The compounds in the free part of the upper extremity

The compounds in the skeleton of the free part of the upper limb are the shoulder joint (articulatio humeri), elbow (articulatio cubiti), proximal and distal radioulnar joints (articulatio radioulnaris proximalis and articulatio radioulnaris distalis), wrist (articulatio radiocarpea) and joints of the skeleton hand - srednezapyastnym, carpal -metacarpal, mezhpyastnymi, metacarpophalangeal and interphalangeal joints.

Shoulder joint is formed by connecting the glenoid cavity scapula to the head of humerus. Acetabulum blades surrounded by articular lip (labrum glenoidale), which has a fibrous-cartilaginous structure. Glenoid lip is a relatively small increase (compared with the head of the humerus), the size of the glenoid cavity scapula, and also serves to cushion the possible sharp movements in the joint.

The head of the humerus, in the form of representing a third of the world, provides greater mobility of the joint around the three axes, and also allows a circular motion. The thickness of the cartilage covering the articular surface decreases from center to edge. Joint capsule or bag (capsula articularis), attached to the blade along the outer edge of the labrum, and the humerus on its anatomical cervix, leaving out the joint cavity large and small hillocks of the humerus.

Joint capsule is strengthened ligaments, which are thickened portions of the fibrous layer, the most important is the coracoid ligament-humerus (lig. coracohumerale), passing from the base of the coracoid process. Most of its fibers woven into the capsule, a minority reaches a large tubercle.

In Fig. 31.
Shoulder joint frontal section
1 - joint capsule;
2 - glenoid cavity scapula;
3 - capitellum;
4 - glenoid cavity;
5 - the long head tendon of the biceps;
6 - glenoid lip;
7 - lower volvulus synovial joint

From the outside front and rear of the capsule of the joint adjacent muscles and tendons of the shoulder muscles and shoulder girdle. With nizhnemedialnoy of joint capsule has strengthen her muscles, resulting in high levels of joint nizhnemedialnyh dislocation.

Synovium of the joint (consisting of subsinovialnogo and synovial layers) forms three twisting, expanding the joint cavity. The largest of these - recessus axillaris - is in the lower part of the joint, and is well seen in the reduction of the shoulder.

Elbow - a complex joint formed by the compound in the total capsule humerus with the ulna and radius.

In Fig. 32.
The capsule and ligaments of the shoulder joint
1 - acromion scapula;
2 - coracoid scapula;
3 - Shoulder coracoid ligament;
4 - a large mound humerus;
5 - the long head tendon of the biceps;
6 - joint capsule

At the elbow there are three joints: humeroulnar, brachioradialis and proximal radioulnar.

Ginglymoidal humeroulnar joint block form the humerus and ginglymoidal cut the ulna. Globular head up brachioradialis joint condyle humerus and radial head. The proximal radioulnar joint connects the articular circumference of the radial head with a radial notch of ulna (see "The bones of the forearm").

Humeroulnar joint allows flexion and extension arm at the elbow. Radioulnar joint upper cylindrical shape allows only rotational motion, ie motion around the vertical axis - pronation and supination (rotating beam with a bone with the palm).

In Fig. 33.
The elbow joint elevation
1 - block the humerus;
2 - the joint cavity;
3 - ulnar process;
4 - ginglymoidal notch of ulna;
5 - coronoid process of ulna

Fibrous capsule of the elbow fibers are attached to the periosteum of the humerus in front of the beam and crown pits, in the back of the ulnar fovea, sides of the base of the two epicondyles. On the bones of the forearm joint capsule is fixed at the edges of the articular cartilage on the ulnar and the radial is attached to her neck. Behind the elbow joint capsule less sturdy.

In Fig. 34.
The elbow joint, front view
1 - joint capsule;
2 - ulnar collateral ligament;
3 - head humeral condyle;
4 - Block humerus;
5 - coronoid process of ulna;
6 - head of the radius;
7 - the interosseous membrane of forearm

The joint is strengthened beam (lig. collaterale radiale) and second (lig. collaterale ulnare) collateral ligaments, which extend from the epicondyles of the humerus ulna.

The proximal radioulnar joint is formed by radial notch of ulna, located on the lateral side of its upper epiphysis, and the radial head. The annular ligament of the radius (lig. annulare radii), attached to the ulna, radius covers the cervix, thus fixing the connection.

In Fig. 35.
Barkow's ligament
1 - joint capsule;
2 - ulnar collateral ligament;
3 - radial collateral ligament;
4 - annular ligament of radius

The distal radioulnar joint rotary, cylindrical in shape. Forming its ulnar notch radial articular head circumference and ulna are separated by cartilaginous articular disc of triangular shape. The peak of the disc attached to a subulate appendage head of ulna, and the base - to the ulnar cutting out the radius. Joint allows reduction and removal of brush (its motion in the sagittal plane).

In Fig. 36.
Joints and ligaments back of the brush surface
1 - ulna;
2 - radial bone;
3 - distal radioulnar joint;
4 - articular disc;
5 - wrist joint;
6 - srednezapyastny joint;
7 - intercarpal joints;
8 - carpal-metacarpal joints;
9 - mezhpyastnye joints;
10 - metacarpals

Radiocarpal joint are elliptical, connects the lower epiphysis of the radius and articular disc (discus articularis) ulna bones with proximal row wrist. As the head of the ulna is located at some distance from the wrist, the free space is filled with cartilage (fibrocartilago triangularis), the articular surface of an employee for a three-sided dice. Carpal articular surface of the radius and the distal articular surface of the articular disk form a hollow wrist and his head are the navicular, lunate, and triangular carpal bones. Approximately 40% of the cartilage has a slit through which the wrist joint can communicate with the lower radioulnar.

Motion in the joints occur around two axes: the brush can be moved in the sagittal plane (in the direction of radial or ulnar), as well as bend and bends, revolving around the frontal axis wrist.

Reinforce the joint capsule palmar radiocarpal ligament (lig. radiocarpale m. palmare), radiocarpal ligament back of the hand (lig. radiocarpale m. dorsale), ulnar and radial collateral ligaments (lig. collaterale carpi ulnare and lig. Collaterale carpi radiale).

In the brush, there are six kinds of compounds: srednezapyastny, intercarpal, carpal-metacarpal, mezhpyastnye, metacarpophalangeal and interphalangeal joints.

Srednezapyastny joint (articulatio mediocarpalis), having S-shaped articular gap separates the bones of the distal and proximal (except pisiform bone) series wrist. The joint is functionally integrated with the wrist and allows some degree of freedom to expand the latter. Movement in the joint srednezapyastnom occur around the same axes as in the wrist. Both joints reinforced with the same chords.

Intercarpal joints (articulationes intercarpales) interconnected side surfaces of the carpal bones of the distal row, and strengthened the connection of radiant carpal ligament (lig. carpi radiatum).

Carpal-metacarpal joints (articulationes carpometacarpales) connect the base of the metacarpal bones with the bones of the distal carpal series. Except for the articulation with the trapezium bone of the metacarpal bone of a large (I) finger, carpal-metacarpal all joints are flat, their degree of mobility is low. The compound is a trapezoid and trapezoid I metacarpal bone and provides a significant mobility of the thumb. Capsule carpal-metacarpal joint reinforced palms and rear-carpal-metacarpal ligaments (ligg. carpometacarpea palmaria et dorsalia).

In Fig. 37.
Bundles of the wrist joint and hand joints rear surface
1 - ulnar collateral ligament wrist;
2 - radial collateral ligament wrist;
3 - wrist band back of the hand;
4 - dorsal carpal-metacarpal ligament;
5 - dorsal metacarpal ligament;
6 - metacarpal bone;
7 - collateral ligaments;
8 - metacarpophalangeal joint;
9 - the lateral ligament knuckle
In Fig. 38.
Ligaments and joints wrist wrist palmar surface
1 - ulnar collateral ligament wrist;
2 - palmar radiocarpal ligament;
3 - radial collateral ligament wrist;
4 - radiant wrist ligament;
5 - palmar carpal-metacarpal ligament;
6 - palmar metacarpal ligament;
7 - metacarpal bone;
8 - collateral ligaments;
9 - metacarpophalangeal joint of the finger V;
10 - deep transverse metacarpal ligament;
11 - lateral ligament knuckle

Mezhpyastnye joints (articulationes intermetacarpales) flat, with low mobility. They shall be grounds for lateral articular surfaces of metacarpal bones (II-V), stronger palmar metacarpal ligaments and rear (ligg. metacarpea palmaria et dorsalia).

Metacarpophalangeal joint (articulationes metacarpophalangeales) are elliptical, connect the base of proximal phalanx and the head of the metacarpal bones, fortified collateral (side) ligaments (ligg. collateralia). These joints allow for movement around two axes - in the sagittal plane (abduction and bringing a finger) and around the frontal axis (flexion-extension).

Interphalangeal joints (articulations interphalangeales) ginglymoidal, connect the head upstream of the phalanges with bases downstream. Interphalangeal joints provide flexion-extension of fingers and strengthened collateral ligament.

The heads of metacarpal bones articulate with each other have no connection, they are connected (with the palm side) deep transverse metacarpal ligament (lig. metacarpeum transversum profundum).





List of Abbreviations

a., aa. — arteria, arteriae (artery, the artery)

lig., ligg. — ligamentum, ligamenta (ligament, the ligaments)

m., mm. — musculus, musculi (muscle, the muscle)

n., nn. — nervus, nervi (nerve, the nerve)

r., rr. — ramus, rami (branch)

s. — seu (or)

v., vv. — vena, venae (vienna)