Forearm

Forearm - middle segment of the upper limb. The skeleton of the forearm formed ulna and radius (Fig. 1). Both bones along the entire length of connected interosseous membrane, their proximal ends participate in education elbow; distal radial bone participates in the formation of the wrist joint.
The muscles of the forearm (Fig. 2) are divided into two groups: front - flexors and the model (muscles, turning the palm down) and rear - extensor and arch supports (muscles, turning the palm up). The front group of muscles of the forearm consists of superficial and deep layers. The muscles of this group start from internal namesake humerus. The surface layer are elbow flexor brush, superficial flexor, long Palmar muscle, radial flexor brush, round pronator, preclusive muscle. Deep layer are deep flexor, long flexor thumb and square pronator. Rear group of muscles of the forearm also consists of superficial and deep layers. The muscles of the surface layer start from outside namesake shoulder and proximal part of the fascia of the forearm. This layer are short and long beam extensor brushes, extensor finger extensor small finger, elbow extensor of the brush. In the deep layer are long arm of placing the thumb, short extensor of thumb, long extensor of the thumb, index finger extensor.
The blood supply of the forearm is radial and ulnar artery (the target branch of the brachial artery).
Venous outflow occurs through the subcutaneous and deep veins.
The muscles of the forearm innervated by the branches of the elbow, middle and radial nerves. Ulnar nerve innervates the elbow flexor hand and elbow part of deep flexor, middle - all other flexing muscles of the hand and fingers and the model, the radial nerve - preclusive muscle and all the extensor.craps and the muscles of the forearm

I - beam bone; II - ulna. 1 - olecranon; 2 - block cutting; 3 - coronary process; 4 - cylinder radial bone; 5-the neck of the radial bone; 6 - roughness elbow bones; 7 - the roughness of the radial bone; 8 - interosseous membrane; 9 - styloid process elbow bones; 10 - styloid process of the radial bone.
Fig. 2. Start and attach the muscles to the bones of the right forearm, front and rear (b): 1 and 10 superficial flexor (1 - ulnar side, 10 - beam); d is the long flexor thumb (2 - ulnar side, 8 - beam); 3 and 9 - round pronatura; 4 - shoulder muscles; 5 - deep flexor; 6 - square pronatura; 7 - precaucao muscles; 11 - muscle spinymouse forearm; 12 - biceps muscle shoulder; 13 - elbow muscles; 14 - long muscles of placing the thumb; 15 - short extensor thumb; 16-extensor index finger; 17-the long extensor of the thumb; 18 - elbow flexor wrist.

Forearm (antebrachium) - middle segment of the upper limb.
Anatomy. The proximal border of the forearm forms a circular line, held on 6 cm distal to the internal namesake humerus. Distal border forearm runs along the circular line, held on 3 cm above the skin fold of the wrist. The front and back of the forearm (regio antebrachii ant. et post.) distinguish between a line drawn from the medial namesake the humerus to the styloid process elbow bones, and the other from the lateral namesake to the styloid process of the radial bone.
Forearm has the shape of a flattened from front to back and truncated cone facing on its base up and narrowed from top to bottom. In the front there are two convexity, located, respectively inner and outer halves of the forearm. They are formed by groups of muscles - flexors and extensors of the forearm, hand and fingers. In the bottom half of the front surface of the forearm are deepening, corresponding radial and ulnar furrows of the forearm, and the contours of flexor tendon. With the reduction of muscle in muscular men muscle guidelines forearm becoming more prominent (Fig. 1). On the rear surface of the forearm easily palpation of the radial and ulnar bone, subulate branches and the head of the elbow bones; on the front surface - tendon radial flexor brush (m. flexor carpi radialis), long distal muscles (m. palmaris longus), superficial flexor (m. flexor digitorum superficialis) and elbow flexor brush (m. flexor carpi ulnaris).

external benchmarks forearm Fig. 1. External benchmarks forearm: a - the front surface, b - rear surface. 1 - v. basilica brachii; 2 - Ty m. bicipitis brachii; 3 - v. mediana antebrachii; 4 - m. flexor carpi ulnaris; s - m. palmaris longus; 6 - m. flexor digitorum superficialis; 7 - proximal skin fold wrist; 8 - distal skin fold wrist; 9 - processus styloideus radii; 10 - m. brachioradialis; 11 - m. flexor carpi radialis; 12 - m. brachioradialis; 13 - epicondylus lat.; 14 - m. extensor carpi radialis longus; 15 - m. extensor digitorum; 16 - m. extensor carpi ulnaris; 17 - m. extensor carpi radialis brevis; 18 - m. extensor digiti minimi; 19 - m. abductor pollicis longus; 20 - m. extensor pollicis brevis; 21 - m. abductor digiti minimi; 22 - processus styloideus ulnae; 23 - margo post, ulnae; 24 - v. basilica antebrachii; 25 - m. anconeus; 26 - olecranon; 27 - tendo m. tricipitis brachii.
the arm bone
Fig. 2. The bones of the forearm:
1 - capsula articularis;
2 - trochlea humeri;
3 - cavum articulare;
4 - ulna;
5 - membrana interossea antebrachii;
6 - subtalar distalis;
7 - radius;
8 - chorda obliqua;
9 - tendo m. bicipitis brachii (cut);
10 - lig. anulare radii;
11 - caput radii;
12 - capitulum humeri;
13 - humerus.

The skeleton of the forearm formed elbow (ulna) and radiation (radius) bones that are connected proximal and distal localhostwiki joints (art. radioulnares proximalis et distalis). Between the bones stretched interosseous membrane (membrana interossea) (Fig. 2). With shoulder bone of the forearm is articulated in the elbow joint (see). The distal end of the radial bone is connected to the brush of a wrist (see).
The skin of the anterior surface of the forearm thin, lively, easy going in the folds. Subcutaneous tissue is poorly developed, has a single-layer structure. In the deep layer of fiber are saphenous vein, closely linked to the superficial fascia. On the front there head Vienna and outer skin nerve forearm (v. cephalica et n. cutaneus antebrachii lateralis), lateral - elbow saphenous vein and medial cutaneous nerve of the forearm (v. basilica et n. cutaneus antebrachii medialis). Between them takes place in the middle of the median vein of the forearm (v. mediana antebrachii). Back in the subcutaneous layer are both surface vessels and rear cutaneous nerve of the forearm (n. cutaneus antebrachii post.). Superficial fascia of thinner and own the fascia of the forearm (fascia antebrachii) tighter, especially with the radial side. The processes of the fascia form bed muscles and neurovascular bundle.
The muscles of the forearm are divided into two groups: front containing flexors and the model, and the rear submitted by extensors and the instep. Front muscle group consists of superficial and deep layers. All the muscles of this group, with the exception of the round pronatura and long flexor thumb (mm. pronator quadratus et flexor pollicis longus), start from the internal namesake humerus (epicondylus medialis humeri). The surface layer contains the elbow flexor brush (m. flexor carpi ulnaris), which is attached to a pea-shaped bone (os pisiforme) and forms ulnar edge of the forearm. Knowledge of the topography of this muscle is of great importance when accessing elbow bones, ulnar nerve and ulnar artery. Superficial flexor (m. flexor digitorum superficialis) starts with two heads and occupies almost the entire front surface of the forearm. Its four tendons enter the channel of the wrist. Long Palmar muscle (m. palmaris longus) occupies a middle position and long tendon intertwined in the Palmar aponeurosis. The superficial layer include radial flexor brush (m. flexor carpi radialis), tendon which is fixed to the base II metacarpal bones, as well as a round pronator. Lateral lies preclusive muscle (m. brachioradialis). It starts from the outer edge of the humerus and intermuscular partitions. Knowledge of the topography of this muscle is of great practical importance because of the proximity to her superficial branch of a radial nerve, and the radial artery. Deep layer contains deep flexor (m. flexor digitorum profundus), long flexor thumb (m. flexor pollicis longus) and square pronator (m. pronator quadratus).
Back muscle group consists of superficial and deep layers. All the muscles of the surface layer start from outside namesake shoulder and proximal part of the fascia of the forearm. They are in the following order: closer to the radial edge - short and long beam extensor brush (mm. extensores carpi radiales longus et brevis), finger extensor (m. extensor digitorum), a little further - the extensor small finger (m. extensor digiti minimi), and beyond the elbow extensor brush (m. extensor carpi ulnaris). Among the muscles deep layer closer to the beam direction is long arm of placing your thumb (m. abductor pollicis longus), next to it - short extensor thumb (m. extensor pollicis brevis), and then - long extensor of the thumb (m. extensor pollicis longus) and the index finger extensor (m. extensor indicis). Radiation extensor brush attached to the base II (long) and III (short) metacarpal bones.
Intervals (furrow) between the muscles of the anterior made loose fiber. They are the vessels and nerves of the forearm. Radial groove (sulcus radialis) lies between precaucao muscle and radial flexor brush, where the radial artery (a. radialis) and superficial branch of a radial nerve (ramus superficialis nervi radialis); in the lower third of the forearm artery easily damaged. Median sulcus (sulcus medianus) runs between the radial flexor brush and superficial flexor: this groove is on the bottom quarter of the forearm and contains the distal end of the median nerve (n. medianus), which lies under the fascia of the forearm and can easily be damaged. Ulnar groove (sulcus agent runs between superficial flexor and elbow flexor brush, contains the ulnar artery (a. agent and ulnar nerve (n. ulnaris). The nerve is located on the ulnar side artery and escort her down to the wrist. The close location of the artery and nerve often leads to simultaneous damage, for example if the artery ligation order to stop the bleeding. Isolated damage artery careful selection of the ends of the damaged vessel before bandage and maximum sparing undamaged nerve. Simultaneous damage of the ulnar nerve requires blending epinephrine seams.


Fig. 1-4. Vessels and nerves of the anterior forearm. Fig. 1. The superficial veins and nerves of the skin. Fig. 2. Superficial muscles, vessels and nerves (fascia forearm partially removed and the turned on). Fig. 3. Deep muscles, vessels and nerves (surface muscles partially removed). Fig. 4. The division of the brachial artery, the total discharge of the interosseous artery, the median nerve (in its entirety), deep muscles, vessels and nerves (superficial muscles are removed; m. pronator teres dissected and rejected). 1 - v. basilica; 2 - ramus ant. n. cutanei antebrachii med.; 3 - v. cephalica; 4 - n. cutaneus antebrachii lat.; 5 - skin with subcutaneous fat; 6 - fascia antebrachii; 7 - v. mediana cubiti; 8 - m. pronator teres; 9 - m. flexor carpi radialis; 10 - m. palmaris longus; 11 - m. flexor carpi ulnaris; 12 - n. ulnaris; 13 - a. et vv. ulnares; 14 - m. flexor digitorum superficialis; 15 - n. medianus; 16 - a. et vv. radiales; 17 - ramus superficialis n. radialis; 18 - m. brachioradialis; 19 - m. pronator quadratus; 20 - m. flexor pollicis longus; 21 - m. flexor digitorum profundus; 22 - a. et vv. interosseae ant.; 23 - n. interosseus ant.; 24 - a. interossea communis; 25 - ramus profundus n. radialis; 26 - a. brachialis.




Fig. 1-4. Vessels and nerves of the forearm. Fig. 1. The superficial veins and nerves. Fig. 2. Deep vessels and nerves. Fig. 3. Upper arm artery (polythematic). Fig. 4. Cross-cuts right forearm at the level of the proximal, average and distal thirds. 1 - n. cutaneus antebrachii post.; 2 - n. cutaneus antebrachii lat.; 3 - v. cephalica; 4 - skin subcutaneous fat; 5 - ramus ulnaris n. cutanei antebrachii med.; 6 - fascia antebrachii; 7 - m. supinator; 8 - m. extensor carpi radialis brevis; 9 - m. extensor carpi radialis longus; 10 - m. abductor pollicis longus; 11 - m. extensor pollicis brevis; 12-radius; 13 - a. inlerossea ant. (v et. interossea ant.); 14 - m. extensor pollicis longus (cut); 15 - n. interosseus post.; 16 - m. extensor digitorum; 17 - rami musculares; 18 - a. Interossea post, (v et. interossea post.); 19 - m. extensor carpi ulnaris; 20 - ulna; 21 - ramus superficialis n. radialis; 22 - a. brachialis; 23 - a. recurrens ulnaris; 24 - a. ulnaris (w et. ulnares on the cuts); 25 - a. Interossea communis; 26 - membrana Interossea; 27 - a. radialis (et vv. radiales on the cuts); 28 - tendo musculi bicipitis brachii (turned); 29 - a. recurrens radialis; 30 - m. pronator teres; 31 - m. flexor carpi radialis; 32 - m. palmaris longus; 33 - m. flexor digitorum superficialis; 34 - m. flexor carpi ulnaris; 35 - n. ulnaris; 36 - m. flexor digitorum prof.; 37 - n. medianus; 38 - m. brachioradialis; 39 - ramus dorsalis manus n. ulnaris; 40 - m. pronator quadratus; 41 - m. flexor pollicis longus.

The blood supply of the forearm is radial and ulnar artery, which is the terminal branches of the brachial artery (printing. Fig. 1-4 and figure below. 1-4). Artery widely anastomosis all over, and so tubal one typically does not lead to severe disorders of blood circulation.
Innervation of the forearm occurs due to the median, radial and ulnar nerves. Ulnar nerve innervates the elbow flexor hand and elbow part of deep flexor, middle - all other flexing muscles of the hand and fingers and the model. The radial nerve gives branch to precaucao muscle, and his deep branch, probada m. supinator, get to the back surface of the forearm and innervates all extensor. The skin of the forearm nerviruet medial, lateral and rear nerves of the skin of the forearm.