The musculoskeletal system performs a function. Musculoskeletal system. The value of the musculoskeletal system
All organs of motion that ensure the movement of the body in space are combined into a single system. It includes bones, joints, muscles and ligaments. The human musculoskeletal system performs certain functions, due to the peculiarities of the formation and structure of the organs of movement.
The value of the musculoskeletal system
The human skeleton performs several vital functions:
- support;
- protective;
- provides movement;
- takes part in hematopoiesis.
Violation of the musculoskeletal system causes pathological processes in the work of many body systems. The muscles attached to the bones move them relative to each other, which ensures the movement of the body in space. The muscular apparatus has its own functional feature:
- surrounds the cavities of the human body, protecting them from mechanical damage;
- perform a supporting function, supporting the body in a certain position.
In the process of development of the human musculoskeletal system, the development of the central nervous system is stimulated. The development of muscles and nerve cells are mutually dependent processes. Knowing what functions of the musculoskeletal system are necessary for the normal functioning of the body, we can conclude that the skeleton is a vital structure of the body.
During the period of embryogenesis, when practically no irritants affect the body, fetal movements cause irritation of muscle receptors. From them, impulses go to the central nervous system, stimulating the development of neurons. At the same time, the developing nervous system stimulates the growth and development of the muscular apparatus.
Skeleton anatomy
Skeleton - a set of bones that perform supporting, motor and protective functions. The human musculoskeletal system has about 200 bones (depending on age), of which only 33-34 bones are unpaired. There are axial (thorax, skull, spine) and additional (free limbs) skeletons.
Bones are formed by a type of connective tissue. It consists of cells and a dense intercellular substance, which contains many mineral components and collagen, which provides elasticity.
The skeleton is a container for vital human organs: the brain is located in the skull, the spinal cord is in the spinal canal, the chest protects the esophagus, lungs, heart, main arterial and venous trunks, and the pelvis protects the organs of the genitourinary system from damage. Violation of the musculoskeletal system can cause damage to internal organs, sometimes incompatible with life.
The structure of the bones
In the bones, a spongy and compact substance is secreted. Their ratio varies depending on the location and functions of a certain part of the musculoskeletal system.
The compact substance is localized in the diaphysis, which provide support and locomotor functions. Spongy substance is located in flat and short bones. The entire surface of the bone (with the exception of the articular) is covered with periosteum (periosteum).
Bone formation
In ontogenesis, the formation of the musculoskeletal system goes through several stages - membranous, cartilaginous and bone. From the second week after conception, cartilaginous rudiments form in the mesenchyme of the membranous skeleton. By the 8th week, cartilage is gradually replaced by bone.
Replacement of cartilage tissue with bone can take place in several ways:
- perichondriacal ossification - the formation of bone tissue along the perimeter of the cartilage;
- periosteal ossification - the production of young osteocytes by the formed periosteum;
- enchondral ossification - the formation of bone tissue inside the cartilage.
The process of formation of bone tissue consists in the germination of blood vessels and connective tissue from the periosteum into the cartilage (in these places, cartilage is destroyed). Spongy bone subsequently develops from some of the osteogenic cells.
During the period of intrauterine development of the fetus, ossification of the diaphysis of tubular bones occurs (ossification points are called primary), then after birth, epiphyses of tubular bones ossify (secondary ossification points). Until the age of 16-24 years, a cartilaginous epiphyseal plate is preserved between the epiphyses and diaphyses.
Due to its presence, the organs of the musculoskeletal system are lengthened. After the bone is replaced and the fusion of the diaphyses and epiphyses of the tubular bones occurs, human growth stops.
The structure of the spinal column
The spinal column is a succession of overlapping vertebrae that are connected by intervertebral discs, joints and ligaments that form the basis of the musculoskeletal system. The functions of the spine are not only to support, but also to protect, preventing mechanical damage to the internal organs and the spinal cord passing through the spinal canal.
There are five sections of the spine - coccygeal, sacral, lumbar, thoracic and cervical. Each department has a certain degree of mobility, only the sacral spine is completely immobile.
The movement of the spine or its departments is provided with the help of skeletal muscles. The correct development of the musculoskeletal system in the neonatal period provides the necessary support for the internal organs and systems and their protection.
The structure of the chest
The thorax is a bone and cartilage formation consisting of the sternum, ribs and 12 thoracic vertebrae. The shape of the chest resembles an irregular truncated cone. The chest has 4 walls:
- anterior - formed by the sternum and cartilage of the ribs;
- posterior - formed by the vertebrae of the thoracic spine and the posterior ends of the ribs;
- 2 lateral - formed directly by the ribs.
In addition, there are two openings of the chest - the upper and lower apertures. The organs of the respiratory and digestive systems (esophagus, trachea, nerves and vessels) pass through the upper opening. The lower aperture is closed by the diaphragm, in which there are openings for the passage of large arterial and venous trunks (aorta, inferior vena cava) and the esophagus.
The structure of the skull
The skull is one of the main structures that forms the musculoskeletal system. The functions of the skull are to protect the brain, sensory organs and support for the initial sections of the respiratory and digestive systems. It consists of paired and unpaired bones and is divided into brain and facial sections.
The facial region of the skull consists of:
- from the maxillary and mandibular bones;
- two nasal bones;
The brain part of the skull includes:
- paired temporal bone;
- paired sphenoid bone;
- steam room;
- occipital bone.
The brain department performs a protective function for the brain and is its receptacle. The facial section provides support for the initial section of the respiratory and digestive systems and the sense organs.
Musculoskeletal system: functions and structure of the limbs
In the process of evolution, the skeleton of the limbs acquired extensive mobility due to the articular articulation of the bones (especially the radial and carpal joints). Allocate the chest and pelvic belts.
The upper belt (thoracic) includes the scapula and two bones of the clavicle, and the lower (pelvic) is formed by the paired pelvic bone. In the free part of the upper limb, the following departments are distinguished:
- proximal - represented by the humerus;
- middle - represented by the ulna and radius;
- distal - includes the bones of the wrist, metacarpal bones and bones of the fingers.
The free part of the lower limb consists of the following sections:
- proximal - represented by the femur;
- middle - includes the tibia and fibula;
- distal - bones of the tarsus, metatarsal bones and bones of the fingers.
The skeleton of the limbs provides the possibility of a wide range of actions and is necessary for normal work activity, which is provided by the musculoskeletal system. It is difficult to overestimate the functions of the skeleton of free limbs, since with their help a person performs almost all actions.
The structure of the muscular system
Skeletal muscles are attached to bones and, when contracted, provide movement of the body or its individual parts in space. Skeletal muscles are based on striated muscle fibers. In addition to supporting and motor functions, the muscles provide the function of breathing, swallowing, chewing, take part in facial expressions, heat generation and articulation of speech.
The main properties of skeletal muscles are:
- excitability - the activity of muscle fibers is carried out under the influence of nerve impulses;
- conduction - from the nerve endings to the central nervous system, there is a rapid impulse conduction;
- contractility - as a result of the movement of a nerve impulse, contractility of the skeletal muscle is carried out.
The muscle consists of tendon ends (the tendons that attach the muscle to the bone) and the abdomen (consisting of striated muscle fibers). The coordinated work of the musculoskeletal system is carried out by the correct functioning of the muscles and the necessary nervous regulation of the muscle fibers.
The whole set of bones and their connections (joints, ligaments, muscles), coordinated by interconnected nervous structures - this is how the musculoskeletal system (musculoskeletal system, locomotor system) is characterized in anatomy. Acting as a protector of the internal organs, this apparatus undergoes heavy loads and is subject to age-related changes to a greater extent than other body systems. Violations of the functional ability of the musculoskeletal system lead to a deterioration in mobility, so it is important to prevent them at the very beginning.
What is the musculoskeletal system
The muscular frame, connected in a certain way with the bone skeleton through joints and tendons, is a musculoskeletal system. Thanks to the coordinated work of the central nervous system and the endings of the bone levers, the conscious mobility of all parts of the body is carried out. At the macroscopic level, the structure of bones can be represented as follows:
- periosteum - a dense tissue covering the tubular bones, the nerve endings coming from it penetrate inside through micro-holes;
- compact tissue - the substance of the cortical layer of the bone, provides storage of chemical elements;
- trabecular substance - a spongy tissue consisting of bony septa arranged in space in a certain way to ensure the safety of arterial channels and bone marrow.
Structure
Bones, in their totality, the skeleton, muscles and connective structures - this is what is part of the musculoskeletal system. The musculoskeletal system owes its name to the fundamental elements, which, in addition to the main components, include the following compounds:
- synarthrosis;
- joints;
- tendons;
- ligaments.
Active part of the musculoskeletal system
Muscles, diaphragm, and organ walls make up the active part of the locomotor system. Muscle fiber, consisting of contractile filaments, provides the function of movement of all parts of the musculoskeletal system, including facial expressions. Chemical energy under the influence of impulses of the brain and spinal cord is converted into mechanical energy, which ensures the mobility of the system.
Passive part
The skeleton, formed by bones of various types, is the passive part of the musculoskeletal system. The structural elements of this area are:
- scull;
- spine;
- chest (ribs and sternum);
- limbs (the upper ones consist of the bones of the forearm, shoulder, hand, the lower ones - of the bones of the femur, lower leg, foot).
Functions
You can understand what functions the system of organs of movement performs based on its name, but providing the ability to perform motor actions is far from an exhaustive list of all the functionality of the musculoskeletal system, which is described in the table:
| Functions of the musculoskeletal system | Significance for the body |
| Provides fixation of internal organs, muscles, tendons and ligaments |
|
| Protective | Prevents organ damage |
| Locomotive | Under the influence of nerve impulses, the interaction of bones and ligaments is achieved, setting the muscles in motion |
| Spring | Reduces the degree of stress on the ligaments during physical activity, reduces organ concussion |
| Hematopoiesis | Protects red bone marrow where new blood cells are made |
| metabolic | Participates in metabolic processes, provides a constant composition of the blood |
| Reserve | Formation of a reserve of mineral compounds |
Conditions for the correct formation of the musculoskeletal system
Despite the fact that the bones seem to be a permanent substance, they are renewed and changed throughout life. Every 10 years there is a complete replacement of the structural skeletal system, and certain conditions are necessary for the correct formation of its chemical composition. By adhering to the rules below, you can prolong the health of the musculoskeletal system and prevent the development of violations of the functionality of its departments:
- eating food containing sufficient amounts of calcium and phosphorus;
- ensuring the intake of vital vitamins in the body;
- maintaining muscle activity;
- stress level control;
- compliance with the rest regime;
- rejection of bad habits.
Musculoskeletal disorders
The causes that provoke the occurrence of disorders of the musculoskeletal system are divided into internal and external. Internal include those that affect the internal organs and systems, contributing to damage to bone tissue. This may be a lack of essential vitamins and minerals in the body (for example, rickets is a form of vitamin deficiency in which bone strength is lost, the cause is a lack of vitamin D). External causes are events uncontrolled by a person that affect the integrity of the bones of the musculoskeletal system, i.e. injury.
Incorrect body position during movement or at rest (posture) and flattening of the sole (flat feet) have a gradual but constant deforming effect on the locomotor system. All damages that lead to disorders of the musculoskeletal system can lead to the development of serious diseases if they are not eliminated in the early stages.
Diseases
Partial or complete restriction of one of the functions of the musculoskeletal system is a symptom of the disease. The reason for its appearance divides diseases into primary and secondary. If this pathology occurs due to violations of the locomotor system, then it is considered primary. Secondary are those diseases of the musculoskeletal system that are caused by concomitant factors. Symptoms, probable causes and suggested treatments are listed in the table:
| Name of the disease of the locomotor system | Symptoms of the disease | Causal factors | Method of treatment |
| Rheumatoid arthritis | Destructive processes of the connective tissue of small joints | Heredity, infections that affect the immune system | Surgery, therapy aimed at reducing pain |
| Inflammatory processes that occur in articular synovial bags | Injuries, repetitive mechanical damage | Antibiotic therapy, hormonal drugs |
|
| Immobility, bone fusion | Post-traumatic infectious lesions | Surgical treatment |
|
| Osteoarthritis (osteoarthritis) | Degeneration occurring in cartilage tissues, cartilage rupture | Age-related changes, genetic predisposition, consequences of injuries | Physiotherapy, therapeutic gymnastics |
| Inflammation of the muscles, accompanied by pain during muscle contraction | Hypothermia, susceptibility to prolonged muscle tension (sports loads, a certain type of activity) | Medical treatment with analgesics and painkillers |
|
| Tendinitis | Development of tendon dystrophy | Immunological infections, neurological disorders | Compression of the damaged area, in the chronic form, it is necessary to take analgesics and anti-inflammatory drugs |
| Osteoporosis | Violation of the structure of bone tissue at the microscopic level | Hormonal disruptions, exposure to bad habits, beriberi | Hormone therapy, taking vitamin-containing drugs |
Comprehensive approach to treatment
The appearance of the first pain sensations, feelings of discomfort during movements, should serve as a reason for contacting a doctor. Most diseases of all departments of the musculoskeletal system can be easily cured at the initial stage of the pathological process. Medicine offers a number of preventive and therapeutic measures aimed at improving the spine, among which the following are effective:
- acupuncture;
- manual massages;
- the impact of natural and artificially created factors (magnetotherapy, ultrasound, current, laser);
- physiotherapy;
- prosthetics and other types of surgical intervention;
- medications.
Video
Attention! The information provided in the article is for informational purposes only. The materials of the article do not call for self-treatment. Only a qualified doctor can make a diagnosis and give recommendations for treatment, based on the individual characteristics of a particular patient.
Did you find an error in the text? Select it, press Ctrl + Enter and we'll fix it!The musculoskeletal system is often referred to as the musculoskeletal system because the skeleton and muscles function together. They determine the shape of the body, provide supporting, protective and motor functions.
— the most active part of the musculoskeletal system, they are attached to the skeleton and control all human movements, because they can contract.
The bones act as passive levers.
Most of the bones of the skeleton are connected movably with the help of joints. The muscle is attached at one end to one bone that forms the joint, the other end to another bone. When a muscle contracts, it sets the bones in motion. Thanks to the muscles of the opposite action, the bones can not only make certain movements, but also be fixed relative to each other.
Bones and muscles take part in metabolism, in particular in the exchange of phosphorus and calcium.
FUNCTIONS
support the function is manifested in the fact that the bones of the skeleton and muscles form a strong frame that determines the position of the internal organs and does not allow them to move.
Protective the function is performed by the bones of the skeleton, which protect organs from injury. So, the spinal cord and the brain are in the bone "case": the brain is protected by the skull, the spinal cord - by the spine.
The ribcage covers the heart and lungs, the airways, the esophagus, and large blood vessels. The organs of the abdominal cavity are protected from behind by the spine, from below by the pelvic bones, and from the front by the abdominal muscles.
Motor the function is possible only if the muscles and bones of the skeleton interact, since the muscles set the bone levers in motion.
CHEMICAL COMPOSITION OF BONES
The chemical composition of human bone consists of:
- organic matter
- Minerals
Bone flexibility depends on the presence of organic substances, hardness - on inorganic ones.
The strongest bones in a person in his adulthood (from 20 to 40 years).
In children, the proportion of organic matter in the bones is relatively large. Therefore, children's bones rarely break. In older people, the proportion of minerals in the bones increases. Therefore, their bones become more brittle.
TYPES OF BONES
According to the type of structure, they distinguish:
- Tubular
- Spongy
- flat bones
Tubular bones: serve as long, strong levers, due to which a person can move in space or lift weights. The tubular bones include the bones of the shoulder, forearm, thigh and lower leg. The growth of tubular bones is completed by the age of 20-25.
Spongy bones: mainly serve as a support function. Spongy bones include the bones of the vertebral bodies, sternum, small bones of the hand and foot.
Flat bones: perform mainly a protective function. Flat bones are the bones that form the vault of the skull.
MUSCLES
Skeletal muscles are able to act only on signals coming from the central nervous system.
The energy necessary for contraction is released during the breakdown and oxidation of the organic substances of the muscle fiber itself. In this case, energy-rich compounds are formed that can restore muscle fibers during rest.
When working close to the limit, good nutrition and sufficient rest, the formation of new substances and structures in muscle fibers overtakes decay.
Due to this, a training effect occurs: the muscle becomes more powerful and more efficient. The low mobility of a person - hypodynamia - leads to a weakening of the muscles and the whole organism as a whole.
DISEASES OF THE musculoskeletal system
Hypodynamia is not the only reason that causes disturbances in the skeleton. Improper nutrition, lack of vitamin D, parathyroid diseases - this is not a complete list of reasons that disrupt skeletal function, especially in children. So, with a lack of vitamin D in the diet, the child develops rickets.
At the same time, the intake of calcium and phosphorus into the body decreases, as a result of which the bones of the legs are bent under the influence of the gravity of the body. Due to improper ossification, thickenings are formed on the ribs, heads of the digital bones, and the normal growth of the skull is disturbed.
With rickets, not only the skeleton suffers, but also the muscles, endocrine and nervous systems. The child becomes irritable, whiny, shy. Vitamin D can be formed in the body under the influence of ultraviolet rays, so sunbathing and artificial irradiation with a quartz lamp prevent the development of rickets.
The cause of joint disease can be foci of purulent infection with lesions of the tonsils, middle ear, teeth, etc. Influenza, tonsillitis, severe hypothermia may precede the disease of one or more joints. They swell, hurt, movements in them are difficult. In the joints, the normal growth of bone and cartilage tissue is disturbed, in especially severe cases, the joint loses its mobility. That is why it is important to monitor the condition of the teeth, throat and nasopharynx.
Joints can also be damaged by overtraining. With prolonged skiing, running, jumping, thinning of the articular cartilage occurs, sometimes the knee menisci suffer. In the knee joint between the femur and tibia are cartilaginous pads - menisci.
Each knee joint has two menisci - left and right. Inside the cartilaginous meniscus is fluid (). It absorbs the sharp shocks that the body experiences during movement. Violation of the integrity of the meniscus causes severe pain and severe lameness.
OUR MUSCULOCUTE SYSTEM LOVES:
OUR musculoskeletal system DOES NOT LIKE:
- Sedentary and sedentary lifestyle which leads to muscle atrophy.
- Poor nutrition, due to which there is a shortage of micro- and macro-elements, in particular calcium and silicon.
- Excess weight.Excess weight puts an excessive load on the joints, as a result of which they wear out very quickly.
- Injuries.Injuries contribute to prolonged and forced restriction of movement. As a result of which, not only muscles and joints begin to suffer, but also the proper production of joint fluid, or, as it is also called, synovial fluid.
There is also a faster method for determining flat feet. On the track, the center of the heel is connected to the center of the third toe, if the resulting segment does not intersect the track in its narrowest part, then there is no flatfoot.
Musculoskeletal Development
Growth in length and ossification of the skeleton goes up to 25 years, and in thickness up to 35 years.
Development of the musculoskeletal systemdepends on:
Complete nutrition: the presence of vitamins and mineral salts in food;
Human motor activity ... protrusions, tubercles are formed on the bones at the points of muscle attachment. This increases the contact surface of the muscle tendon with the bone, which contributes to the strength of attachment, + the periosteum is more abundantly supplied with blood, the bones grow faster.
The value of physical activity:
Necessary for its normal physical and mental development.
Lack of movement hypodynamia(decreased strength), adversely affects human health. The work of the heart and lungs is disrupted, resistance to diseases decreases, and obesity develops. To maintain motor activity, a person must constantly engage in physical labor, physical education, and sports.
The Importance of Muscle Training:
When working, the muscles are better supplied with blood. It brings more nutrients and oxygen to muscle cells.
Metabolic processes are constantly going on in the body. Part of the substances absorbed in the intestine goes to the construction of cell and tissue elements, to the synthesis of enzymes. The other part breaks down and oxidizes with the release of energy. These processes are closely related. The stronger the processes of decay and oxidation go, the more intensively new substances are created.
If there is a discrepancy between the intake of nutrients and energy expenditure, the excess of absorbed substances goes to the formation of fat. It is deposited not only under the skin, but also in the connective tissue, which often replaces specialized tissues (muscle, liver, etc.).
Consider what happens during intense muscular work. Intensive biological oxidation of organic substances leads to the formation of a large number of ATP molecules that are involved in the work of muscles. Muscular work occurs due to the breakdown of ATP molecules with the release of energy. After its completion, usually a significant supply of unused ATP molecules remains in the muscle fibers. Due to these molecules, the lost structures are being restored, and there are more of them than there were at the beginning of the work - this training effect. It occurs after intense muscular work, subject to sufficient rest and good nutrition. But everything has its limit. If the load is too intense, and the rest after it is not enough, then there will be no restoration of the destroyed and the synthesis of the new.
Consequently, the training effect will not always manifest itself, too little load will not cause such a breakdown of substances that could accumulate many ATP molecules and stimulate the synthesis of new structures, and too hard work can lead to a predominance of breakdown over synthesis and further exhaustion of the body. The training effect is given only by the load at which protein synthesis overtakes their breakdown.
=>with a successful workout: 1. the effort expended must be sufficient but not excessive; 2. after work, a mandatory rest is necessary, allowing you to restore what you have lost and acquire a new one.
An increase in muscle strength occurs with loads close to the limit, adequate nutrition and good rest.
Physical education and physical labor are the main conditions for a healthy lifestyle. At the same time, overloads cause serious harm to health, which is typical for big sport. Especially harmful dope, which allow you to get high results due to chemical intervention in the physiological processes occurring in the body.
Doping can be harmful both by side effects as chemicals, and by overloading, which can far exceed the body's capabilities.
Doping control only partially reduces the harm caused to the health of athletes, because. there is an intensive development of new doping agents that are not detected in the analysis.
Now medicine knows substances:
1. dope- they can sharply increase nervous and muscle strength for a short time. (For the first time, doping was given to horses participating in races. They really showed great agility, but after races they never restored their previous shape, most often they were shot.) In sports, the use of these substances Absolutely forbidden. An athlete who has taken doping has an advantage over those who have not taken it, and his results may turn out to be better not due to the perfection of technology, skill, labor, but due to taking the drug, moreover, doping has a very harmful effect on the body. A temporary increase in working capacity may be followed by a complete disability.
2. Drugs that stimulate the synthesis of muscle proteins after the action of loads, they are used in medicine, for example, in the restoration of muscle activity after the gypsum applied after a bone fracture has been removed. In sports, these substances are of limited use.
Target morning exercises only to move from sleep to wakefulness, increase blood circulation and respiration, increase efficiency.
Typically, charging includes five to ten exercises for various muscle groups. Charging begins with sipping, which helps to warm up the muscles, joints and ligaments. Then exercises are performed for the shoulder girdle, arms, torso, pelvic girdle and legs. Charging ends with running in place, walking and breathing movements that normalize blood circulation.
The complex of physical exercises usually includes static(“swallow”, “yogi poses”) and dynamic(movement) exercises.
Static exercises develop strength, endurance, the ability to work with a lack of oxygen, but they cannot develop speed, accuracy and purposefulness of movements. This is achieved by dynamic exercises => static and dynamic exercises complement each other.
The same set of exercises ceases to have an effect on the human body if it becomes habitual. Therefore, once a week, a set of exercises is usually updated.
The main task of physical education lessons at school is to teach the correct economical movements when walking, running, jumping, skiing and skating, working on sports equipment. But it is not often possible to get such a load that would give a training effect in physical education classes. Therefore, sports are essential. Of great importance for every person is the right choice of sport. In this case, one must proceed from one's anatomical and physiological prerequisites, abilities, age, and state of health.
By developing muscles, we also train the nervous system. Our movements become more precise, faster and more economical. Remember how awkward your first moves on skates, bikes were and how they became when you learned to skate well.
Physical exercises develop the chest, respiratory muscles, strengthen the heart, improve the functioning of the digestive system.
Swimming is good in summer. Swimming works all muscle groups. Swimming is a great way to massage the body and harden the body. It makes a person resistant to colds. Be sure to go skiing in winter.
During the ski run, the muscles of the legs, arms, back work, the circulatory, respiratory and nervous systems are strengthened.
Useful for muscle training and a variety of physical labor: work in the garden and garden, cleaning the classroom and apartment.
The human musculoskeletal system is a combination of skeletal bones, cartilage tissue and ligaments attached to them, muscles, which together ensure the maintenance of a posture, movement, and the performance of active movements.
The structure of the musculoskeletal system
Bones, ligaments, muscles, joints are the organs of the musculoskeletal system.
Skeleton- a collection of bone elements that differ in structure and size. An adult human has 205 to 207 bones. In the structure, an organic part is distinguished (30% - osteocytes, collagen fibers) and inorganic (microelements Ca, phosphorus - 70%). Bones are divided into:
- Tubular(femoral, humerus, bones of the hand, feet, etc.) have two edges (epiphyses) and a central part - the diaphysis, in the transition zone in children there is a growth zone;
- flat(scapular bone, sternum) are surrounded by a compact plate.
- spongy(for example, vertebral bodies) - strong, compact, with little bone mobility;
- mixed- temporal bones, base of the skull.
Bones are united into an integral system through joints, tendons, muscles. There are two types of connections. When the bones are placed side by side and do not form a gap, this is a continuous method (fusion of the pelvic bones, attachment of the ribs to the sternum). If a gap remains between the two bone surfaces, this is an intermittent method. This form of connection is called a joint.
The internal skeleton is divided into the skeleton of the head, trunk, limbs.
Head skeleton
It is divided into the brain and facial skull. Bone elements of the brain: two pairs of temporal and parietal bones, single - occipital and frontal. They are securely articulated and immobilized. Os temporale (temple) contains the organs of the auditory apparatus. In the back of the head there is a hole (foramen occipitale magnum), where the spinal cord connects to the main one.
The bones of the facial skull are united immovably by sutures, among them only the mandibular bone is movable.
Torso skeleton
Consists of the spine and bony structures that form the chest. The spinal column has 32 to 34 vertebrae. There are VII cervical, XII thoracic, V lumbar, V sacral, connected to the sacrum, and III-V coccygeal vertebrae, which together form the coccyx.
Sternum has 3 components: handle, body and xiphoid process.
ribs- arcuate bones, having a long part (bone tissue) and a short part (cartilaginous).
Vertebra consists of a body, an arcuate part, two legs, one spinous process, two transverse and four articular. The body, arch and pair of legs form the vertebral foramen, their combination forms a cavity in the spine, where the spinal cord is located.
Upper limb skeleton
This includes the bone structures of the shoulder girdle and the free upper limb. The shoulder girdle is the connection of the clavicle and scapula with the help of the acromioclavicular joint.
Bones of the free upper limb:
- Brachial bone;
- radiation;
- elbow;
- wrist bones;
- metacarpus;
- phalanges of fingers.
Skeleton of the lower extremities
Unites the pelvis and bones of the free lower extremities. The pelvis is a combination of two large pelvic bones connected behind the spine in the sacrum, and in front - between them.
The pelvic bone up to 16 years is divided into three components: the ilium, pubis and ischium, they are connected by cartilaginous tissue. Over time, cartilage elements are replaced by bone. So at an older age, a person already has a solid pelvic bone.
Bones of the free lower limb:
- Femur;
- fibula;
- tibial;
- tarsus;
- metatarsal bones;
- phalanges of fingers.
musculature
Musculature - an indispensable component of the musculoskeletal system, includes striated and smooth muscles. Due to the presence of skeletal muscles, a person can perform a variety of movements, and smooth ones serve as an integral part of the shells of internal organs.
Muscle activity is an alternating contraction and relaxation of fibers, which occurs under the influence of the central nervous system, which sends impulses to muscle structures.
Muscles secrete:
- The central part, which performs the contractile function (abdomen), is built from striated muscles;
- distal parts, they do not contract - these are tendons, formations from parallel bundles of collagen fibers. They are very durable and low stretch. Due to the presence of tendons, muscles can attach to bone structures.
Muscles are divided into respiratory, chewing, facial.
Depending on the action performed, there are:
- Flexors - located on the front surface of the joint;
- extensors - located on the back surface of the joint;
- supinators, pronators - go obliquely or transversely in relation to the vertical axis of the limb;
- abductor muscles - located outside the joint;
- leading - lie inward from the articular surface.
Diseases of the musculoskeletal system
Inflammatory diseases:
- Arthritis is an inflammatory process of the joints;
- bursitis - inflammation of the periarticular bag;
- myositis - chronic inflammation of muscle tissue;
- osteomyelitis - the focus of inflammation is located in the bone marrow.
Degenerative-dystrophic diseases:
- Osteochondrosis - in the area of intervertebral discs, bone tissue and cartilage are destroyed;
- osteoporosis - dystrophic changes in bones after fractures;
- spondylosis - compaction of the surface layer of the vertebrae.
Traumatic diseases:
- Fractures of tubular bones, vertebrae, separation of ribs from the sternum, TBI with crushing of the bones of the skull, and others;
- stretching and rupture of tendons;
- bruises, damage to muscle fibers;
- displacement of bone surfaces in the joint - dislocations and subluxations of the shoulder, fingers, ankle, ankle, etc.
Rachiocampsis. Due to a violation of posture, the consequences of injuries develop scoliosis - a lateral deviation of the spinal column.
Flat feet - change in the shape of the foot, through the omission of its arches.
congenital deformities arms, legs, skull.
The meaning and functions of the musculoskeletal system
The importance of the musculoskeletal system in human life cannot be overestimated. Many important functions are assigned to muscles, bone structures, joints.
Protective. Bones and muscles protect internal organs from injury. The heart, lungs are surrounded by a powerful frame, dorsal and pectoral muscles, the genitourinary organs are located between the pelvic bones, which prevents the impact of adverse factors. The spinal cord is reliably protected by the medullary canal, and the hemispheres of the main brain - by the cranium.
Motion. The movement of a person is possible with the friendly work of the striated muscles, bone elements, their joints and ligaments. What is the role of skeletal muscles in the musculoskeletal system? Bones are able to carry out active movements only with the participation of attached muscles, to which nerve impulses go.
hematopoiesis. The body of long bones, the flat bones contain the germs of hematopoiesis, which is responsible for the creation of blood cells and the immune system.
Depot of microelements. Osteocytes are involved in the metabolic processes of mineral compounds of calcium, phosphorus, muscles - in the metabolism of glucose, lipids, proteins.
Depreciation. While running, jumping, falling, the friction of the surfaces is softened, the load is reduced.