligament posteriorly.
Synovial membrane
The synovial membrane lines the inner surface of the joint capsule.
Nerve supply
The elbow joint is supplied by branches from the median, ulnar, radial and musclocutaneous nerves.
Movement
Flexion of elbow joint is produced by brachialis, biceps brachii and brachioradialis. Extension by triceps brachii and anconeus.
Type
It is a synovial hinge joint.
Articulation
The articulation of the elbow joint is between the trochlea and capitulum of the humerus proximally and the trochlear notch of the ulna and upper surface of the head of the radius distally.
Ligaments
1) The radial collateral ligament supporting the joint. Its apex attached to the lateral epicondyle and its base to the annular ligament.
2) The ulnar collateral ligament that composed of 3 bands: Anterior band between the medial epicondyle and the upper part of the medial border of the coronoid process, posterior band between the medial epicondyle and the olecranon process and finally, the transverse band between the coronoid and the olecranon processes of the ulna.
Capsule
The capsule is attached superiorly to the humerus above the coronoid, radial fossae anteriorly and olecranon fossae posteriorly. Inferiorly it attached to the margin of the coronoid process of the ulna and to the annular ligament anteriorly and to the margin of olecranon process of the ulna and the anular ligament posteriorly.
Synovial membrane
The synovial membrane lines the inner surface of the joint capsule.
Nerve supply
The elbow joint is supplied by branches from the median, ulnar, radial and musclocutaneous nerves.
Movement
Flexion of elbow joint is produced by brachialis, biceps brachii and brachioradialis. Extension by triceps brachii and anconeus.
Figure3: Articulation of the elbow joint.
Figure4: Ulnar collateral ligament.
Figure5: Radial collateral ligament.
Radioulnar joints
Superior radioulnar joint
Type
Synovial, pivot.
Articulations
The articulation is between the head of the radius and the radial notch of the ulna and annular ligament.
Ligaments
The annular ligament is where the head of the radius rotates and is attached to the anterior and posterior margins of the radial notch of the ulna.
Capsule
The joint is enclosed in the capsule of the elbow and shares its synovial membrane.
Synovial membrane
The synovial membrane is continous with the synovial membrane of the elbow joint above and extend to inferior margin of the articular surface of the radius and ulna.
Nerve supply
The superior radio-ulnar joint supplied by the musculocutaneous, median, and radial nerves.
Inferior radioulnar joint
Type
Is synovial pivot joint.
Articulation
The articular surface between the head of the ulna and the ulnar notch of the radius.
Capsule
The capsule is attached to the margins of the articular surfaces but is deficient superiorly.
Articular disc
A triangular shape ligament, its apex is attached to the base of the styloid process of the ulna and its base to the lower margin of the ulnar notch of the radius.
Synovial membrane
The synovial membrane lines the capsule
Nerve supply
It supplied by the deep branch of radial nerve and the anterior interosseous nerve of the median nerve.
Movements of Radioulnar Joints
The radioulnar joints allow rotatory movements around a vertical axis. The rotatory movement are of two types the supination and pronation. The supination is produced by supinator and biceps brachii. The pronation is produced by pronator teres and pronator quadratus. Brachioradialis, flexor carpi radialis and palmaris longus initiate pronation in midprone position.
Superior radioulnar joint
Type
Synovial, pivot.
Articulations
The articulation is between the head of the radius and the radial notch of the ulna and annular ligament.
Ligaments
The annular ligament is where the head of the radius rotates and is attached to the anterior and posterior margins of the radial notch of the ulna.
Capsule
The joint is enclosed in the capsule of the elbow and shares its synovial membrane.
Synovial membrane
The synovial membrane is continous with the synovial membrane of the elbow joint above and extend to inferior margin of the articular surface of the radius and ulna.
Nerve supply
The superior radio-ulnar joint supplied by the musculocutaneous, median, and radial nerves.
Inferior radioulnar joint
Type
Is synovial pivot joint.
Articulation
The articular surface between the head of the ulna and the ulnar notch of the radius.
Capsule
The capsule is attached to the margins of the articular surfaces but is deficient superiorly.
Articular disc
A triangular shape ligament, its apex is attached to the base of the styloid process of the ulna and its base to the lower margin of the ulnar notch of the radius.
Synovial membrane
The synovial membrane lines the capsule
Nerve supply
It supplied by the deep branch of radial nerve and the anterior interosseous nerve of the median nerve.
Movements of Radioulnar Joints
The radioulnar joints allow rotatory movements around a vertical axis. The rotatory movement are of two types the supination and pronation. The supination is produced by supinator and biceps brachii. The pronation is produced by pronator teres and pronator quadratus. Brachioradialis, flexor carpi radialis and palmaris longus initiate pronation in midprone position.
Figure6: Wrist joint ligaments.
Figure7: Articulation of the wrist joint.
Wrist Joint
Type
This joint is synovial, ellipsoid.
Articulations
It articulates with the inferior surface of the lower end of the radius and the articular disc of the inferior radio-ulnar joint proximally, and the scaphoid, lunate and triquetral distally.
Accessory ligaments
1) The anterior ligament is a strong band which extends from the radius to the lunate anteriorly,
2) The posterior ligament is weaker than the anterior and extends from the radius to the lunate posteriorly,
3) The lateral ligament extends from the styloid process of the radius to the scaphoid, and
4) The medial ligament extends from the styloid process of the ulna to the triquetral and pisiform.
Capsule
The capsule surrounds the joint and is attached above to the lower ends of the radius and ulna and below to the proximal row of the carpal bones.
Synovial membrane
The synovial membrane lines the joint capsule and attached to the articular margins.
Nerve supply
It supplied by the anterior interosseous nerve a branch of the median nerve and the deep branch of radial nerve.
Movements
The flexion is produced by flexor carpi ulnaris, flexor carpi radialis and palmaris longus. This movement is assisted by all tendons cross in front of the joint like flexor digitorum superficialis and flexor digitorum profundus. The extension is mainly controlled by extensor carpi radialis longus, extensor carpi radialis brevis and extensor carpi ulnaris. This movement is assisted by all muscles whose tendons cross behind the joint like extensor digitorum, extensor indicis, extensor digiti minimi, and extensor pollicis longus. The abduction is produced by flexor carpi radialis, extensor carpi radialis longus, extensor carpi radialis brevis, abductor pollicis longus, extensor pollicis longus, and extensor pollicis brevis. The adduction is controlled by the flexor carpi ulnaris and extensor carpi ulnaris. Circumduction results from a combination of these movements.
Figure8: Joints of the hand.
Joints of the Hand
Intercarpal joints
Type
The joint is a synovial of plane variety.
Articulations
The articulation is between the carpal bones of each row.
Mid carpal joint
Articulations
The articulation is between the proximal and distal rows of the carpal bones.
Type
Synovial, ellipsoid.
Ligaments
Three types of ligaments anterior, posterior and interosseous ligaments.
Capsule
The capsule surrounds the joint
Synovial membrane
The synovial membrane lines the inner surface and attached to the margin of the articular surface.
Nerve supply
The nerve supply is from the anterior interosseous branch of median nerve, deep branch of radial nerve and deep branch of ulnar nerve.
Movement
Limited amount of gliding movement is allowed at this joint.
Carpometacarpal joints of the medial four fingers
Type
Is a synovial plane joint.
Articulation
The articulation between the trapezoid with the second metacarpal, the capitate articulates with the third metacarpal, and finally the hamate articulates with the fourth and fifth metacarpals.
Movements
Some gliding movement is allowed at this joint.
Figure9: Joints of the hand.
The carpometacarpal joint of the thumb
Type
Is a saddle variety of synovial joint.
Articulation
The articulation is between the distal surface of the trapezium and the proximal surface of the base of the first metacarpal.
Movements
The flexion is produced by the action of flexor pollicis longus and flexor pollicis brevis. The extention is produced by extensor pollicis longus and extensor pollicis brevis. The abduction is produced by abductor pollicis longus and abductor pollicis brevis. The adduction is by adductor pollicis. The opposition is controlled by opponens pollicis.
Type
Is a saddle variety of synovial joint.
Articulation
The articulation is between the distal surface of the trapezium and the proximal surface of the base of the first metacarpal.
Movements
The flexion is produced by the action of flexor pollicis longus and flexor pollicis brevis. The extention is produced by extensor pollicis longus and extensor pollicis brevis. The abduction is produced by abductor pollicis longus and abductor pollicis brevis. The adduction is by adductor pollicis. The opposition is controlled by opponens pollicis.
Intermetacarpal joints
Type
Is a synovial of plane variety.
Articulations
The articulation is between the adjacent bases of the second, third, fourth and fifth metacarpals.
Metacarpophalangeal joints
Type
Is a condylar variety of synovial joints.
Articulation
The articulation is between the heads of the metacarpals and the bases of the proximal phalanges.
Ligaments
The palmar ligament is a strong fibrocartilagenous. The ligaments of the metacarpophalangeal joints are joined to one another by the deep transverse metacarpal ligaments. The medial and lateral collateral ligaments are oblique bands placed at the sides of the joints and extend from the head of the metacarpal bone to the base of the phalanx.
Capsule
The capsule surrounds the joints.
Synovial membrane
The synovial membrane lines the joint capsule.
Movements
The flexion is controlled by the interossei, lumbricals, flexor digitorum superficialis and profundus. The extension is controlled by extensor digitorum, extensor indicis, and extensor digiti minimi. The abduction is performed by the dorsal interossei. The adduction is performed by the palmar interossei.
The interphalangeal joints
Type
It is a hinge variety of synovial joint.
Articulation
The articulation is between the base of one phalanx with the head of the phalanx proximal to it.
Ligaments
The structure of the ligaments is similar to the metacarpophalangeal joints
Capsule
The capsule surrounds the joint.
Movements
The flexion is performed by flexor digitorum superficialis at the proximal interphalangeal joint and flexor digitorum profundus at the distal one. The extension is performed by the interossei and lumbricals.
Figure10: Proximal interphalangeal joint.
