Within the shoulder girdle and the free upper limb, the muscles are limited by a number of anatomical and topographic formations (pits, cavities, openings, canals and grooves), in which vessels and nerves pass, which is of great practical importance.
Axillary fossa, fossa axillaris - located in regio axillaris. With the arm abducted, the contours of the muscles limiting the fossa are visible through the skin: in front - the lower edge, m. pectoralis major, posterior (medial) - lower edge, m. latissimus dorsi and m. teres major, medially - by a conventional line connecting the edges of the named muscles on the chest, and from the side (laterally) - by a line connecting these edges on the inner surface of the shoulder. By removing the skin, subcutaneous tissue, lymph nodes, and axillary fascia of the axillary fossa, the axillary cavity is exposed.
Axillary cavity, cavum axillare - located deeper than the axillary fossa. It has the shape of a four-sided pyramid, the base of which faces down and to the side, and the “top” faces up and in the middle. The base of the axillary cavity opens with a wide opening - the lower aperture, apertura inferior, the boundaries of which correspond to the boundaries of the fossa axillaris. Superior aperture, apertura superior, located between the collarbone (in front); with the first rib and the upper edge of the scapula (back), it connects the inguinal cavity with the neck area.
Cavum axillare is limited by four walls: anterior - mm. pectoralis major et minor-, posterior - mm. latissimus dorsi, teres major, subscapularis; medial - m. serratus anterior, lateral - humerus with m. coracobrachialis and short head m. biceps brachii.
Cavum axillare is filled with fatty tissue, in which blood vessels, nerves and lymph nodes are located. The anterior wall of the axillary cavity is divided into three triangles:
1) submammary, trigonum subpectoral - limited by the lower edge mm. pectoralis major et minor,
2) clavipectoral, trigonum clavipectorale - formed by the clavicle and the upper edge of m. pectoralis minor;
3) chest, trigonum pectorale - answers m. pectoralis minor.
On the posterior wall of the axillary cavity there are two openings: three-sided and four-sided: three-sided opening, foramen trilaterum, limited to: the upper wall - m. subscapularis; lower - m. teres major, lateral - caput longum m. triceps brachii; quadrilateral opening, foramen quadrilaterum, limited: upper wall - m. subscapularis; lower - m. teres major, medial - caput longum m. triceps brachii; lateral - surgical neck, os humerus.
Through the three-way hole passes a. circumflexa scapulae, and through the quadrilateral - a. circumflexa humeri posterior et n. axillaris.
Radial nerve canal, canalis nervi radialis (brachial-muscular canal, canalis humeromuscularis), - located on the posterior surface of the shoulder, formed by sulcus n. radialis and triceps brachii muscle, m. triceps brachii. The canal has a spiral course; the radial nerve, deep brachial artery and veins pass through it. On the front surface of the shoulder between m. brachialis and m. biceps brachii there are two grooves: sulcus bicipitalis medialis et lateralis.
Cubital fossa, fossa cubitalis - located in front of the elbow joint in the anterior ulnar region; it is limited: on the side - m. brachioradialis and
average - m. pronator teres, the bottom of the fossa and the upper edge forms m. brachialis. There are two grooves in the ulnar fossa: the lateral biceps, sul. bicipitalis lateralis, and medial, sul. bicipitalis medialis. The lateral groove is limited from the outside by the brachioradialis muscle, and the medial groove by the brachialis muscle. The medial ulnar groove is limited laterally by the pronator teres, and medially by the brachialis muscle. The brachial artery, the veins that accompany it, and the median nerve pass through the cubital fossa. Between the muscles of the forearm on the anterior surface there are three grooves:
1) ulnar groove, sulcus ulnaris - limited to m. flexor carpi ulnaris and m. flexor digitorum superficial, it contains the ulnar nerve, artery and veins;
2) radial sulcus, sulcus radialis - limited to m. brachioradialis and m. flexor carpi radialis, it contains the nerve of the same name, artery and veins;
3) median sulcus, sulcus medianus - limited m. flexor carpi radialis and rn. flexor digitomm superficial, the median nerve passes through it, n. medianus. In the area of the wrist joint there is the carpal canal, canalis carpi and canalis carpi ulnaris, s. spatium interaponeuroticum Guyoni, and also pass through two synovial sheaths: for the tendons of m. flexor digitorum superficial etprofundus and tendons m. flexorpollicis longus.
Carpal channel, canalis carpi - located above the distal row of carpal bones. Its posterior wall is formed by the ossa trapezium, trapezoideum, saritatum and ligaments that strengthen the joints between them. The anterior wall of the canal is the retinaculum flexorum, which extends over the carpal groove. The average length of the canal is 2.5 cm, width 2-2.5 cm, and depth 1.3-1.5 cm. The contents of the metacarpal canal are the flexor tendons of the fingers, located in the synovial sheaths (common synovial flexor sheath and long tendon sheath). flexor thumb). In the canal in the synovial vagina, the median nerve, n. medianus.
Anatomical tobacco plant - is a triangular-shaped space, which is limited in front and outside by m. extensor pollicis brevis and m. abductor pollicis longus, and behind - by the tendon of m. extensor pollicis longus. The bottom of the anatomical tobacco cup is formed by the scaphoid and trapezoid bones. Its apex is the basis os metacarpalis (I), and its base is the outer edge of the radius.
The depression with the magical name Fossa axillaris can be compared to a modern automobile interchange in an advanced metropolis. Bundles of large vessels, important nerves, lymph nodes, and muscle ligaments intertwine here.
This axillary fossa is one of the busiest intersections in the human body. Fossa axillaris is a magnificent example of the architecture of the human body with its complex communications and functional diversity.
Pit, depression, cavity: what's the difference?
First you need to understand the terms. The pit and the depression (the same Fossa axillaris) are one and the same. This is a superficial depression visible to the naked eye between the inner surface of the shoulder and the lateral surface of the chest. It has another name - the axillary cavity. The axillary fossa is clearly visible when the arm is raised.
There is another term. This is the axillary cavity (axilla, or armpit), which is located deeper, under the fossa: if you cut the skin in the area of the fossa, you can get into the cavity.
The word “armpit” needs special clarification. This name is not very trusted and is often considered folk slang. Completely in vain, because the armpit is the official name for the same axillary cavity. This is a single continuous word from the Russian dictionary; it can be confidently used with prepositions: “in the armpit”, “under the armpit”, etc.
It should be noted that medical sources describe the above terms differently. This overview provides general basic information about axillary area, therefore there is no fundamental difference between the terms “pit”, “depression” and “cavity” here.
Communication hub of the highest category
A communication hub is a concept from modern logistics that perfectly describes the functional purpose of Fossa axillaries. A multicomponent neurovascular bundle, composed of large main vessels - the axillary artery, axillary vein and seven branches of the powerful nerve plexus from the brachial ganglion, will be stretched through this fossa. Numerous lymphatic ducts run along the accompanying paths in the immediate vicinity. The lymph nodes in the armpit are scattered in huge numbers - they are located in the fatty tissue. Their number is determined by the most important function - the protection of lymphatic fluid circulating in the upper third chest, and this is nothing more than the top Airways- one of the most vulnerable organs to various types of infections.
The contents of the armpit can be divided into the following components:
- Arteries - the main axillary artery with its branches.
- Veins - the main axillary vein with its tributaries.
- Nerves in the form of a brachial plexus, consisting of three bundles: posterior, lateral, median.
- Lymphatic vessels and five groups
- Fiber, consisting mainly of adipose tissue.
Protection and safety
The localization of such a significant neurovascular bundle suggests high degree safety of this area. The armpit is perfectly protected. Perhaps this is the most protected external area in the human body.
All four walls of the axillary fossa are formed by groups of shoulder and pectoral muscles and their muscular fascia:
- Front wall It is represented by the clavipectoral fascia and two pectoral muscles - major and minor, which are attached to the upper edge of the shoulder and the front side of the upper chest. Thus, both pectoral muscles perfectly protect the axillary vessels and nerves.
- Back wall formed from the latissimus dorsi, subscapularis, infraspinatus and supraspinatus, as well as the round muscles: minor and major.
- Medial wall formed by the serratus anterior muscle, attached to the lateral wall of the chest up to the 5th rib.
- Lateral wall formed by the coracobrachialis muscle, attached to the inner surface of the shoulder.
Muscle pyramid
When you raise your arm, the armpit has the shape of a quadrangular pyramid with the four walls described above. A pyramid has a top and a bottom:
- The apex is located in the space between the collarbone and the first rib. It is through it that vessels and nerves enter the axillary cavity in the form of a bundle.
- The bottom, or base of the pyramid, is represented by adjacent muscles. It is formed by the common fascia, which, in turn, is formed from the fascia of the adjacent muscles of the back: the pectoralis major and the latissimus.
Thus, the muscles of the axillary fossa create a distinct “geography” for it and provide excellent external protection.
Arteries
The axillary artery (Arteria axillaris) is one of the most important main vessels in the arterial network into which the subclavian artery passes. Then it passes, in turn, into the brachial artery. The superior segment of the axillary artery runs from the collarbone between the second and third ribs. Here it is perfectly protected (Musculus subclavius). In the same segment, two branches depart from the axillary artery: the thoracoacromial artery, which carries blood to the shoulder joint and deltoid muscle, and the superior pectoral artery, which supplies the two pectoral muscles: minor and major.
The lateral thoracic artery (A. Thoracica lateralis) is another branch that begins in the middle segment of the axillary artery. Its function is to supply blood to the axillary fossa itself, its lymph nodes and the superficial layers of the mammary glands.
In the third, lower segment, powerful branches depart from the artery: the subscapular and dorsal arteries of the chest, the circumflex artery of the scapula. All of them take part in the anastomoses of the vessels of the neck and upper extremities.
Vienna
The axillary vein is formed by the confluence of two brachial veins. In turn, it turns into In its upper part, the axillary vein lies in close proximity to the axillary artery in a common vascular canal. Below - in the middle and lower sections - it is separated from the artery by the nerves of the forearm.
Under the collarbone, a powerful tributary flows into the vein - the lateral saphenous vein of the arm; above - the medial saphenous vein of the arm. Most people are familiar with the location of this vein, even those who have nothing to do with medicine: intravenous injections or blood sampling from a vein are most often made in the Vena basilica - in the area of the elbow joint on the inside.
Nerves
All nerve trunks of the axilla are divided into short (for example, and long branches (for example, the median nerve). Functionally, the short branches innervate the muscles and bones of the shoulder girdle, while the long ones are responsible for the upper limb. The nerve bundle of the axillary fossa is formed at the level of the middle section of the axillary artery.
The brachial plexus, in the form of three nerve bundles, is the beginning of the powerful nerves of the upper limb. Two nerves emerge from the lateral bundle: the median (medial) and the musculocutaneous. From the median bundle - the ulnar nerve and part of the posterior one - the radial and axillary nerves.
The subscapular nerves can vary in number from three to seven; they originate from the cervical vertebrae and run to innervate it, as well as the teres and latissimus muscles.
Lymphatic network
The lymph nodes in the armpit are often rated as the most troublesome glands in the human body. And indeed, they cause a lot of problems: of all the nodes, they are the ones that most often become inflamed. The reason for this is the structural features of the axillary fossa (a “logistics hub” consisting of many components) and problems in the mammary glands, chest and upper extremities - areas of the body that are innervated and supplied with blood from nearby vessels and nerves.
Lymph nodes are scattered and, depending on their location, are divided into five groups: lateral, central, thoracic, subscapular, apical. The size of the axillary lymph nodes also depends on the location, on average they are no more than 1.0 mm.
Part I. TOPOGRAPHY OF THE UPPER LIMB
1. AXILLAR CAVITY
1.1. LOCATION OF THE AXILLAR CAVITY
Axillary fossa- this is the depression between the lateral surface of the chest and top part shoulder, opening when it is abducted (Fig. 1). The axillary fossa is limited by:
anterior skin fold covering the edge of the pectoralis major muscle;
posterior fold of skin covering the latissimus dorsi muscle.
^
Rice. 1. Skin relief of the axillary fossa:
1 – axillary fossa, 2 – edge of the pectoralis major muscle, 3 – edge of the latissimus muscle;
axillary cavity, cavum axillare – this is the intermuscular space that opens after removal of skin, fascia and fatty tissue from the area of the axillary fossa (Fig. 2). The cavity has a pyramidal shape and contains:
four walls: anterior, posterior, medial and lateral;
two holes: upper aperture and lower aperture
Rice. 2. Axillary cavity (A), its upper (B) and lower (C) apertures (highlighted in black and white dotted line). Front view.
1 – serratus anterior muscle (medial wall of the axillary cavity), 2 – pectoralis major muscle (cut off), 3 – clavicle, 4 – pectoralis minor muscle (cut off), 5 – subscapularis muscle (posterior wall of the axillary cavity), 6 – coracobrachialis muscle, 7 – biceps brachii (both muscles form the lateral wall of the cavity), 8 – triceps brachii, 9 – latissimus dorsi
Inferior aperture of the axillary cavity limited:
in front - the edge of the pectoralis major muscle;
behind – the edge of the latissimus dorsi muscle;
medially - a conditional line connecting the edges of the pectoralis major and latissimus muscles along the line of the third rib;
laterally – the coracobrachialis muscle and the humerus;
from below - closed by axillary fascia
Superior aperture of the axillary cavity limited:
bottom – 1st rib;
above – collarbone;
behind - the upper edge of the scapula.
Vessels and nerves pass through the upper aperture into the axillary cavity: the axillary artery and vein and the trunks of the brachial plexus.
^ 1.2. WALLS OF THE AXILLAR CAVITY
The medial wall is formed:
serratus anterior muscle
The lateral wall is formed:
coracobrachialis muscle
biceps brachii muscle;
The back wall is formed:
latissimus dorsi muscle;
teres major muscle;
subscapularis muscle;
Front wall(see Fig. 3, which shows a sagittal section drawn through the outer third of the clavicle) is formed:
pectoralis major muscle
pectoralis minor muscle,
deep layer of the pectoral fascia.
Rice. 3. Sagittal section of the axillary cavity
A – anterior wall of the cavity, B – posterior wall
1 - clavicle, 2 - clavipectoral fascia, 3 - pectoralis minor muscle, 4 - pectoralis major muscle, 5 - axillary fascia, 6 - latissimus dorsi muscle, 7 - teres major muscle, 8 - teres minor muscle, 9 - infraspinatus muscle , 10 – subscapularis muscle, 11 – supraspinatus muscle, 12 – neurovascular bundle of the axilla, 13 – trapezius muscle
^ 1.3. SEPARATE TOPOGRAPHANATOMICAL FORMATIONS ON THE WALLS OF THE AXILLAR CAVITY
On the anterior wall of the axillary cavity There are three triangles related to the topography of blood vessels and nerves: the clavipectoral, thoracic and inframammary triangles (Fig. 4).
These triangles are limited:
A. Clavipectoral triangle:
Above - collarbone
Below - the upper edge of the pectoralis minor muscle;
From above - the upper edge of the pectoralis minor muscle
Below - the lower edge of the pectoralis minor muscle (corresponds to the contours of this muscle);
. Submammary triangle:
From above - the lower edge of the pectoralis minor muscle
Below - the lower edge of the pectoralis major muscle.
Rice. 4. Triangles of the anterior wall of the axilla. A – clavipectoral triangle, B – thoracic triangle, C – inframammary triangle
1 – pectoralis major muscle (opened), 2 – clavicle, 3 – pectoralis minor muscle
^ On the posterior wall of the axillary cavity two openings are formed through which blood vessels and nerves also exit. These are three-sided and four-sided holes (Fig. 6):
^
T
Rice. 5. Openings in the posterior wall of the armpit. A – three-sided hole, B – four-sided hole
1 – infraspinatus muscle, 2 – teres minor, 3 – head humerus, 4 – surgical neck of the humerus, 5 – long head of the triceps brachii muscle, 6 – teres major muscle
three-sided hole (A) is limited:
Above - edge of the teres minor muscle
Below - the edge of the teres major muscle;
Laterally – the long head of the triceps brachii muscle;
The four-sided hole (B) is limited:
Medially – the long head of the triceps brachii muscle;
Laterally – the surgical neck of the humerus;
From above - the edge of the teres minor muscle;
Bottom - edge of the teres major muscle
2.1. MEDIAL GROOVE OF THE SHOULDER
M 
edial groove of the shoulder, sulcus bicipitalis medialis
(Fig. 6), is located on the medial surface of the shoulder, starting from the lower border of the axillary cavity and ending in the ulnar fossa.
The medial groove of the shoulder is limited by:
In front - the biceps brachii muscle;
Posteriorly – the triceps brachii muscle;
On the lateral side – the coracobrachialis and brachialis muscles.
Rice. 6. Medial groove of the shoulder (highlighted in black and white dotted line).
A – medial groove of the shoulder, B – axillary cavity, C – ulnar fossa.
1 - biceps brachii muscle, 2 - coracobrachialis muscle, 3 - trilateral foramen, 4 - lower border of the axillary cavity, 5 - triceps brachii muscle (long head), 6 - medial head of the same muscle, 7 - brachialis muscle
^ 2.2. BRACHEMUSCULAR CANAL
P 
lechemomuscular canal (radial nerve canal), canalis humeromuscularis, located in the posterior region of the shoulder, going around the humerus in a spiral. This channel has: an inlet, walls and an outlet (Fig. 7).
^ Channel inlet formed between the inner edges of the medial and lateral heads of the triceps brachii muscle ;
Outlet located in the lateral intermuscular septum of the shoulder, between the brachialis muscle and the initial section of the brachioradialis muscle.
Channel walls are formed:
groove of the radial nerve on the diaphysis of the humerus;
lateral head of the triceps brachii muscle;
medial head of the triceps brachii muscle.
Rice. 7. Brachial muscular canal with open walls (highlighted by a dotted line)
1 – long head of the triceps brachii muscle, 2 – medial head, 3 – lateral head (cut and turned away), 4 – inlet of the brachiomuscular canal, 5 – brachial canal and its neurovascular bundle, 6 – outlet of the canal, 7 – medial intermuscular septum, 8 – brachioradialis muscle
Additionally, the location of the medial groove of the shoulder and the brachiomuscular canal can be viewed in Figures 8 and 9.
^
Rice. 8. The location of the medial groove of the shoulder (the bottom of the groove is indicated by a dotted line) and the neurovascular bundle in it. Inside view.
1 – bottom of the medial groove of the shoulder, 2 – biceps brachii muscle, 3 – coracobrachialis muscle, 4 – heads of the triceps brachii muscle, 5 – vessels and nerves
^
Rice. 9. Horizontal cut through the middle third of the shoulder. The medial groove and brachial canal are highlighted with dark shading.
1 – medial groove of the shoulder and the vessels and nerves lying in it; 2 – biceps brachii, 3 – brachialis, 4 – triceps brachii, 5 – brachial canal
cubital fossa, fossa cubitalis, located in front above the elbow joint and is limited by three muscles (Fig. 10):
from above – the brachialis muscle;
medially – pronator teres.
1 – biceps brachii, 2 – brachioradialis, 3 – brachialis, 4 – pronator teres
^If excised the tendon of the biceps brachii and pronator teres, and then move the muscles apart, then two grooves are found along the edges of the cubital fossa: the medial ulnar groove and the lateral ulnar groove (Fig. 11).
^ Medial ulnar groove , which is a continuation of the medial groove of the shoulder, is limited:
medially – pronator teres and medial epicondyle of the shoulder;
laterally – by the brachialis muscle;
Lateral ulnar groove, which is, as it were, a continuation of the brachiomuscular canal (in this groove lies the radial nerve emerging from the canal), limited: 
Rice. 11. Furrows of the ulnar fossa (highlighted with a white dotted line). A – lateral ulnar groove, B – medial ulnar groove.
1 - biceps brachii muscle, 2 - brachialis muscle, 3 - brachioradialis muscle, 4 - supinator muscle, 5 - medial groove of the shoulder and its contents, 6 - pronator teres (cut off), 7 - medial epicondyle of the shoulder, 8 - flexor digitorum superficialis
^ 4. MUSCULAR GROOVES OF THE FOREARM
In the anterior region of the forearm, three intermuscular grooves are distinguished, which are also important for describing the topography of blood vessels and nerves: the radial groove, the median groove and the ulnar groove (Fig. 12).
Radial groove, sulcus radialis, is limited to:
laterally – by the brachioradialis muscle;
medially – flexor carpi radialis;
Median sulcus, sulcus medianus, is limited to:
laterally – flexor carpi radialis;
medially – flexor digitorum superficialis;
Ulnar groove, sulcus ulnaris, is limited to:
laterally – flexor digitorum superficialis;
medially - flexor carpi ulnaris
Rice. 12. Grooves on the anterior surface of the forearm. A – radial groove, B – median groove, C – ulnar groove (highlighted with dark shading).
1 – cubital fossa, 2 – brachioradialis, 3 – pronator teres, 4 – flexor carpi radialis, 5 – palmaris longus, 6 – flexor digitorum superficialis, 7 – flexor carpi ulnaris
^ 5. TOPOGRAPHANATOMICAL ELEMENTS OF THE HAND
5.1. ANATOMICAL TOBACTER BOX
T 
This is the name given to the triangular depression located between the styloid process of the radius and the base of the 1st metacarpal bone (see Fig. 13). It got its name from the fact that snuff was poured onto this place before sucking it into the nose.
The anatomical snuffbox is limited by the tendons of the short (2) and long (4) extensor pollicis and the retinaculum tendons (7).
^
Rice. 13. Anatomical snuff box (highlighted by dotted line)
1 – base of the first metacarpal bone, 2 – tendon of the short extensor pollicis, 3 – radial artery at the bottom of the snuff box, 4 – tendon of the long extensor pollicis, 5 – interosseous muscles, 6 – superficial branch of the radial nerve, 7 – extensor retinaculum
^ 5.2. WRIST CHANNEL
Carpal channel(Fig. 14) serves to pass the finger flexor tendons onto the hand. It is formed over the palmar surface of the carpal bones and is limited to:
from the inside - by the bones of the wrist;
externally – by the retinaculum of the flexor tendons;
laterally – the tubercles of the scaphoid and trapezium bones;
medially – hook of the hamate
Rice. 14. Carpal tunnel. Horizontal section at the level of the trapezium bone
1 – retinaculum of the flexor tendons, 2 – common synovial sheath of the flexor tendons of the fingers, 3 – tendons of the superficial digital flexor, 4 – tendons of the deep flexor of the fingers, 5 – tendon of the long flexor pollicis, 6 – tendon of the flexor carpi radialis, 7 – trapezius bone, 8 – digital extensor tendon, 9 – hamate bone, 10 – flexor carpi ulnaris tendon
^ 5.3. PALMAR APONEUROSIS AND CELLULAR SPACES OF THE PALM
The palmar aponeurosis (Fig. 15) is a thickened native fascia of the hand, which has acquired a tendon structure to strengthen the skin of the palm. It has the shape of a triangle, the apex of which is located in the region of the flexor tendon retinaculum (where the palmaris longus tendon is woven into it), and the base faces the fingers. The aponeurosis is formed by longitudinal and transverse fibers.
Longitudinal fibers are combined into 4 bundles, heading to the bases of the II - V fingers. In the distal part of the aponeurosis there are transverse bundles. In the spaces between the longitudinal and
^
Rice. 15. Palmar aponeurosis (A).
1 – muscles of the eminence of the little finger, 2 – muscles of the eminence of the thumb, 3 – longitudinal bundles of the palmar aponeurosis, 4 – transverse bundles, 5 – commissural openings
transverse bundles form commissural openings. These holes are filled with fatty tissue that protrudes under the skin in the form of pads. Through these holes inflammatory process can spread into the deep cellular spaces of the hand.
Two fascial septa extend inward from the palmar aponeurosis - lateral and medial.
^ Lateral intermuscular septum attaches to the third metacarpal bone;
Medial intermuscular septum attaches to the fifth metacarpal bone.
The medial bed (hypotenar bed) is limited by:
own fascia of the palm;
V metacarpal bone;
medial intermuscular septum
The lateral bed (thenar bed) is limited by:
own fascia of the palm;
deep fascia and II metacarpal bone;
lateral intermuscular septum;
The middle bed is limited:
externally – palmar aponeurosis;
from the inside - by the deep fascia of the palm;
laterally – by the lateral intermuscular septum;
medially - medial intermuscular septum.
The medial bed of the palm contains the finger flexor tendons and the lumbrical muscles. These structures divide the bed into two cellular fissures: superficial (subgaleal) and deep (subtendinous).
The superficial fissure of the median bed of the palm is limited by:
Externally – palmar aponeurosis;
From the inside - by the tendons of the finger flexors;
The deep gap is limited:
Externally – by the finger flexor tendons and lumbrical muscles;
From the inside - deep palmar fascia covering the metacarpal bones and interosseous muscles
Rice. 16. Cellular spaces of the palm. Horizontal cut.
A – medial fascial bed (hypothenar space);
B – median fascial bed:
8 – superficial cellular fissure of the median fascial bed (highlighted by round dots),
^ 15 – deep cellular fissure of the median fascial bed (highlighted by dotted filling);
B – lateral fascial bed (thenar space).
1 - medial intermuscular septum, 2 - lateral intermuscular septum, 3 - superficial and deep flexor tendons of the fingers to the little finger (in the synovial sheath), 4 - lumbrical muscles, 5 - flexor tendons to the fourth finger, 6 - palmar aponeurosis, 7 - flexor tendons to the third finger; 9 – flexor tendons to the second finger; 10 – tendon of the long flexor of the first finger in the synovial sheath, 11 – muscles of the eminence of the thumb, 12 – metacarpal bones, 13 – interosseous muscles, 14 – extensor tendons of the fingers, 16 – deep palmar fascia.
^ 5.4. SYNOVIAL VAGINA OF THE FINGER FLEXOR TENDONS
Synovial sheaths are a muscle accessory and are designed to eliminate friction where tendons pass through narrow osteofibrous canals. They are closed bags formed by two synovial layers wrapped around the tendons (Fig. 17).
P 
Knowledge of the topography of the synovial sheaths of the finger flexors is of practical importance, since they can become infected through microtraumas of the hand. When an infection enters the vagina, a purulent-inflammatory process develops in its cavity, spreading over its entire length and capable of breaking further into the deep cellular spaces of the palm and forearm.
The following synovial sheaths are distinguished on the hand (Fig. 18):
^ Common flexor sheath , located in the carpal tunnel and surrounding the tendons of the superficial and deep digital flexors. The proximal wall of this vagina faces the deep cellular space of the forearm, and the distal wall faces the median fascial bed;
^ Flexor pollicis longus sheath , also continuing to the forearm. In a certain percentage of cases it communicates with the common flexor sheath;
Tendon sheaths of fingers II–IV. These vaginas are isolated, extending only to the length of the fingers. The proximal walls of these vaginas border the median fascial bed;
Tendon sheath of the fifth finger. This vagina almost always communicates with the common flexor sheath.
T 
Thus, as follows from consideration of the anatomy of the vagina, the most dangerous is the inflammatory lesion of the vaginas of the 1st and 5th fingers, because along these sheaths the infection can easily spread to the deep cellular spaces of not only the palm, but also the forearm.
^
Rice. 18. Synovial sheaths of the digital flexor tendons.
1 – tendon of the deep flexor digitorum, 2 – tendon of the superficial flexor digitorum, 3 – flexor retinaculum, 4 – common synovial sheath of the flexors, 5 – sheath of the fifth finger, 6 – sheath of the long flexor of the first finger, 7 – sheath of the II – IV fingers, 8 – muscles of the eminence of the first finger, 9 – muscles of the eminence of the little finger
Part II. TOPOGRAPHY OF THE LOWER LIMB
^ 1. FEMORAL TRIANGLE
Femoral triangle, trigonum femorale, is formed in the upper third of the thigh on its anterior surface (Fig. 19). It is limited to the following structures:
Above – inguinal ligament;
Laterally – by the sartorius muscle;
Medially – long adductor muscle.
Rice. 19. Borders of the femoral triangle (highlighted by a dotted line) and subcutaneous cleft (skin and subcutaneous tissue removed to the fascia lata)
1 - inguinal ligament, 2 - fascia lata, 3 - falciform edge of the fascia lata, 4 - upper horn of the falciform edge, 5 - subcutaneous cleft, closed by perforated fascia, 6 - spermatic cord, 7 - adductor longus muscle, 8 - lower horn of the falciform edge , 9 – sartorius muscle
Within the femoral triangle, the own fascia of the thigh (fascia lata) forms an opening closed by a loose connective tissue plate - subcutaneous cleft, hiatus saphenus. This cleft is limited on the lateral side by a thickened edge of the fascia lata - a crescent-shaped edge that has an arched shape. Above, under the inguinal ligament, the falcate edge forms the superior horn, and below, above the sartorius muscle, the inferior horn.
If we examine the area of the femoral triangle after removing the fascia lata and dissecting the muscles, we find the following (Fig. 20):
^
Rice. 20. The area of the femoral triangle (highlighted by a dotted line) after muscle preparation.
1 – inguinal ligament, 2 – long adductor muscle, 3 – sartorius muscle, 4 – pectineus muscle, 5 – iliopectineal groove, 6 – iliopsoas muscle
^ Bottom of the femoral triangle form two muscles:
iliopsoas muscle
pectineus muscle, covered with a deep layer of the lata fascia of the thigh - the iliopectineal fascia.
In the upper part of the triangle, under the inguinal ligament, two spaces are formed - the muscular and vascular lacunae (Fig. 21).
^
Rice. 21. Vascular (A) and muscular (B) lacunae
1 - inguinal ligament, 2 - iliopectineal arch, 3 - femoral artery, 4 - femoral vein, 5 - deep femoral ring, 6 - lacunar ligament, 7 - pectineal fascia, 8 - pectineus muscle, 9 - iliopsoas muscle, 10 – femoral nerve
Vascular lacuna(A) limited:
above – inguinal ligament;
from below – by the iliopectineal fascia;
Laterally – by the iliopectineal arch;
medially - lacunar ligament.
laterally and inferiorly – by the ilium;
above – inguinal ligament;
medially – iliopectineal arch
The iliopsoas muscle and femoral nerve enter the thigh through the muscular lacuna, and the femoral vessels (artery and vein) exit through the vascular lacuna.
In the medial corner of the vascular lacuna, one of the weak points of the abdominal wall is formed - deep femoral ring. This ring (Fig. 21, 22) is limited:
above – inguinal ligament;
laterally – femoral vein;
medially – lacunar ligament;
from below - the pectineal ligament (thickening of the iliopectineal fascia).
Fine this ring is closed by the transversalis fascia and lymph nodes, but under certain conditions they can pass through it femoral hernia. In this case, the hernial sac, emerging onto the thigh, forms a new structure that does not exist normally - femoral canal(Fig. 23). Its walls become:
From the inside – the iliopectineal fascia;
Laterally – femoral vein;
Anteriorly – the inguinal ligament and the superior horn of the falciform edge of the fascia lata.
The subcutaneous cleft becomes the external opening of the femoral canal. Therefore, when examining a patient with acute abdominal pain, it is imperative to examine the area of the femoral triangle so as not to miss a strangulated femoral hernia.
^
Rice. 22. Deep femoral ring (highlighted by dotted line). Inside view
1 – inguinal ligament, 2 – lacunar ligament, 3 – pubic bone, 4 – femoral vein, 5 – vas deferens, 6 – deep femoral ring 
Rice. 23. Femoral canal (highlighted by dotted lines)
1 – inguinal ligament (cut), 2 – upper horn of the falciform edge of the fascia lata (cut), 3 – iliopectineal fascia, 4 – lower horn of the falciform edge of the fascia lata, 5 – femoral vein, 6 – spermatic cord, 7 – adductor cleft (external opening of the femoral canal; conventionally indicated by a white dotted line)
^ 2. DRIVE CHANNEL
P 
adductor canal, canalis adductorius, is a continuation of the femoral groove (Fig. 24) and connects the anterior region of the thigh with the popliteal fossa.
femoral groove, which is a continuation of the iliopectineal groove of the femoral triangle (see Fig. 21), limited to:
Medially – long and large adductor muscles;
Laterally – vastus medialis muscle
Rice. 24. Femoral groove and adductor canal. The course of the adductor canal is highlighted with a white dotted line.
1 – femoral groove (highlighted by a dotted line), 2 – adductor longus, 3 – adductor brevis, 3 – adductor magnus, 4 – superior opening of the adductor canal, 5 – vastus medialis, 6 – lamina vastoadductoria, 7 – anterior opening of the adductor canal, 8 – lower opening of the canal (adductor cleft), 9 – semimembranosus muscle
^ The adductor canal has three walls and three openings: inlet (upper), outlet (lower) and anterior. The walls of the adductor canal are:
Medially – adductor magnus;
Laterally – vastus medialis muscle (part of the quadriceps muscle);
In front is a fibrous plate (lamina vastoadductoria), which is thrown between these two muscles.
^ Top hole the canal continues the femoral groove;
Front hole located in the fibrous plate;
Bottom hole(see Fig. 25), opening into the popliteal fossa, is located in adductor cleft– the gap between the fascicles of the adductor magnus muscle, attached to the linea aspera, and the fascicle attached to the medial epicondyle of the femur
^
Rice. 25. Afferent cleft – the lower opening of the adductor canal (highlighted by a dotted line)
1 - adductor magnus muscle, 2 - semimembranosus muscle, 3 - semitendinosus muscle, 4 - tendon of the adductor magnus muscle, attached to the medial epicondyle of the femur, 5 - medial epicondyle of the femur, 6 - biceps femoris muscle (long head), 7 - short head of the biceps femoris muscles, 8 – popliteal vessels, 9 - calf muscle
^ 3. Obturator canal
Obturator canal, canalis obturatorius, forms in the wall of the pelvis, at the upper edge obturator foramen.
Channel inlet located on the inner wall of the pelvis (Fig. 26);
The canal walls are formed:
Obturator groove of the pubis;
The superior edge of the obturator internus muscle;
The superior edge of the obturator externus muscle.
^
Rice. 26. Inlet of the obturator canal (highlighted by a dotted line).
1 - pubic bone, 2 - internal opening of the canal in the obturator fascia, 3 - symphysis pubis, 4 - obturator fascia covering the obturator internus muscle, 5 - piriformis muscle, 6 - levator ani muscle
The obturator artery and nerve pass through the obturator canal. In rare cases, it can become the site of obturator hernia formation.
^
Rice. 27. Outlet of the obturator canal (highlighted by a white line and an index arrow)
1 - iliopsoas muscle, 2 - pectineus muscle (opened), 3 - vastus medialis muscle, 4 - pubis, 5 - external obturator muscle, 6 - obturator nerve, 7 - adductor brevis muscle, 8 - adductor longus muscle
^ 4. SUPRYRAPHYIFORM AND INFRIPYRIFORM HOLES
E 
These holes are formed along the edges of the greater sciatic foramen when the piriformis muscle passes through it (Fig. 28)
^
Rice. 28. Suprapyriform (A) and infrapiriform (B) foramina (highlighted by dotted line)
1 – piriformis muscle, 2 – sacrotuberous ligament, 3 – sacrospinous ligament, 4 – obturator internus muscle, 5 – gluteus medius muscle, 6 – gluteus minimus muscle
Suprapiriform foramen (A) limited to:
Superior edge of the piriformis muscle
The superior edge of the greater sciatic foramen;
Inferior border of the piriformis muscle
The lower edge of the greater sciatic foramen
WITH 
strictly speaking, such an object is included in the nomenclature of topographic-anatomical formations lower limb Excluded. However, this cellular space should be highlighted for orientation in the topography of the largest nerve of the human body. It is located in the gluteal region and in the posterior thigh (Fig. 29).
In the gluteal region, the bed of the sciatic nerve is limited:
Posteriorly – the gluteus maximus muscle;
In front – pelvic muscles:
Piriformis muscle
Obturator internus muscle
Quadratus femoris muscle
Rice. 29. Bed of the sciatic nerve. The course of the nerve is indicated by a dotted line.
1 – gluteus maximus (opened), 2 – piriformis, 3 – obturator internus, 4 – quadratus femoris, 5 – ischial tuberosity, 6 – adductor magnus, 7 – vastus lateralis, 8 – short head of the biceps femoris , 9 – long head of the biceps femoris muscle (cut off), 10 – semimembranosus muscle, 11 – semitendinosus muscle (cut off), 12 – popliteal fossa
In the posterior region of the thigh, the bed of the sciatic nerve is limited:
In front – the adductor magnus muscle;
Medially – semimembranosus muscle;
Laterally – biceps femoris muscle.
^ 6. HEATH
Popliteal fossa, fossa poplitea, located posterior to knee joint, has a diamond shape and is limited to the following structures: 
The popliteal fossa communicates:
Above – with the adductor canal (through the adductor cleft) and with the bed of the sciatic nerve;
Below - with the ankle-popliteal canal.
Rice. 31. Projection of the course of the ankle-popliteal canal. The holes are highlighted with dotted lines.
1 – inlet of the canal, 2 – soleus muscle, 3 – gastrocnemius muscle (cut off), 4 – Achilles tendon, 5 – outlet of the canal
^
Rice. 32. The ankle-popliteal (A) and lower musculofibular (B) canals (highlighted with a dotted line).
1 – soleus muscle (cut off), 2 – superior opening of the ankle-popliteal canal, 3 – flexor digitorum longus, 4 – tibialis posterior muscle, 5 – flexor pollicis longus
^ The ankle-popliteal canal, canalis cruropopliteus (Fig. 31, 32), located in the posterior region of the lower leg. It has front and back walls, as well as three holes: top (input), front and bottom (output).
Top hole limited:
In front - the popliteal muscle;
Posteriorly – by the tendinous arch of the soleus muscle;
P 
middle hole(Fig. 33): located in the interosseous membrane at the level of the head of the fibula;
Bottom hole:
Located at the level of the beginning of the Achilles tendon;
It is represented by a gap between the tendon and the deep muscles.
The channel wall is formed:
WITH
Rice. 33. Anterior opening of the ankle-popliteal canal1 – anterior foramen, 2 – popliteus muscle, 3 – head of the fibula, 4 – soleus muscle (cut off), 5 – tibialis posterior muscle
anteriorly – tibialis posterior and flexor pollicis longus;
Posteriorly – the soleus muscle.
Inferior musculofibular canal branches off from the ankle-popliteal canal and is directed laterally downwards. The canal walls are formed:
In front – fibula;
Posteriorly – flexor hallucis longus.
The superior musculofibular canal is located on the lateral surface of the leg, spiraling around the fibula (Fig. 34):
^
Rice. 34. Projection of the course of the superior musculofibular canal (indicated by a dotted line).
A. side view:
1 – superior opening of the canal, 2 – head of the fibula, 3 – peroneus longus, 4 – lower opening of the canal, 5 – peroneus brevis, 6 – tibialis anterior, 7 – extensor digitorum longus;
^ B. Front view:
1 - superior opening of the canal, 2 - peroneus longus muscle, 3 - lower opening of the canal, 4 - peroneus brevis muscle, 5 - extensor digitorum longus, 6 - tibialis anterior muscle.
The canal begins with the superior opening along the line of the beginning of the long peroneus muscle from the fibula (Fig. 35).
WITH 
channel shadows are formed:
From the inside - the lateral surface of the fibula;
Externally – peroneus longus muscle.
The inferior opening of the canal is located between the peroneus longus muscle and the extensor digitorum longus muscle.
The superficial peroneal nerve passes through the canal.
Rice. 35. Superior opening of the superior musculofibular canal (highlighted in white dotted line)
1 – head of the fibula, 2 – peroneus longus, 3 – canal opening, 4 – soleus muscle (cut off)
Axillary fossa. fossa axillaris, is a depression between the lateral surface of the chest wall and the medial surface of the shoulder. At maximum abduction of the shoulder, the depression is well defined. If you remove the skin covering the fossa, the underlying fascia and loose fatty tissue, you will find a significant axillary cavity, cavum axillare, approaching in shape a four-sided pyramid, with the apex facing up and the base down. The base of the pyramid is also the lower aperture of the axillary cavity. In the area of the apex, the upper aperture of the axillary cavity is formed.
There are four walls that limit the axillary fossa: medial, lateral, anterior and posterior. The medial wall is formed by m. serratus anterior, lateral -m. coracobrachialis and caput breve m. bicipitis brachii, anterior - mm. pectorales, major et minor, posterior wall - m. subscapularis, m. teres major and latissimus dorsi. With the arm abducted, two more holes in the axillary fossa are clearly visible, formed by the passage of the long head of the triceps muscle between the teres major and minor muscles. The inner edge of the long head outside, the teres minor muscle above and the teres major muscle below limit the trilateral foramen (foramen trilaterum).
Lateral to the long head of the triceps muscle there is a quadrilateral foramen (foramen quadrilaterum), where the inner side is the outer surface of the long head of the triceps muscle, the upper one is m. teres minor, viewed from behind, or m. subscapularis, if viewed from the front, lower - m. teres major and outer side -
Muscular fossa, fossa axillaries, is a depression on the surface of the body between the lateral surface of the chest and the medial surface of the proximal shoulder. It is clearly visible with the arm abducted. In front it is limited by a fold of skin corresponding to the lower edge of the pectoralis major muscle. Posteriorly, the axillary fossa is limited by a fold of skin covering the lower edge of the latissimus dorsi muscle and the teres major muscle.
Axillary cavity is located deeper. It can be penetrated after cutting the skin in the area of the same fossa.
On the side of the base of the axillary cavity there is a wide opening - the lower aperture, aperture inferior, the boundaries of which correspond to the boundaries of the axillary fossa. Between the clavicle in front, the first rib medially and the upper edge of the scapula in the back there is the upper opening of the axillary cavity - the superior aperture, aperture superior, connecting the axillary cavity with the neck area.
On the back wall There are two axillary cavities holes- three-way and four-way.
Three way hole foramen trilaterum, located more medially, its walls are formed above by the lower edge of the subscapularis muscle, below by the teres major muscle, and on the lateral side by the long head of the triceps brachii muscle.
Four way hole foramen quadrilaterum, located outward. Its lateral wall is formed by the surgical neck of the shoulder, the medial wall is formed by the long head of the triceps brachii muscle, the upper wall is formed by the lower edge of the subscapularis muscle, and the lower wall is formed by the teres major muscle. Nerves and blood vessels pass through these openings.
Radial nerve canal.
Radial nerve canal or brachial canal,canalis nervi radialis, s. canalis humeromuscularis, located on the back surface of the shoulder, between the bone and the triceps muscle of the shoulder along the groove of the radial nerve. The entrance (upper) opening of the canal is located on the medial side at the level of the border between the upper and middle thirds of the body of the humerus. It is bounded by the bone, lateral and medial heads of the triceps brachii muscle.
The outlet (inferior) of the canal is located on the lateral side of the shoulder, between the brachialis and brachioradialis muscles, at the level of the border between the middle and lower thirds of the humerus. The radial nerve passes through this canal along with deep arteries and veins of the shoulder.
In the anterior region of the shoulder on the sides of the biceps brachii muscle there are two furrows: medial and lateral, sulcus bicipitalis medialis et sulcus bicipitalis lateralis. These grooves separate the anterior region of the shoulder (regio brachii anterior) from the posterior region (regio brachii posterior).