The anatomy of the brachial plexus is considered in a specialized course of in-depth study of biology in the school curriculum, as well as at the university in specialties related to medicine. However, the topic is quite interesting, so it is useful even for an amateur to get to know it. Features of the anatomy of the brachial plexus allow us to understand the causes of possible problems, pains. You can understand the abundance of pathologies and the causes of their occurrence. Curious connection of the spinal nerves. The anatomy of the brachial plexus gives a fairly accurate picture of them, allowing us to realize the complexity of the human body. However, it should be noted that at the moment, scientists can not say with certainty that the nervous system of the spinal cord has really been studied. It is believed that we have yet to uncover natural puzzles.
general information
Considering the anatomy of key weaving, one can notice that the organ is formed by nerve branches. One begins at the first thoracic, another four go from the cervical front from the bottom. The plexus is located behind the clavicle, directed towards the axillary fossa.
The anatomy of the brachial plexus is not only a feature of the position and structure of organs, but also their correct name. In Latin, this tissue complex is called plexus brachialis. It is customary to divide into two elements: above the collarbone and below it.
Over the collarbone
The anatomy of the human brachial plexus in this area is quite interesting. Tissues are formed by rather short nerve fibers through which the muscles of the arm are supplied. Nerves are located near the scapula, on the body. In short, the anatomy of the brachial plexus provides the following muscle tissue:
- in the shape of a rhombus;
- responsible for raising the scapula;
- notched in front;
- chest (large, small);
- the widest;
- located under the scapula;
- sub-, supraspinatus;
- big round.
Subclavian
The anatomy of the normal brachial plexus in this part involves the formation of three trunks in the axillary fossa. They are called respectively: lower, central, located on top. These tissues give rise to the long nerves of the arm. The cutaneous muscle nerve starts from the trunk from above. An interesting feature of the anatomy of the cervical, brachial plexus is that it is from this area that the root of the median nerve originates.
The trunk at the bottom also gives rise to the spine of the same center in the middle. Additionally, it is from here that the cutaneous nerves begin, providing sensitivity to the forearm, shoulder area. The trunk below is the starting point of the nerve of the elbow. But from the central part the start of the nerves starts: axillary, radialis (radial). As can be understood from such general information on anatomy, the brachial plexus pattern is quite complex. Nature has created a really very subtle and surprisingly sensitive mechanism, thanks to which a person has mobility, sensitivity.
Muscle cutaneous nerve tissue
If you carefully consider the anatomy of the brachial plexus in the photo, this nerve tissue can be found among the elements that ensure the operability of the parts responsible for the bending processes. Fibers pass here through the brachial clavicular muscle tissue. This provides muscle nutrition:
- two-headed;
- shoulder areas;
- clavicular in the shoulder area.
When the nervous tissue reaches the forearm, through it the sensitivity, functionality of the skin is provided. Thus, the lateral part of the forearm is nourished. The correct name of the nervous tissue in Latin is musculo-cutaneus.
Median nerve
In anatomy, medicine, this tissue is known as medianus. Start is taken from the medial, lateral roots. Reaching the shoulder, nerve fibers become a companion to the brachial artery. An interesting feature of this stage is the complete absence of branches. Reaching the forearm, the median nerve occupies a position between the deep digital flexors and those located on the surface.
The carpal tunnel allows the median nerve to reach the palm. Here, the organ is divided into three elements that provide the functionality, sensitivity of human fingers. Through the median nerve, vitality, performance of the pronators is realized. With the incorrect functioning of this element, the forearm flexors can not work normally. The median nerve provides anatomical functions of the muscle tissue of the hand, fingers, palm.
Ulnar nerve
Correct Latin name for ulnaris fabrics. A distinctive feature is the absence of branches within the human shoulder. As soon as the nerve reaches the forearm, it turns into an element of first importance for the carpal elbow flexor, as it provides its functionality, realizing a connection with the human nervous system. On the forearm, the ulnar nerve extends in the interval between the epicondyle of the shoulder bone in the center and the process of the elbow.
Branching of the ulnar nerve is observed when approaching the pisiform bone tissue. End branches form here. Through them, the functionality of the carpal muscles, the sensitivity of the skin is provided.
Radial nerve
This fabric, in comparison with others that form the human brachial plexus, is the thickest. The correct Latin name for the organ is radialis. Studies have shown that nerve tissue with anatomically correct growth is located behind the artery of the shoulder. Gradually, the organ develops in the direction of the triceps brachii, penetrating into the thickness and providing its connection with the human nervous system.
It is through the radial nerve that the sensitivity of the skin near the brachial triceps muscle, on the forearm from the back, is provided. Next, the radial nerve is directed around the spiral bone tissue of the shoulder towards the ulnar fossa. Here, in the depths of this part, there is a division into two elements: a branch that goes to the surface, and a deep one. The first is a companion to the radial artery, providing functionality to the skin of the hand. The second goes to the forearm from the back. Through a deep branch, the entire muscle tissue of this group is operational.
Axillary nerve
The anatomical task of this tissue is to provide communication with the nervous system of the small round muscle tissue and formed in the shape of a delta. Through the nerve, the shoulder joint's working capacity is realized, and the sensitivity of the skin of this region is ensured.
When tissues were affected: some pathologies
If, for any reason, the plexus is complex, it becomes the cause of the development of peripheral muscle paralysis. Hands suffer from hypesthesia. If the lesion is high, in addition, the muscle tissue of the shoulder blades is included in the pathological process. Often, the symptoms of Horner are fixed in patients.
If the roots C5, C6 were affected, negative factors led to impaired functionality of the primary bundle, Erba-Duchenne paralysis is diagnosed. This situation provokes the impossibility of the normal functionality of the axillary nervous tissue, muscle, skin. To some extent, the radial nerve loses its function. Such paralysis is noted by the following clinical symptoms:
- muscles atrophy;
- muscle tissue weakens;
- the proximal arm first suffers;
- brushes, fingers continue to function.
What else happens?
The situation of damage to the plexus nerve tissue, called Dejerine-Klumpke paralysis, is relatively well studied in medicine. The name is applied to pathology in which there is a defeat of the roots of C8-Th1. Similar symptoms will be in the case of inhibition of the functionality of the primary beam. With pathology, a loss of functionality (full or partial) of the nervous tissue of the shoulder, skin of the forearm, and shoulder is noted. Often the situation is accompanied by negative dynamics of the development of the median nerve. Clinical symptoms:
- small carpal muscles weaken, atrophy;
- carpal, finger flexors weaken, atrophy.
Another fairly widespread degenerative process is the inhibition of the functions of the primary beam in the center, the root C6. Both situations are manifested by a violation of the functionality of the radial nerve, and the degree of damage varies from the loss of some functions to a complete loss of performance. Additionally, in such a situation, degradation of the median nerve develops.
Where did the trouble come from?
Statistics show that problems associated with the functioning of the brachial plexus, in the vast majority of cases, are provoked by trauma to this area. Much less often, the cause is tissue infection, toxicosis, allergic reactions accompanied by infection. Injuries accompanied by stem breaks in the plexus are often observed with neck wounds. In a certain percentage of cases, this is diagnosed in infants, with damage accompanying the process of extraction from the birth canal. Perhaps the development of pathologies against the background of a clavicular fracture, a violation of the integrity of the head of the bone of the shoulder.
It is important!
An increase in the likelihood of compression damage, ischemic, accompanies a certain lifestyle. The risk of such a pathology is higher in people who:
- carry heavy loads on straps for a long time, which leads to crushing the area under the armpits;
- sleeping with hands behind his head;
- use crutches, webbing (against the background of the extension of the spinal column);
- suffer from tumor processes that have a compression effect on the neck, spinal table, lungs;
- suffer from aneurysm of the arteries under the armpits, under the collarbone;
- forced to fight with pathology - cervical ribs.
Dangerous situations
Infection of the brachial plexus is possible against the background of angina, flu, syphilis. There is a high level of danger for people diagnosed with tuberculosis, brucellosis. There is a chance of developing infectious allergic processes due to vaccination. The poisoning of the body with alcoholic beverages, carbon monoxide, heavy metals (lead, arsenic) can have a negative effect.