The structure of the arm (anatomy)

Content

  • 1We consider the structure of the hand in detail and detail
    • 1.1Functions and role in the body
    • 1.2Detailed structure
    • 1.3Bone structure
    • 1.4Joints
    • 1.5Muscles and ligaments
    • 1.6Blood vessels
    • 1.7Skin covers
  • 2Anatomy of the hands
    • 2.1Anatomy of human hands
    • 2.2Main arm muscles
    • 2.3Why shake hands
  • 3Human skeleton: structure. Skeleton of a human hand
    • 3.1Browse Partitions
    • 3.2Detailed structure of the shoulder girdle
    • 3.3Scapula
    • 3.4Collarbone
    • 3.5The structure of the shoulder
    • 3.6Structure of the elbow and forearm
    • 3.7Elbow bone
    • 3.8Radius
    • 3.9Wrist
    • 3.10Wrist
    • 3.11Pastern
    • 3.12Fingers
  • 4Brush: features of structure and function
    • 4.1Features of the structure of the brush
    • 4.2Wrist
    • 4.3Pastern (metacarpal)
    • 4.4Fingers (fingers of the hand)
    • 4.5Sesamoid bone
    • 4.6Bundles and muscles
    • 4.7Brush functions
  • 5Anatomy of the human hand
    • 5.1Joints and bones of the hand
    • 5.2Hand bunches
    • 5.3Muscles of the hand
    • 5.4Blood supply and innervation of the hand
  • 6Wrist
    • 6.1Structural features of the human hand
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    • 6.2Skin Properties
    • 6.3Bone apparatus
    • 6.4Muscular apparatus
    • 6.5Joints and ligaments
    • 6.6Innervation, or the nervous system
    • 6.7Blood supply of brushes
    • 6.8What is the difference between a human hand and a monkey?

We consider the structure of the hand in detail and detail

Anatomy of the arm is one of the most complex in our body. This is a whole system of bones, joints, veins, nerve endings, muscle tissue.

Together they act as a single mechanism, giving signals to the human brain.

The hand instantly reacts to the commands of the brain, performing many movements, helping a person perform a huge number of functions, protecting him from dangers.

Structural units of the brush:

  • Bones - in their hand there are already 27, divided into three departments - the wrist (these are the eight bones that connect with the help of ligaments), the pastern (five oblong bones, connects the fingers to the wrist) and fingers. Bones in the hand are small enough, but they are the frame of the brush, ensure its flexibility and stability.
  • Ligamentous apparatus - tendons, ligaments are an important part in any department, since they connect the skeleton with muscle tissue. They give the arm elasticity, flexibility, are part of the joints.
  • Vessels - feed tissues, supply oxygen.
  • Nerve endings - respond to external factors, signal to the brain about the need for action. Responsible for the sensitivity of the skin, contribute to muscle contraction, and also to their relaxation.
  • Skin is the protective cover of internal structures from the impact of the external world, regulates the temperature inside the limb.

Functions and role in the body

In the process of the evolution of the human body, when people got to their feet, their hands became a free substance, not burdened with the weight of a person's weight. As a result, the development of the hand has made it possible to master many new functions and actions.

In the modern world, since infancy, the basis of the child's brain development is the training of fine motor skills of the hands.

All this is not just because the length of the projection of the entire limb, and especially the thumb in the central gyrus of the brain, is equal to the projection of the rest of the human body.

The physical functions of the human hand are represented by three basic elements:

  1. straight open hand with straightened fingers - scoop;
  2. fold the fingers form a hook;
  3. A more complex element is capture. The scheme of its execution depends on the size, type of object, purpose, which forces the brush to develop a new technique for each case.

The main types of grippers are ball, shredded, planar, cylindrical, interdigital and plucked.

To implement each of them there is a close interaction of each limb element.

And if at least one structural unit is weakened, damaged, the brush can not fully cope with the performance of its functions.

It is worth noting also the psychological and emotional component of the hand's actions in people. The hands are very closely related to the emotional state of a person. When we are experiencing, nervous or tired, everything seems to fall from our hands. They stop listening to us.

Gestures are an important factor in our life.

Many people, when they say something, use their hands for a more emotional and accurate explanation of their point of view.

Hands also use deaf-mute people to communicate. They are their only way to communicate their thoughts and desires to others.

Detailed structure

As we have already described, the brush consists of several structural units, each of which has its own structural features, as well as functional tasks. Next, we will take a closer look at the structure of the brush.

Bone structure

The bones of the hand are represented by the wrist, the pastern and the fingers. The wrist is the basis of the skeletal system of the hand, represented by eight bones. The bones of the fingers of the hand are grouped together and form two rows.

One of which is represented by such bones as navicular, semilunar, trihedral and pea-shaped. The next row is trapezoid, hook-shaped and capitate.

All the bones of the brush consist of three parts - the base, the body and the head.

The next department is a pastern. It is represented by five bones, followed by the phalanges of the fingers. All but the big one consist of three phalanges.

A thumb of two, but stronger and more stable bones.

The thumb is a more autonomous structure, it is more mobile and as if opposed to all the rest.

Joints

Brush joints are classified by their location and are an important structural unit. Thanks to them, different bones connect with each other and allow the hand to perform various movements.

  • The wrist joint is the most complex in the limb, resembles the shape of an ellipse, is strengthened on all sides by ligaments and tendons. The main types of movements are flexion and extension of the hand. Can combine different movements.
  • The articulation is located between the proximal and distal rows of bones, forming a separate capsule with them.
  • Intervertebral joints connect the bones with each other, which gives the person the opportunity to grab, throw and many similar movements.
  • At the base of the big toe, a carpal joint of saddle shape is formed. Its peculiarity is that movements occur around two axes. This allows the large finger to more autonomously control grasping actions, to hold objects. This is the main feature of the human hand unlike other living beings.

Muscles and ligaments

The muscle tissue of the brush is a collection of many small muscles that are located around the bones on both sides.

They communicate with each other with the help of tendons and ligaments.

Together, the muscular apparatus allows the brush to perform the entire range of movements, facilitates the coordination and clarity of actions.

Every muscle is responsible for its movement. For example, one bends the brush, the other extends.

If any part of the muscular apparatus is damaged, the brush can not fully perform the slightest movements. It brings pain, discomfort or weakness in the hand.

Muscles need to be maintained in a tone that will allow them to be more hardy and strong.

Blood vessels

The entire brush is powered by a deep arterial arch in the palm of your hand, as well as a network of arteries on the back and palmar parts.

If the blood supply is damaged, or if it worsens, the hand receives less oxygen and begins to weakerly function.

In this case, the joints also do not get enough nutrition, and muscle tissue, and ligaments with tendons. The functionality of the brush may be completely impaired.

Skin covers

The skin protects the limbs from the effects of the external environment. It is multilayered, the upper layer is more coarse, gradually dies and peels off. Under the skin are sebaceous, sweat glands.

Important elements in the skin are elastin and collagen. They are responsible for the elasticity, youth and integrity of the skin. With age or a violation of metabolism in the body, these elements cease to be replenished in the right amount. As a result, the skin cracks, becomes wrinkled.

A source: https://prospinu.com/anatomija/kisti-ruk/stroenie-kisti-v-detalyax.html

Anatomy of the hands

Any athlete constantly dreams of beautiful hands, but few know about how the hands are made.Anatomy of the hands, the significance of its features, that's the whole secret of success.

The hands are given the biggest work.

The load in bodybuilding lies just on them: They athlete exercises with weights, constantly bends or unbends, exercising, planting or diverting.

It is important to have a clear understanding of these muscles, and clearly understand what areas are usually involved in the exercises.

The structure of the human hand

For some, it may seem that such information is uninteresting or generally boring, but these knowledge are extremely important. If you rely on theory, then pick up or even make a plan for training is not difficult. Moreover, it will bear fruit faster.

Anatomy of human hands

Anatomy of the human hands is the structure of the body part. Our muscles are composed of very heterogeneous muscles, which we need so much in everyday life.

One group is responsible for lifting loads, the other helps to drink, the third will help change.

All the work of the muscles is determined by the pressure exerted on the extensors or flexors of the shoulder, as well as the forearm.

All the muscles are divided into two groups: superficial, they can be clearly seen in the athlete with a spectacular relief body, and deep, they are hidden and buried deeply. The structure of the latter groups may be studied only from theory.

Main arm muscles

The main muscles of the arms include the biceps. It is such a muscle, it connects with the elbow with the help of tendons with ligaments.

It consists of a short head and a long one. They start on the shoulder blades, but in very different places.

They are united in the middle of the shoulders, but are joined below in a peculiar elevation of the forearm.

Muscles to be swung

Those who try to perform heavy loads all the time tend to have very developed biceps.

One of the main functions of these two-headed muscles is precisely the bending or raising of the hands.

Turning the palms to the sides, as well as lifting them upwards, allows the biceps to work as a supinator of the forearms.

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Triceps basically consist of some muscular heads, but in a well developed form, they can resemble something like a horseshoe:

  1. The lateral head goes down from the back of the arms, starting from the bones of the shoulder, ending with the elbow process. It represents the side of the shoulder divisions;
  2. The medial head, it begins also on the back of the shoulder, it is attached to the elbow;
  3. A long head. It begins at the bone of the shoulder, and it falls down to the elbow process, slightly covering the first two heads.

The triceps arm muscles are responsible for the divorce of the shoulders from our body, the bends of the elbows or the reduction to the trunk. All three types of triceps ligaments can be long or short. This is a feature of the genetics of people, it is impossible for us to influence this.

Muscles in the forearms still consist of the following groups: extensor and hind muscles. The largest are brachialysis muscles, cranoid and long radial flexors on the wrist.

In order to fully involve all target muscles in the work, it is necessary to clearly imagine what specific joints will be involved and what further work will be assigned to them.

The training of biceps in bodybuilding is affected by the three joints of the frontal parts of the arms: the shoulder joints, crossing the long head, ulnar, involved in the bend of the elbows of the joints and wrist, helping to change the pose of the forearm supination.

When training triceps also included in the work of all three of the above joints. When lifting on the hands, shoulder joints work, with full extension, only the elbows.

Why shake hands

Why shake hands if the main gravity is superimposed on the legs. Preliminary study what is the anatomy of the hands and the structure.

It is necessary to draw up a training plan in such a way that all parts of the body develop harmoniously. The upper extremities should be tried to train at least in a complex manner.

This is so necessary, because:

  • Beautiful ladies give their preference only to those men who have muscular arms. It reminds mentally the support and the reliable protection.
  • Beautiful muscles speak of a beautiful form, for which one is not ashamed.
  • Girls swing their hands is still due to the fact that the bumps under your hands forever gone.
  • Ladies who have developed forearms are much more confident can feel themselves in everyday life, easily carrying various heavy objects.
  • Strong hands will help protect yourself in any unpredictable situation.

The productivity of training will be higher if you understand correctly what specific exercises you can work out each muscle. As a revision of the biceps, exercises with lifting dumbbells or a barbell are quite suitable.

Try to emphasize the entire load on the long heads of the biceps. To do this, apply the spreads of your brush according to the known principle of "hammer".

For a complete pumping triceps, it is important to use the following types of exercises: unbend hands from behind the head, strictly narrow grip to perform bench press, repeat the French press, in a standing or standing posture, pushing away from the bench, pushing away from the bars or from the floor using the method of narrow grip, extension on the block hands.

For your forearms, the effective exercises will be the methods of hammer bending of hands together with dumbbells, and complex lifts to your biceps dumbbells, as well as the bends of the bar at the wrists.

In the upper limbs, our muscles are absolutely uncombed, and summing up, we can conclude that the best way is to implement a variety of exercises, as well as experiments with them.

A source: https://omolodet.ru/anatomiya-ruk/

Human skeleton: structure. Skeleton of a human hand

The human skeleton can be divided into 4 sections. The upper is the belt of the upper limb. This includes a scapula and collarbone. Next comes the actual anatomical shoulder, that is,

section of humerus. The next section is the forearm, consisting of the elbow and radius. The last one is the bones of the brush.

The skeleton of the left hand is a mirror image of the right skeleton.

Browse Partitions

Consider the skeleton of the hand for each section. The scapula and clavicle connect with each other, and the brachium connects them to the humerus. But not only the humerus joins them. They serve as a place of attachment for the muscles that are responsible for the movement of the hand.

Next comes the humerus directly. To her through the elbow joint fastened radial and ulnar. The latter are mobile relative to each other. With the position of the hand, when the palm looks inward, these bones are parallel, but it is necessary to turn the palm forward, as they shift and cross.

The skeleton of the hand is the most complex. The structure includes 27 bones. These elements are further divided into several groups: the wrist, the pastern and the phalanges of the fingers, which are connected through the interphalangeal joints.

It is the complexity of this device and allows the hands to be so versatile and skillful. With its help you can do rough work with mechanical operations, but it also allows you to perform fine precise movements.

Detailed structure of the shoulder girdle

The skeleton of the arm in the shoulder girdle is represented by a scapula and clavicle. It is the area of ​​their placement and connection with the humerus and is called the shoulder in everyday life.

However, the humerus is an anatomical shoulder, and these elements constitute the belt of the upper limb.

But, considering the skeleton of the human hand, the structure should be studied together with the shoulder belt, which significantly affects the functionality.

Scapula

Shoulder - a flat bone from the back. Has a triangular shape with the upper, lateral and medial margins and the lower, upper and lateral angles.

It is the thickened lateral corner that is provided with the articular cavity where the articulation of the scapula with the head located in the next section of the humerus occurs.

A little above the cavity is the neck of the scapula, which looks like a narrowed place. The articular cavity is also surrounded by tubercles - subarticular and suprasensitive.

The scapula itself has a somewhat concave surface - a subscapular fossa - in the region of the ribs from the side of the thorax. But on the back surface there is a bone that runs along the shoulder from the inner edge to the outer corner.

On the sides of the awning there is a submental and subacute fossa, where the muscles with the same names are attached. Outwardly, this awn passes into the shoulder process located above the shoulder joint, called the acromion.

Another scapula is provided with a beak-like process, facing forward and serving to fasten ligaments and muscles.

Collarbone

The clavicle is a tubular bone, curved S-shaped. Has a horizontal position, goes in the upper front of the chest near the neck.

The medial sternal end is attached to the sternum, and the acromial lateral connects to the scapula.

Also, the fastening is done by the muscles and ligaments, which causes the presence of a roughness on the lower surface, namely the line and the tubercle.

The structure of the shoulder

Behind the shoulder belt goes directly to the skeleton of the human hand. The shoulder is formed by the humerus bone. It is a tubular bone, rounded in cross section from the upper side and triangular closer to the bottom.

The upper end is crowned with a hemispherical head that is facing towards the scapula. The head has an articular surface. A little lower is the anatomical neck of the bone and two tubercles for fixing the muscles.

A large hill is facing outward, and a small one comes to the front. From each the ridge goes down, but between it and the tubercles there is a furrow for the passage of the tendon.

The narrowest part of the bone was called the surgical neck.

The body of the bone is called the diaphysis. The deltoid tuberosity on its outer surface is designed to hold the deltoid muscle. And the posterior surface is decorated with a furrow of the radial nerve, which runs slightly along a spiral.

The distal epiphysis is the lower end of this bone. Here the condyle and articular surface is formed, through which the bone connects to the next section. The block of the humerus is the medial part of the joint that joins the ulna.

The lateral part of the spherical form - the head of the condyle - connects with the radius bone. Above the block, two pits are provided, where the processes of the ulnar bone go with the movements of the arm, they are called the pits of the coronoid and the ulnar process.

Also, near the distal end there are epicondyle (lateral and medial), where ligaments and muscles are attached.

Structure of the elbow and forearm

The forearm is the site of the limb from the elbow to the wrist. In everyday life this part was often called an elbow, including used as a measure.

In the elbow joint includes the elbow and radius of the forearm and the humerus itself. The skeleton of the arm of this department is represented by the ulna and radius bone.

They are interconnected with each other in a flexible manner: the ray one has the opportunity to rotate around the elbow during movement of the hand. Due to this, the brush can be rotated up to 180º.

Elbow bone

The elbow is triangular in shape. The upper end is thickened, provided with a block-shaped notch from the front, to be joined to the humerus.

The lateral edge ends with a radial notch, which is needed to connect to the head of the second bone of the forearm - the radial. The coronal anterior process and the ulnar posterior go along both sides of the block-shaped notch.

Under the anterior process there is tuberosity for fastening the brachial muscle. The head is located on the distal lower end of this bone. The articular surface on its radial side serves to articulate with the radial bone.

The head of the ulna is also provided with a subulate appendage on the posterior margin.

Radius

The radius of the radial bone was thickened at the lower end, and not on the upper end, as in the ulnar. On the upper side is the head of the radius, which allows you to connect with the humerus.

The upper surface of the head has a pit, which is needed for articulation with the head of the condyle located on the humerus bone. The articular circumference along the edge of the head allows to connect with the ulna. The head narrows downward, passing into the neck of the radius.

On the inner side just below the cervix, tuberosity makes it possible to attach the biceps arm muscle to the tendons.

The lower end of this bone is equipped with a carpal articular surface that connects this section with a brush.

There is also a styloid process, turned to the outside, and on the inner side there is an elbow cut, intended for articulation with the corresponding head of the ulna.

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Also, the skeleton of the hand in this place contains a limited intercostal space enclosed between the sharp edges of the bones of the forearm.

Wrist

The skeleton of the human hand is divided into the wrist, the pastern and the fingers themselves. Each department is made up of a number of bones and moving joints. This structure allows you to perform a variety of actions by the hands, deftly and quickly work even with small details.

Wrist

The skeleton of the hand starts with the wrist. In it are located just eight bones, small in size and irregular in shape. These are spongy bones. They are arranged in two rows.

Here one distinguishes a pea-like, trihedral, semilunar and scaphoid bone of one row, and the second is hook-shaped, capitate, trapezoidal and polygonal.

The first proximal row serves as the articular surface necessary for articulation with the radius. The second row is distal, connected to the first joint of irregular shape.

Located in different planes, the bones of the wrist form a so-called wrist groove from the palm, and on the back side there is a bulge. From the furrow of the wrist go tendons, which are responsible for the work of flexor muscles.

Pastern

The pastern is formed by five metacarpal bones. These are tubular bones consisting of a body, a base and a head.

The skeleton of the human hand is distinguished by a large thumb opposition to the rest and its best development, which greatly increases the possibilities of the limb.

To the big finger there is a shorter, but more massive bone. The bases of these bones are connected with the bones of the wrist.

In this case, the joint surfaces for the outer fingers have a saddle shape, and the rest are articular surfaces of a flat type. The head of the hemispherical articular surface connects metacarpal bones with phalanges.

Fingers

The bones of the fingers consist of two or three phalanges: the first consists of two, and the rest consists of three. The length of the phalanges decreases when removed from the pastern.

Each phalanx consists of three parts: a body with a base and a head at the ends.

Phalanges end with articular surfaces at both ends, which is due to the need for an articular joint with further bones.

Between the proximal phalanx and the metacarpal bone of the large (first) finger there are still sesamoid bones hidden by the tendons.

It is worth noting that sometimes there is an individual structure of the hand: the skeleton of the brush can be supplemented with other elements.

Sesamoid bones can also be in a similar place near the second and fifth fingers. The muscles are attached to these elements (as well as to bone processes).

A source: http://.ru/article/178538/skelet-ruki-cheloveka-stroenie-skelet-kisti-ruki-cheloveka

Brush: features of structure and function

If a person had no hands, it would not be easy for him. After all, the hands are multifunctional and allow a person to perform many different actions.

But do not forget that the most fragile part of a person's hand is a brush. It is the joint head that suffers first from bruises, sprains or fractures.

Therefore, the brush should be protected, because without them a person has not learned how to manage.

Features of the structure of the brush

Brushes of the left and right limbs of a person have a mirror structure and consist of:

  1. wrists;
  2. pastern;
  3. fingers.

Each department is built of bone, joint and tendon tissue, which allows you to perform actions and work even with the smallest objects and details.

Wrist

The structure of the human wrist is peculiar. It consists of eight different bones, distributed in two rows - adaxial and distal.

In the proximal row are the scaphoid, semilunar, triangular and pea-like bones of the hand. In the distal - polygonal, trapezoidal, capitate and hooked.

The peculiarity of them is that they are all spongy. In addition, they have an irregular shape.

The proximal layer of bones acts as a joint, which is necessary for adhesion to the forearm. In this case, the distal bones are articulated with the adaxial ones with the help of an incorrect joint.

Bones of the human wrist are placed in different planes, due to this, a groove (trough) is formed on the palmar plane and a bump in the interior.

The tendons in the gutter are responsible for flexion-extension. The anatomical structure of the furrow has its own characteristics. Its rear edge ends in a pea-shaped bone and a hook of a hook-shaped bone.

The outer surface is multifaceted and scaphoid bones.

Pastern (metacarpal)

The human pastern is formed by the metacarpal bones. The peculiarity of them is that they are tubular bones with a body, a base and a head. The construction of the human skeleton is distinguished by a high degree of resistance to the bones, thereby increasing the functionality of the limb.

The anatomy of the pastern is such that the metacarpus of the first finger is considered the most massive and short in comparison with the rest. In this case, the longest is the second pivot of the pastern. If you look at the palm from the right to the left, then each next bone is shorter than the previous one.

All metacarpals are connected to the wrist. The first and fifth bones of the pastern have a saddle-shaped form of the joint. And the second, third and fourth are represented by a flat surface of the joint. The ends of the palm are characterized by a hemispherical shape of the joint and are connected to the adaxial phalanx.

Fingers (fingers of the hand)

The anatomical structure of each finger is the same. It consists of several phalanges - proximal, distal and medium. It should be noted that the main exception is a large finger, which does not have a central phalanx.

It should be remembered that the longest - adaxial phalanges, and the small - distal. Any phalanx consists of such parts: adaxial and distal end and body.

At the edge of each phalangeal bony there is a joint plane, designed to connect with the rest of the bones.

Sesamoid bone

The anatomical structure of the limb also includes the presence of sesamoid bones that are distributed in the mass of the tendon between the first finger and the adaxial phalanx. You can also see variable sesamiform bones located between the adaxial phalanx and the metacarpus of the index finger and little finger.

The structure of the limb is such that the cesarea-shaped bones are on the palm of the hand. But do not forget that sometimes they are viewed on the back of the brush.

Bundles and muscles

Muscle tissue is located on the palm, forming the main muscle groups:

  • middle (it is located in the center of the plane of the palm);
  • the thumb;
  • little finger.

The middle group of muscles consists of vermicular muscle tissue, which starts from the tendon of the inferior finger flexor and is attached to the base of the adaxial phalanges. This construction of the muscle tissue allows you to bend-unbend fingers.

It should be noted that the interosseous muscles of the palm, when the fist is compressed, reduce the fingers to the third finger, and the rear, on the contrary, separate in different directions.

The muscles of the thumb create a so-called "tubercle" and originate on the adjacent wrists and metacarpal bones.

Isolate a shortened muscle, which is responsible for the movement of the first finger, a small flexor of the first finger, muscle tissue, which deals with the opposition of the fingers and muscles, leading the first finger.

Muscles of the little finger have settled on a palm from within. This includes muscles that divert the small finger, the extensor flexor and the muscles that oppose the small finger.

Brush functions

Brush is a universal and unique part of the body. Upper limbs are the main organ of labor.

Speaking about a person, it should be noted that the brush can not be regarded as a separate element of the body. The general physical and psychological state of people affects the functioning of the limbs.

The main functions of the upper limbs are touch and gesture.The tips distribute the main nerve endings, allowing people with limited vision to feel the shape, size, temperature and read.

Proceeding from all the above, it can be argued that the hand is an intermediary between man and the world around him.

A source: http://drpozvonkov.ru/sustavy/anatomy/stroenie-kisti-ruki-cheloveka.html

Anatomy of the human hand

The man's brush, or the distal part of the upper limb, has a special meaning.

With the help of hands and fine motor skills, movements of all fingers, people come to know the world and interact with it. Brush and fingers are the main tools in any job.

Reducing their functionality in many ways leads to a decrease in working capacity, to the limitation of human capabilities.

Joints and bones of the hand

The anatomy of the human hand is distinguished by the presence of small bones that are articulated by joints of various types.

There are three components of the wrist: wrist, metacarpal, phalanges of fingers.

The wrist in simple usage is called the wrist joint, but from the anatomical point of view it is the proximal part of the hand. It consists of 8 bones arranged in two rows.

The first proximal row consists of three bones connected by fixed joints.

To it, from the lateral outer side, there is a pea-shaped bone, which is inherited from a distant ancestor and serves to strengthen the muscular strength (one of the sesamoid bones).

The bony surface of the first row, facing the bones of the forearm, forms a single joint surface for connection with the radius.

Bones of the hand

The second row of bones is represented by four bones distally connected to the pastern. The wrist portion in form resembles a small boat, where the palm surface is its concave part.

The space between the bones is filled with articular cartilage, connective tissue, nerves and blood vessels. Movement in the wrist itself and the movement of its bones relative to each other are almost impossible.

But thanks to the presence of the joint between the wrist part and the radius bone, a person can rotate the brush, bring it and withdraw.

Hand joints

The metacarpal part consists of five tubular bones.

Their proximal part is connected to the wrist by immobile joints, and the distal part is connected to the proximal phalanges of the fingers by movable joints.

Pseudo-phalangeal joints are globular joints. They make it possible to perform bending and extension and rotational movements.

The joint of the big toe has a saddle shape and provides only extension and flexion. Each finger is represented by three phalanges joined by means of movable block joints.

They perform flexion and extension of the fingers. All joints of the hand have strong articular capsules. Sometimes she capsule can combine 2-3 joints.

To strengthen the osteoarticular carcass there is a ligamentous apparatus.

Hand bunches

The joints of the human hand are held and protected by a whole set of ligaments. They have increased elasticity and at the same time strength due to very dense fibers from the connective tissue.

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Their function is to provide movement in joints no more than a physiological norm, to protect them from injuries.

In cases of application of increased physical effort (falling, lifting of weights), the ligaments of the hand can still be stretched, the cases of rupture are very rare.

The ligamentous apparatus of the hand is represented by numerous ligaments: interarticulate, dorsal, palmar, collateral. The palm part of the hand is blocked by the flexor holder.

It forms a single channel in which the tendons of the flexor muscle of the fingers pass.

The palmar ligaments go in different directions, creating a thick fibrous layer, the rear ligaments are smaller.

Metacarpophalangeal and interphalangeal joints are strengthened by lateral collateral ligaments, and also have additional ones on the palmar surface.

The flexor-retainer ligament on the palm and the extensor retainer on the back are involved in creating fibrous vaginas for these muscles.

Thanks to them and the synovial spaces, the tendons are protected from external influences.

Muscles of the hand

Studying the anatomy of the hand of a person, one can not ignore the perfection of the device of her muscular apparatus.

All the smallest and most precise movements of the fingers would be impossible without the coordinated work of all the carpal muscles. All of them are located only on the palm of the hand, the tendon of the extensor extends on the back side.

By the location of the muscle of the hand can be divided into three groups: the muscles of the thumb, the middle group and the small finger.

Muscles and tendons of the hand

The middle group is represented by interosseous muscles connecting the bones of the metacarpal part, and vermicular, which are attached to the phalanx.

Fold and bend the fingers of the interosseous muscles, and the wormlike ones bend in the metacarpophalangeal joints.

The muscle group of the thumb is the so-called tenar, the elevation of the thumb. They bend it and unbend it, withdraw it and lead it.

Hypotenar, or the elevation of the small finger (little finger) is on the other side of the palm.

The muscular group of the small finger contrasts it, withdraws and leads it, bends it and unbends it.

The movements of the hand in the wrist joint are provided by the muscles on the forearm, by attaching their tendons to the bones of the hand.

Muscles and tendons

Blood supply and innervation of the hand

Bones and joints, muscles and ligament brushes are literally permeated with blood vessels. The blood supply is developed very well, due to which a high differentiation of movements and rapid regeneration of tissues is ensured.

From the forearm to the hand, two arteries, the ulna and the ray, approach, and, passing through special channels through the wrist joint, are between the muscles and the bones of the hand.

Here between them an anastomosis (connection) is formed in the form of a deep and superficial arc.

From the arches to the fingers, smaller arteries depart, each finger is supplied with four vessels. These arteries also join together, forming a network. Such a branched type of blood vessels helps with injuries, when the blood supply to the fingers suffers insignificantly when a branch is injured.

Artery of the hand

The ulnar, radial and median nerves, passing through all the elements of the brush, end on the fingertips with a huge number of receptors. Their function is to provide tactile, temperature and pain sensitivity.

Nerves of the hand

Harmonious and harmonious work of the hand is possible only with the preserved functionality of all its components. A healthy brush is necessary for a person's full life, preservation of his work capacity.

A source: http://artroz-plus.ru/anatomiya-kisti-ruki-cheloveka

Wrist

One of the most functional elements of the human body is the brush. It is this device that extols the Intelligent Person over many mammals.

Imagine a full life without healthy hands and hands is quite difficult. Even the simplest daily movements of hands (teeth cleaning, button fastening, combing) will be impossible with injuries of the upper limb.

The structure of the hand has a number of features, try to understand the main.

Structural features of the human hand

The human brush has a specific and complex structure. Anatomy of the hand is a complex complex mechanism, consisting of various elements:

  1. Bone skeleton (carpal skeleton) provides firmness and strength of the entire limb.
  2. Tendons and ligaments connect the bone base and muscles, provide elasticity and flexibility of the limb, and also participate in the formation of joints.
  3. Vessels provide nutrition to the tissues of the hand and their supply with oxygen.
  4. Nerve fibers are responsible for the sensitivity of the skin of the limb, contraction and relaxation of the muscles, provide a reflex response to an external stimulus.
  5. Skin covers perform a protective function, delimiting the structure of the brush from environmental factors, regulate the internal temperature.

Each constituent part of the human hand performs its functions, but together they provide the execution of various manipulations with a brush, from the most simple to complex. The figure shows the main elements of the upper limb.

Skin Properties

The skin covers the entire body, somewhere it is more tender, somewhere coarser. What determines the nature of the skin? Everyone knows that the palm has a thicker skin than the back surface.

This is due to the fact that it is the palm surface of the brush that is most often subjected to friction, chemical and mechanical effects.

Thus, the protection of muscles, vessels and nerve fibers by the skin from the effects of the environment is realized.

The back surface has more sebaceous and sweat glands than the palmar surface.

Elasticity of the skin of hands and its elasticity depend on the amount of collagen and elastin in it, which are specific proteins. These substances are destroyed by the action of ultraviolet radiation.

When the content of collagen and elastic fibers is reduced in the thickness of the skin of the hands, dryness, wrinkling, and cracking are observed.

These signs are more common in women of advanced age, but there are exceptions. One of the earliest symptoms of the excessive influence of ultraviolet radiation on the skin is the appearance of pigmented spots.

Bone apparatus

How many bones are in the person's hand? This question was asked to ourselves at least once by each of us. The hand is made of 27 small bones. So, the human brush consists of several sections:

  • Wrist - is a structure consisting of 8 grouped bones, connected together by a ligamentous apparatus. The wrist includes such bones as: navicular, trapezoid, pea-shaped, triangular, trapezoid, hook-shaped, capitate, semilunar.
  • Pastern - represents a series consisting of five oblong bones. This brush section is located between the wrist and the fingers of the hand.
  • Fingers of the hand - four fingers of 3 phalanges and a large of two-phalanx.

The bones of the brush are rather small, however, it is their small size that increases the flexibility and stability of the arm frame when physically affecting the skeleton.

Bones of the hand are most often subjected to significant stress. After all, each of us at least once in my life noticed that when the reflex is falling, the upper limbs are pushed forward.

Muscular apparatus

Undoubtedly, brush movements would be impossible without the involvement of muscles. Skeletal muscles of the hand and fingers provide clarity and coordination of movements in them.

The muscular apparatus of the hand consists of a set of separate muscles arranged in layers on both sides. Some of them are responsible for bending the palm, others for its extension. To the bones, the muscles of the hand are attached by means of tendons and ligaments.

Damage to any of the above components of the hand makes it impossible to perform its basic functions. The muscles of the hand pass into the tendons, which are attached to the bone base.

Thus, due to the well-coordinated work of the nervous, vascular and ligamentous-muscular systems, the entire skeleton moves.

Joints and ligaments

The most complex and important wrist joint is the wrist. The wrist joint is formed by the elbow, wrist and elbow wrist and wrist. The bones of the elbow form a complex ellipsoidal joint with a wrist.

Its value is quite large, as it is one of the few joint articulations providing combined hand movements (rotation, flexion and extension). The wrist joint is considered the key joint of the upper limb.

However, one should not underestimate the role of all other joints of the hand, since only together they form a complete skeleton of the hand.

The well-coordinated work of the wrist and other joints ensures its normal and full functioning.

Thanks to the normal mobility in the joints, the muscles of the hand can fully contract and relax, causing the skeleton to move. The following figure gives an idea of ​​how the wrist and other joints of the upper limb are located.

Innervation, or the nervous system

Many are mistaken, believing that the back of the hand is most equipped with nerve endings. In fact, most of them are at the fingertips. It is the abundance of nerve endings at the fingertips that provides tactile and sensory sensitivity.

In people with visual impairments (especially congenital), the ability to perceive the world through the touch of the fingertips is especially developed. Such sensitive areas protect the nails. Nail plates are formed from keratin.

If the amount of keratin in the nails is reduced, then they become brittle and thin.

Blood supply of brushes

Nutrition of all structures of the human hand is provided by the radial and ulnar arteries, forming a deep and superficial arcs of blood supply. Abundance of blood vessels and a complex network of anastomoses provide the most effective work of the limb.

What is the difference between a human hand and a monkey?

We all remember from the school program one of the most famous theories of the origin of man from primates. Indeed, the human body (including the skeleton) has certain similarities to the body of primates. The same applies to the structure of the brush.

However, if you comply with this hypothesis, the human brush has evolved significantly. The evolutionary "engine" of this development is labor.

Thus, the human upper limb has a number of structural features:

  1. saddle shape of 1st carpometacarpal joint;
  2. the trough for the tendons of the hand, nerve fibers and vessels in the wrist area is deepened;
  3. the bones of the 1st finger became wider in comparison with others;
  4. the length of the phalanx from the 2nd to the 5th fingers is shorter than that of the monkey;
  5. The palm bones of the hand, which are connected with the 1st finger, are displaced towards the palm.

The structure of the hand of the human hand has a number of features that ensure the performance of precise and coordinated movements.

A source: http://sustavam.ru/anatomiya/kist-ruki/