The knee joint, along with the hip joint, is the largest and most powerful joint in the human skeleton. It unites the bones of the thigh and lower leg, which provide range of motion when walking. The joint has a complex complex structure, in which each element ensures the functioning of the knee in particular and the ability to walk in general.

The structure of the human knee joint explains the cause of emerging pathologies and helps to understand the etiology and course of inflammatory and degenerative diseases. Even small deviations from the norm in any element of the joint can cause pain and limited mobility.

Anatomy

Three bones of the knee joint are involved in the formation of the joint: the femur, tibia and patella. Inside the joint, on the tibial plateau, are located that increase the stability of the structure and ensure rational distribution of the load. During movement, the menisci spring - they compress and unclench, ensuring a smooth gait and protecting the articulation elements from abrasion. Despite not big size, the importance of the menisci is very great - when they are destroyed, the stability of the knee decreases and arthrosis inevitably occurs.

In addition to bones and menisci, the constituent elements of the articulation are the articular capsule, which forms the inversions of the knee joint and the synovial bursae, and ligaments. The ligaments that form the knee joint are formed by connective tissue. They fix bones, strengthen joints and limit range of motion. Ligaments provide stability to the joint and prevent movement of its structures. When injuries occur, ligaments are sprained or torn.

The knee is innervated by the popliteal nerve. It is located behind the joint and is part sciatic nerve, passing to the foot and lower leg. The sciatic nerve provides sensation and movement to the leg. The popliteal artery and vein are responsible for the blood supply, repeating the course of the nerve branches.

Structure of the knee joint

The main joint-forming elements are considered to be the following:

• condyles femur
• tibial plateau
• knee cap
• menisci
• joint capsule
• ligaments

The knee joint itself is formed by the heads of the femur and tibia. The head of the tibia is almost flat with a slight depression, and it is called a plateau, in which there is a medial part, located in the midline of the body, and a lateral part.

The head of the femur consists of two large rounded spherical protrusions, each of which is called the condyle of the knee joint. Located with inside the condyle of the knee joint is called medial (internal), and the opposite one is called lateral (external). The articular heads do not match in shape, and their congruence (correspondence) is achieved due to two menisci - medial and lateral, respectively.

The articular cavity is a gap that is limited by the heads of the bones, menisci and capsule walls. Inside the cavity there is synovial fluid, which ensures optimal gliding during movement, reduces friction of the articular cartilages and nourishes them. The surfaces of the bones entering the articulation are covered with cartilage tissue.

Hyaline cartilage of the knee joint is white, shiny, dense, 4-5 mm thick. Its purpose is to reduce friction between articular surfaces during movement. Healthy knee joint cartilage has a perfectly smooth surface. Various diseases (arthritis, arthrosis, gout, etc.) lead to damage to the surface of hyaline cartilage, which, in turn, causes pain when walking and limited range of motion.

Knee cap

The sesamoid bone, or patella, covers the front of the knee joint and protects it from injury. It is located in the tendons of the quadriceps muscle, has no fixation, is mobile and can move in all directions. Top part The patella has a rounded shape and is called the base, the elongated lower part is called the apex. On the inside of the knee is the pes anserine - the junction of the tendons of the 3 muscles.

Joint capsule

The bursa of the knee joint is a fibrous sheath that limits the outside of the articular cavity. It is attached to the tibia and femur bones. The capsule has low tension, which ensures a large range of motion in the knee in different planes. The joint capsule nourishes the articulation elements, protects them from external influences and wear. The posterior section of the capsule, located on the inside of the knee, is thicker and resembles a sieve - blood vessels pass through numerous holes, and blood supply to the joint is ensured.

The capsule of the knee joint has two membranes: internal synovial and external fibrous. The dense fibrous membrane performs protective functions. It has a simple structure and is firmly fixed. The synovial membrane produces a fluid that is appropriately named. It is covered with small outgrowths - villi, which increase its surface area.

In places of contact with the bones of the articulation, the synovial membrane forms a small protrusion - inversion of the knee joint. In total, there are 13 inversions, which are classified depending on their location: medial, lateral, anterior, inferior, superior inversion. They enlarge the joint cavity, and when pathological processes serve as places for accumulation of exudate, pus and blood.

Knee joint bags

They are an important addition, thanks to which muscles and tendons can move freely and painlessly. There are six main bags, which look like small slit-like cavities formed by the tissue of the synovial membrane. Inside they contain synovial fluid and can communicate with the articulation cavity or not. Bags begin to form after a person is born, under the influence of loads in the area of ​​the knee joint. With age, their number and volume increase.

Biomechanics of the knee

The knee joint provides support for the entire skeleton, bears the weight of the human body and experiences the greatest load when walking and moving. It performs many different movements, and therefore has complex biomechanics. The knee is capable of flexion, extension and circular rotational movements. The complex anatomy of the human knee joint ensures its wide functionality, coordinated work of all elements, optimal mobility and shock absorption.

Pathologies of the knee joint

Pathological changes in the musculoskeletal system can be caused by congenital pathology, injuries and diseases. The main signs indicating the presence of violations are:

• inflammatory process;
• painful sensations;
• limitation of mobility.

The degree of damage to the elements of the articulation, coupled with the cause of their occurrence, determines the localization and intensity of the pain syndrome. Pain can be diagnosed periodically, be permanent, appear when trying to bend/extend the knee, or be a consequence physical activity. One of the consequences of the ongoing inflammatory and degenerative processes is deformation of the knee joint, leading to serious illnesses up to disability.

Anomalies of the development of the knee joint

There is valgus and varus deformity of the knee joints, which can be congenital or acquired. The diagnosis is made using an x-ray. Normally, the legs of a standing person are straight and parallel to each other. With valgus deformity of the knee joint, they are curved - on the outside, an open angle appears in the knee area between the lower leg and the thigh.

The deformity may affect one or two knees. With bilateral curvature, the legs resemble the letter “X” in shape. Varus deformity of the knee joints bends the bones in the opposite direction and the shape of the legs resembles the letter “O”. With this pathology, the knee joint develops unevenly: the joint space decreases on the inside and widens on the outside. Then the changes affect the ligaments: the outer ones stretch, and the inner ones atrophy.

Each type of curvature is a complex pathology requiring complex treatment. If left untreated, the risk of excessive knee mobility, habitual dislocations, severe contractures, ankylosis and spinal pathologies is quite high.

Valgus and varus deformity in adults

It is an acquired pathology and most often appears with deforming arthrosis. In this case, the cartilage tissue of the joint undergoes destruction and irreversible changes, leading to loss of mobility of the knee. Also, deformation can be a consequence of injuries and inflammatory-degenerative diseases that cause changes in the structure of bones, muscles and tendons:

• compound fracture with displacement;
• ligament rupture;
• habitual knee dislocation;
• immune and endocrine diseases;
• arthritis and arthrosis.

In adults, treatment of a deformed knee joint is inextricably linked to the underlying cause and is symptomatic. Therapy includes the following points:

1. painkillers;
2. NSAIDs - non-steroidal anti-inflammatory drugs;
3. glucocorticosteroids;
4. vasoregulating drugs and venotonics;
5. chondroprotectors;
6. physiotherapeutic treatment;
7. massage.

Drug treatment is aimed at eliminating pain, restoring cartilage, improving metabolism and tissue nutrition, and maintaining joint mobility.

Valgus and varus deformity in children

Acquired varus or valgus deformity of the knee joints in children, which appears by 10-18 months, is associated with deviations in the formation musculoskeletal system child. As a rule, the deformity is diagnosed in weakened children with muscle hypotonia. It appears as a result of stress on the legs against the background of a weak muscular-ligamentous system. The cause of such a deviation may be prematurity of the child, intrauterine malnutrition, congenital weakness of connective tissue, general weakness of the body, or previous rickets.

The cause of the secondary pathology that causes abnormalities in the formation of the knee joint is neuromuscular diseases: polyneuropathy, cerebral palsy, muscular dystrophy, poliomyelitis. Deformation of the joint not only causes curvature of the legs, but also has an extremely detrimental effect on the entire body.

Quite often the feet and hip joints suffer, and with age, flat feet and coxarthrosis develop.

Treatment of hallux valgus and varus deformity in children includes:

• load limitation;
• wearing orthopedic shoes;
• use of orthoses and splints;
• massage;
• physiotherapy, most often paraffin wraps;
• physical therapy classes.

Conclusion

Having a complex structure, the knee joint bears a large load and performs many functions. It is a direct participant in walking and affects the quality of life. Paying attention to your body and taking care of the health of all its constituent elements will help you avoid knee pain and maintain an active lifestyle for a long time.

The knee joint is the largest and most complex in its structure in the human body; its anatomy is extremely complex, because it must not only support the weight of the entire owner’s body, but also allow him to perform a wide variety of movements: from dance steps to the lotus position in yoga.

Such a complex structure, an abundance of ligaments, muscles, nerve endings and blood vessels makes the knee very vulnerable to various diseases and injuries. One of the most common reasons Injuries to this particular joint cause disability.

It consists of the following formations:

1. bones - femur, tibia and patella,
2. muscles,
3. nerve endings and blood vessels,
4. menisci,
5. cruciate ligaments.

The knee joint in its structure is close to hinge joints. This allows not only to bend and straighten the lower leg, but also to perform pronation (inward rotation) and supination (outward movement), turning the bones of the lower leg.

Also, when flexing, the ligaments relax, and this makes it possible not only to rotate the lower leg, but also to make rotational and circular movements.

Bone components

The knee joint consists of the femur and tibia, these tubular bones are connected to each other by a system of ligaments and muscles, in addition, in the upper part of the knee there is a rounded bone - the patella or kneecap.

The femur ends in two spherical formations - the femoral condyles and, together with the flat surface of the tibia, form a connection - the tibial plateau.

bone components of the knee

The patella is attached to the main bones by ligaments and is located in front of the kneecap. Its movements are ensured by sliding along special grooves on the femoral condyles - the pallofemoral recess. All 3 surfaces are covered with a thick layer of cartilage tissue, its thickness reaches 5-6 mm, which provides shock absorption and reduces thorns during movement.

Connecting components

The main ligaments, together with the bones that make up the knee joint, are the cruciate ligaments. In addition to them, on the sides there are lateral collateral ligaments - medial and lateral. Inside there are the most powerful connective tissue formations - the cruciate ligaments. The anterior cruciate ligament connects the femur and the anterior surface of the tibia. It prevents the tibia from moving forward during movement.

The posterior cruciate ligament does the same thing, preventing the tibia from moving posterior to the femur. Ligaments provide connection between bones during movement and help to maintain it; rupture of the ligaments leads to the inability to make voluntary movements and lean on the injured leg.

In addition to the ligaments, the knee joint contains two more connective tissue formations that separate the cartilaginous surfaces of the femur and tibia - the menisci, which are very important for its normal functioning.

Menisci are often called cartilage, but in their structure they are closer to ligaments. Menisci are rounded plates of connective tissue found between the femur and the tibial plateau. They help to correctly distribute the weight of a person’s body, transferring it to a large surface and, in addition, stabilize the entire knee joint.

Their importance for the normal functioning of the joint is easy to understand by looking at the structure of the human knee - the photo makes it possible to see the menisci located between the spherical epiphysis of the femur (lower part) and the flat surface of the tibia.

Knee muscles

The muscles located around the joint and ensuring its functioning can be divided into three main groups:

• anterior muscle group - hip flexors - quadriceps and sartorius muscles,
• posterior group – extensors – biceps, semimembranosus and semitendinosus muscles,
• medial (inner) group – hip adductors – thin and adductor magnus muscles.

knee muscles

• One of the most powerful muscles in the human body is the quadriceps. It is divided into 4 independent muscles, located on the front surface of the femur and attached to the kneecap. There, the muscle tendon turns into a ligament and connects to the tibial tuberosity. The intermedius muscle, one of the branches of the quadriceps muscle, also attaches to the knee capsule and forms the knee muscle. Contraction of this muscle promotes leg extension and hip flexion.
• The sartorius muscle is also part of the muscles of the knee joint. It starts from the anterior iliac axis, crosses the surface of the femur and goes along the inner surface to the knee. There it goes around it from the inside and attaches to the tuberosity of the tibia. This muscle is two-part and therefore participates in flexion of both the thigh and lower leg, as well as in the inward and outward movement of the lower leg.
• Thin muscle - starts from the pubic joint, goes down and attaches to the knee joint. It helps with hip adduction and ankle flexion.

In addition to these muscles, the tendons of the biceps femoris, tendinous, semimembranosus and popliteus muscles pass through the knee joint. They provide adducting and abducting movements of the lower leg. The popliteus muscle is located directly behind the knee and helps with flexion and internal rotation.

Innervation and blood supply of the knee

The knee joint is innervated by branches of the sciatic nerve, which is divided into several parts and innervates the lower leg, foot and knee. The knee joint itself is innervated by the popliteal nerve, it is located behind it, and is divided into the tibial and peroneal branches.

The tibial nerve is located on the back of the leg, and the peroneal nerve is located in front. They provide sensory and motor innervation to the lower leg.

The blood supply to the knee joint is carried out using the popliteal arteries and veins, whose course follows the course of the nerve endings.

What are the risks of injury?

Depending on which component of the knee is damaged, injuries, diseases and pathologies are classified. It can be:

• dislocations,
• fractures of the bones surrounding the joint,
• inflammatory and dystrophic diseases,
• damage to the tissues inside and around the joint, that is, cartilage, capsules, ligaments, as well as adipose tissue.

The site is for informational purposes only. Do not self-medicate. If you notice any symptoms of illness, consult your doctor. The drugs presented on the site have contraindications; before use, read the instructions or consult a specialist.

How does the human knee work?

Joints perform an important function in the body, allowing movement and flexibility. The anatomy of the knee joint is the most complex, but it is its injuries that are most common. From this point of view, it is necessary to consider the structure of the knees in more detail, revealing all possible secrets.

It is better to start looking at the structure of the knees with the bones, which are the main component of any joint. Three bones are involved in the formation of the knee:

• thigh (top);
• tibia (bottom);
• patella or kneecap.

The largest formation is the femur, more precisely, its two condyles. They are two rounded ends of the bone with smooth surfaces. There is space between them; there are ligaments in it, which will be discussed a little later.

Also, the tibia, or more precisely, the condyles, takes part in the structure of the knees. Their anatomy in humans is different from the thigh; they are flat, smooth and have a bulge in the middle. The smooth surfaces are also called plateaus; cartilaginous parts called menisci are located on them.

The last component is the patella, although in the knee joint it is considered the smallest, but in the body it is the largest sesamoid bone. There are such bones in the hands, they are additional levers and are located in the thickness of the tendon. The patella has two surfaces: one external, and the second internal, smoother, covered with cartilage. Also, the kneecap in humans has a base and a pole in the form of a narrowing at the bottom. Surrounded on all sides by ligaments, the cup moves easily.

Cartilaginous part

All articular surfaces are covered with cartilage, but between the condyles of the tibia and femur there are menisci. These are specific formations in the form of cartilage pads, in the joint one is internal and the other is external. During movements, they compress and shift; in addition, they eliminate the discrepancy between the articular surfaces in the joint.

But the anatomy of such a large and important joint as the human knee will be incomplete if we do not consider each meniscus individually. The external meniscus is a mobile formation, and therefore injuries are much less common. In contrast, the medial one is fixed by ligaments, its mobility is less, and the likelihood of injury increases.

Joint capsule

The knee capsule covers it on all sides, protects it and produces fluid that accumulates in the joint cavity. It is attached to the bone along the edge of the articular surface. Additional structures of the capsule are bags; they are of great importance in practical activities. In total, a person has six bursae in the joint, which are found in everyone. There are additional ones that vary.

The most basic are:

1. In front of the patella there is a bag with the corresponding name.
2. There is also a corresponding bag under the patella.
3. There is also a bursa in front of the patella; it is located under the skin.
4. A bursa of muscles is distinguished, which is called semimembranosus.
5. U popliteus also has its own bag.

Ligamentous apparatus

In order for the joint to have greater stability, there are ligaments; they are attached to the bones and are internal and external. It’s better to start looking at the internal ligaments, which are located in the joint cavity. The anterior ligament originates from the inner surface of the lateral condyle of the femur. Crossing the joint diagonally, it is strengthened in the intercondylar fossa. This ligament allows you to stabilize the knee, control the degree of displacement of the tibia, and holds the lateral condyle.

The posterior cruciate ligament originates from the internal condyle of the femur, crosses the joint obliquely and is also attached to the intercondylar fossa. This ligament additionally strengthens the internal meniscus, allows you to stabilize the knee, and supports the lower leg when it is displaced.

There is also a whole system of external ligaments, one of them is the lateral, or collateral. With the help of these ligaments, the lower leg does not move to the side; if their anatomy is disrupted, the knee becomes unstable.

The front of the knee is covered by a ligament, which is a continuation of the quadriceps muscle. It covers the patella, further stabilizing the person’s knee. This ligament is attached to the tibial tuberosity. The patella acts as a lever during movement; if this ligament is damaged, straightening the leg becomes problematic. There are also ligaments at the back of the knee joint, for example, the oblique one, and next to it there is the curved one.

The free space of the knee is filled with folds, or outgrowths of the joint capsule. In front of the patella in humans there are wing-shaped folds that fill the free space between the condyles of the femur and the menisci. In the back of the knee, a person also has its own folds; they are smaller in size.

Synovial fluid

The joint, like any mechanism, has synovial fluid in its cavity for better gliding. Its composition looks like ghee, and the amount is approximately equal to a tablespoon. It is a nourishing composition for cartilage, including the patella. While walking, a person’s cartilage contracts and then, like a sponge, absorbs useful substances.

When the production of joint fluid is disrupted, a person develops a disease called synovitis. The amount of liquid increases sharply and can reach significant volumes. At the same time, the capsule becomes very tense, the joint constantly hurts.

The muscles move the joint, the largest of them in front is the quadriceps, which is responsible for extension. Back group muscles that flex the knee joint. In the knee, ligaments limit other movements, which is why the joint moves only in one plane.

Popliteal fossa

Behind the knee there is an important formation, which is limited by muscles and ligaments, it is called the popliteal fossa.
Important anatomical formations are concentrated in this area, for example, the popliteal artery. She is a continuation femoral artery, and from it the vessels further extend to the lower leg. There are eight vessels in total that supply blood to the knee joint.

Also in this area there are large nerves, which are a continuation of the largest one - the sciatic one. There are also smaller branches that pass here and then go to the back of the lower leg. This place also contains lymphatic vessels; nodes are located next to them in this area, which can increase in size when infected.

The knee joint is the most complex joint in the human body, but it is the one that is often injured in everyday life. The knee contains in its cavity many important anatomical formations, if damaged, its function is disrupted, after which any person loses the ability to walk. Taking into account the structure, pathologies are diagnosed, and very often all kinds of damage, and this structure also helps to carry out surgical interventions.

Today, knee prostheses have been developed that allow a person to return to active life. However, over time, the implant will have to be changed, since, no matter how good it is, it is not capable of self-renewal. That is why you should take care of your joints from a young age and avoid injuries.

Functioning and structure of the knee joint

The structure of the knee joint is very complex, it includes a large number of ligaments, nerve fibers, blood vessels and muscles. The knee joint is the largest joint human body. It takes on a lot of load and makes it possible to reproduce the most complex actions: from ice skating to climbing trees.

The special structure of the human knee joint makes this joint vulnerable to injury and disease. Damage to the knee joint often causes disability and requires long-term treatment. The human knee is a collection of muscles, ligaments, nerves and blood vessels, bones and menisci. The action is similar to that of a ball joint. The lower leg can bend, straighten and rotate. Circular and rotational movements are made by the ligaments, which relax during the circular movement.

Joint-forming bones and ligaments

The knee joint is formed by two tubular bones. They are called femoral and tibial. The front of the knee is protected by a rounded bone called the patella.

The lower part of the joint is formed by two semicircular elevations of the femur - the condyles. The covering of the condyles consists of cartilaginous tissue. During movement, the condyles interact with a surface of the tibia called the tibial plateau.

This plateau is divided into two parts: medial (at the center of the body) and lateral. The kneecap moves along the patellofemoral recess formed by the femoral condyles.

How does the human knee work?

The thickness of the articular cartilage is 5-6 mm. Cartilage tissue covers the surface of the ends of the bones that make up the joint and the back of the kneecap. Cartilage has a smooth and shiny surface. This surface improves shock absorption and reduces friction between bones during movement.

The bones of the knee joint are fixed by connective tissue. To strengthen the joint capsule and prevent lateral movements, there are ligaments in the lateral parts: lateral and medial. Movement back and forth is controlled by the cruciate ligaments, which are located in the center of the knee joint. The tibia is held in place by the anterior cruciate ligament, which prevents the bone from sliding forward. To prevent the tibia from sliding backwards in relation to the femur, it is secured by the posterior cruciate ligament.

Menisci are cartilaginous formations

Between the ends of the bones there are menisci - cartilaginous formations. Menisci resemble cartilage tissue, but have a slightly different structure than the cartilaginous surface of the ends of bones. The function of the menisci is to provide stability to the knee joint and distribute body weight evenly over the surface of the tibial plateau.

The structure of the menisci is more elastic than the articular surface of the bones.

The menisci act as pads that help distribute body weight evenly over the surface of the tibia. If the menisci were absent, the plateau would experience excessive stress, and all the pressure would be placed on one point on the surface of the tibia. If the menisci are damaged, the cartilage begins to deform and the stability of the knee joint is impaired.

Structure of the knee meniscus

The thickness of the menisci in the central part is less than in the periphery. This structure forms a small depression on the surface of the tibial plateau, provides stability and allows the load to be distributed more evenly. The structure of the knee joint is formed by surfaces that cannot independently provide stability, as is the case in the hip or elbow joint. Therefore the ligaments play huge role in strengthening the joint, without them it would be unstable.

Surrounding muscles

The work of the joint is provided by the muscles located around it. Muscles, in turn, are divided into three groups:

What muscles fix the human knee?

• hip flexor muscles;
• hip extension;
• leading.

On the front of the thigh is the largest muscle in the human body - the quadriceps. The quadriceps muscle attaches to the kneecap and to the surface of the tibia. The knee muscle is formed from branches of the quadriceps muscle and is attached to the joint capsule. This muscle is responsible for the movements of the thigh and lower leg.

The sartorius muscle bends around the kneecap through the surface of the femur. It is then attached to the tibia. This muscle allows the lower leg to move back and forth.

The biarticular gracilis muscle originates at the pubic bone. In the form of a thin cord, it is attached to the tibia. This muscle, passing slightly to the side of the transverse axis, helps flex the joint.

The hamstrings help rotate the knee and flex the shin. There are semitendinosus muscles on the back of the thigh. Their work allows for rotational movements of the lower leg, extension movements of the thigh and lower leg. The gastrocnemius muscles begin at the condyles of the femur. These muscles are responsible for flexing the lower leg at the knee and ankle.

The function of the popliteus muscle is to pronate (rotate) the lower leg and flex it. This short and flat muscle is located on the back of the knee and begins at the lateral condyle.

Innervation and blood supply of the knee joint

The innervation pattern of the knee joint has many complex interweavings. Sensation is provided by the sciatic, tibial and peroneal nerves. The posterior part of the knee is innervated by the tibial nerve through articular branches. The anterior outer part of the patella is innervated by peroneal nerve, which passes under the biceps muscle.

The nerves in the menisci run along the periphery of the cartilaginous body. Nerve plexuses penetrate into the menisci with blood vessels. The nerve bundles of the menisci form pulpal and non-pulpate nerve fibers.

The nerve formations of the menisci are not very developed relative to other areas of human nerves. The knee joint, the structure of which is mechanically disturbed, is subject to dystrophic and necrobiotic changes. Sclerosis occurs after damage to the nerves in the capsule.

The circulatory system nourishes all elements of the joint. A network of anastomoses connects all the veins of the knee. The periarticular tissue contains a venous network consisting of veins emerging from the joint capsule. The largest vessels are located on the back. The popliteal vein provides peripheral blood flow, and the popliteal artery returns blood flow to the heart.

The outflow of blood through the deep veins is due to the presence of valves in the veins. Lymphatic vessels are located along the blood vessels. Lymphatic drainage from the anterior internal part is carried out to the large inguinal lymph nodes.

The lymphatic vessels of the anterior part enter the popliteal fossa and connect to the lymphatic popliteal nodes. From the back, the lymphatic vessels also flow into the network of lymphatic vessels of the popliteal fossa.

Most common injuries

The most common knee injury is a torn ligament.

The most common injury to the knee joint occurs in athletes (usually football players, skiers and wrestlers). This is a torn cruciate ligament. Ligaments are torn after a severe blow to the back of the knee. When the rupture is accompanied by fractures of the bony protrusions and fractures of the attachment points of the ligaments, treatment becomes very difficult. The posterior ligament can be damaged after a blow to the shin or when it is extended too sharply. The most severe form is the rupture of all ligaments, when the joint completely loses stability and its mobility deteriorates.

Ligament rupture is accompanied by severe pain. Blood begins to flow into the joint cavity. There are cases when the moment of injury itself is not noticeable, and symptoms of torn ligaments appear later when walking. The bones become too mobile, and “pushed-out drawer” syndrome occurs.

If the shin is twisted sharply, a meniscus fracture may occur. In case of injury or dislocation, it is important to limit the movement of the joint, apply an ice pack and consult a traumatologist. Such injuries are very dangerous and can lead to disability.

When the bones of the knee joint break, surgery is required in most cases.

A friend recently had knee surgery, I’ll send him this article so he can read it to avoid further problems.

Does anyone know if draining fluid from their knee is very painful? They prescribed this procedure, I’m terribly afraid.

I remember they did this to my grandmother, they pumped fluid out of her knee. It helped, she immediately felt better, otherwise she was in a lot of pain and had joint pain.

How to determine whether a ligament has been torn or just sprained?

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The knee joint is one of the largest and most complex in humans. The main actions of the knee joint are flexion and extension. lower limbs. The role of the knee joint cannot be underestimated, since full walking and normal life activities are impossible without its participation.

The knee joint consists of three main bones. Its structure is presented as follows:

• at the top is the femur;
• below – tibial;
• in front - the kneecap.

The tibia and femur have special extensions called condyles. There are internal and external condyles. The external condyle is called lateral (from Latin lateralis), the internal is called medial (in Latin medialis). The knee joint itself has a special coating - a capsule, which performs a protective function. Synovial fluid also plays an important role in the functioning of the joint, which covers the cartilage and bones and ensures smooth movement. All osteochondral structures of the human knee joint must be smooth, only in this case the leg will bend and work correctly. It is also worth noting that the knee joint is strengthened by ligaments that should not be damaged. The photo shows the anatomy of the knee joint.

The muscles that provide movement of this joint form three groups: medial, anterior and posterior. The medial muscles are thin and large conductive muscles. The thin one starts from the pubic bone, goes down and is attached to the tibia. The large muscle starts from the ischial tuberosity and is attached to the epicondyle of the femur. The posterior group is biceps, semitendinosus and semimembranosus. The anterior group is formed by the hip flexor muscles.

The anatomy of the human knee combines not only muscles, bones and tendons, but also synovial bursae. They provide gliding for muscles and tendons. The anatomy of the knee joint is complex. The bones here form a complex unit in the musculoskeletal system.

Why do painful sensations appear in the joints?

Pain in human knee joints can be inflammatory, dystrophic and traumatic. It is worth noting the fact that types of pain can be combined with each other. At the same time, it is very difficult to determine and confirm an accurate diagnosis, since the symptoms are complexly intertwined. In this case, the person will have to undergo a complete and thorough examination, since it is after the correct diagnosis is made that an objective and most accurate treatment can be prescribed.

Most often, there are two diagnoses for knee pain: arthritis and arthrosis. The first disease is an inflammatory process of various types in tissues and cartilage. Arthrosis is degeneration of intra-articular structures and tissues, often accompanied by pain in the muscles.

Rare pathologies

Rarely diagnosed diseases include the following:

1. Meniscopathy is a complex lesion of the knee meniscus, in which cysts form and the muscles become inflamed.
2. Presence of intra-articular foreign bodies.
3. Hoffa's disease - this disease affects fatty tissue, there is a strong inflammatory process, the muscles around the cup can also become inflamed.
4. Condylar dysplasia - most often leads to immobility of the patella and flabbiness of the adjacent muscle.
5. Bursitis - the periarticular capsule becomes inflamed, although no damage to intra-articular structures is observed.
6. Koenig's syndrome - osteochondritis.

All such lesions have much in common in their symptoms. Their treatment may be similar in some cases.

Symptoms of knee joint diseases

All diseases of the knee joint are characterized by severe and prolonged pain when walking, sometimes you can notice swelling and deformation in the affected area, the muscles become flabby and sore. Pain occurs when supporting or standing. Such pain is long-lasting and may not go away for quite a long time.

If speak about inflammatory diseases person, they can be characterized by edema, high temperature. Such diseases most often begin suddenly; they can be diagnosed by general analysis blood. Dystrophic diseases have hereditary and congenital prerequisites. Such diseases never develop suddenly; their formation always occurs gradually. Such diseases are chronic; over time, pain increases and symptoms worsen. It is these diseases that should be treated with special caution, because if they are not treated on time, then there is a risk of remaining disabled altogether.

Post-traumatic human diseases can be both dystrophic and chronic. However, they have one peculiarity - the cause is always a previous injury to the knee or muscle.

If there are prolonged and severe pain in the knee joint, you should never wait. You should immediately go to specialists. Like any disease, knee joint diseases should not be neglected. An initially correct diagnosis is the first step towards a quick and successful recovery. Treatment of diseases such as arthritis and arthrosis must be comprehensive. The doctor prescribes physical therapy, drug treatment, ointments and creams.

Treatment of tendinitis and bursitis

These diseases are less common than arthritis and arthrosis, but compared to other pathologies they are quite common. Treatment uses drug therapy, sometimes the joint capsule is punctured and excess fluid is removed from the joint, and the necessary antibiotics are administered. Folk remedies can also be used for treatment, but if the pain is severe, under no circumstances should you postpone a visit to a specialist.

Treatment of chondropathy, tendinopathy

These are diseases of a dystrophic nature. The success of treatment will depend, first of all, on a timely and correct diagnosis. Most often, drug treatment is not used here, since it makes absolutely no sense. To treat these diseases, the patient will most likely undergo surgery, after which the patient’s health will gradually improve.

Folk remedies

If it is impossible to visit a doctor, you can use proven folk remedies to relieve pain in the knee joints. To do this, you can use improvised means. Burdock and cabbage help well. They reduce pain and relieve inflammation. You can use Kalanchoe juice. For this method, you will need to cut off several leaves and place them in a cool place for several days. After which it is necessary to make compresses from the juice of the plant. It is best to do this procedure often, at least 6-7 times a day.

It is important to remember that to eliminate a disease, it is necessary to get rid of its origins and causes, and not just the symptoms. Folk remedies They will help reduce the inflammatory process and temporarily relieve pain, but they will not cure the disease itself. That is why it is important to contact specialists at the clinic at the slightest opportunity.

Disease Prevention

Any disease is much easier to prevent than to treat. If the disease is non-hereditary and non-congenital, then any person can prevent it. Diseases of the knee joints can be prevented by performing a set of special exercises. Such a complex should be developed purely individually, since any organism has its own characteristics. To develop a set of exercises, it is best to contact an experienced physiotherapist, who will not only create an individual program, but also help develop the knee joint. It is from him that you can learn about the features of prevention and carry out competent treatment using physiotherapeutic methods.

Every person tries in every possible way to protect himself from various diseases, because health is the main thing.

In order to avoid diseases, you need, first of all, to know the characteristics of the body.

In this article we will look at the structure of the knee joint.
The knee joint is classified as a trochlear joint, so it has one axis of movement that runs along the length of the joint itself.

The knee joint is one of the most complex systems in the body.

The structure of the human knee joint is one of the most complex systems of the body. It is formed by three bones: on top is the femur, on the bottom is the tibia, and in front is the kneecap, the structure of which is also quite complex.

It is the largest sesamoid bone in the human body.

The kneecap is located in the tendons of the quadriceps muscle. It can be felt without any problems. The kneecap can easily move laterally and move up or down. The upper part (base of the patella) of the cup has a rounded shape. The lower part (apex of the patella) has an elongated shape.
Almost the entire surface of the cup is slightly rough. At the back, the patella is divided into two asymmetrical parts: (medial and lateral). The main function of the cup is protective; it protects the joint from injury.

Menisci

The structure of the knee also includes menisci - peculiar layers (cartilage pads) that increase the stability of the joint. In other words, these are knee shock absorbers. They are located between the tibia and femur. When a person moves, the menisci of the knee joint change shape (compress).

Menisci are knee shock absorbers

Experts distinguish several types of meniscus of the knee joint:

• Lateral (sometimes called external). He is very mobile, and is less likely to be injured in the second type;
• Medial (internal). The meniscus is inactive and is connected to the collateral (internal) lateral ligament of the knee joint. This structure often causes joint and collateral joints.

Knee joint capsule

The system includes the knee joint capsule. This is a kind of fibrous case through which the bones contact each other. The shape of this capsule can be compared to an elongated cylinder, back wall which is concave inward.

The knee joint capsule is a kind of case

The articular capsule is attached to the tibia and femur.
The inner side of the capsule is called the synovium.

The structure of the knee joint is very well thought out by nature. It contains synovial fluid (lubricant for cartilage), which makes sliding painless.

It also nourishes cartilage with beneficial substances that slow down their wear.

Protrusions are formed from the upper and lower bones, which are called the condyle of the knee joint (internal and external). Their scientific name is lateral (external) and medial (internal) condyle.
The surface of the tibia, femur, and patella (kneecap), which are in contact with each other, is covered with smooth cartilage. This makes sliding easy.

Bursae of the knee joint

The muscles and ligaments of the knee joint form the tendons in which the patella is located.
A very important component of this structure is the bursa of the knee joint, thanks to which the muscles, tendons, and fascia can move freely and painlessly.
Scientists count six main bags, which include:

• Suprapatellar bursa;
• Deep subpatellar bursa;
• Subcutaneous prepatellar bursa;
• Bursa of the semimembranosus muscle;
• Bursa propria of the semimembranosus muscle;
• Bursa of the popliteus muscle.

The structure of the ligaments of the knee joint

When a ligament is injured, a person experiences discomfort and is unable to move or exercise normally. The ligaments of the knee joint and their anatomy are quite a complex system.
It includes the following elements:

1. Anterior cruciate ligament of the knee joint.

It begins on the inner femoral condyle. The ligament crosses the joint. At the end it is attached in the region of the intercondylar fossa. The cruciate ligament of the knee joint helps stabilize the knee joint and controls the movement of the tibia.

The ligaments of the knee joint and their anatomy are a complex system.

3. Collateral (internal) lateral ligament of the knee joint.

Experts distinguish three parts of this bundle:

• The upper one (has the largest size in the system of external ligaments. It is oval in shape, attached to the inside of the condyle. Closer to the bottom, the ligament is divided into two parts;
• Posterior (located behind the superior ligament, interacts with the semimembranosus muscle);
• Deep part of the ligament (connected to the inner part of the meniscus).

The medial collateral ligament of the knee joint normalizes the movement of the lower leg.

4. External collateral ligament.

In the lower part, the lateral ligament of the knee joint is connected to the fibula. It begins from the external condyle. When the leg is extended, the ligament is tense, and when the leg is bent, it is relaxed. It has no connection with the meniscus, because there is a fatty layer between them.
A little lower from the kneecap there is the so-called patellar ligament. It is attached to the tibia.

All of them provide a person with a normal life: walking, the opportunity to engage in physical exercise, while it is the ligaments that most often become the cause of various injuries to the knee joint.

Video about the anatomy of the knee joint.

Based on the above information, it can be argued that the knee joint has a very complex structure.

This part of the human body performs important functions: it allows you to bend and straighten your leg, and turn it to the sides.

Also, the knee allows a person to do many physical exercise and move around. In this case, the joint is the place that is most often susceptible to damage. First of all, this is due to the complex anatomy of the knee.

The knee joint in humans has a complex structure. It is designed to carry heavy loads. However, the knee joint, the structure of which seems to provide for everything, very often suffers various diseases. Diseases of the knee joint are not easy to treat; they can be associated with long-term increased loads on it due to excess weight, knee injuries, metabolic disorders in the human body, and lack of vitamins and microelements.

The anatomy of the knee is designed to avoid friction between the bones and soften impacts. In addition, the patella protects the knee from external influences. However, if you regularly exceed the permissible loads and do not take care of your joints, this can lead to various diseases.

The main parts of the knee are:

• bones and muscles: the main parts around which the entire structure is formed;
• menisci - play an important role in ensuring joint mobility;
• nerve endings and a network of blood vessels: revitalize the knee, making it sensitive to various influences;
• ligaments and cartilage: they are the connecting link between bones and muscles, bearing the entire load.

The structure of the knee joint is the most complex compared to other human joints, in addition, this joint is the largest of all joints - that is, the knee takes two first places at once: in complexity and in size. The complexity of the joint structure makes the treatment of diseases associated with it difficult.

The knee consists of three bones - the femur and the tibia, or simply the tibia; the bones are covered on top by the kneecap, which protects the joint. The knee joint connects these bones and provides their mobility, performing the main functions of the knee - flexion and extension.

Smooth cartilage allows one bone to slide comfortably over another when the knee bends. This cartilage covers those parts of the bones that come into contact with each other. It is part of all three component bones - the femur, tibia and patella or kneecap.

In addition to cartilage, menisci are located in the interosseous space. They are special layers that produce a smoothing and shock-absorbing effect under load, increasing the contact area. But unlike cartilage, menisci exist only between two main bones - the tibia and femur.

A special shell covers the entire joint from the outside. Its inner part is called the synovial bursa. This bag is filled with so-called joint fluid. This fluid is used to lubricate the cartilage, which further improves gliding and reduces stress and friction in the joint. But that's not all: synovial fluid has another purpose - it is nutrient for cartilage, providing and maintaining its unique properties.

The anatomy of the knee joint also includes the presence of ligaments. They are needed to ensure that the bones are securely fixed to each other and fit tightly to the meniscus. Such ligaments located in the knee are called cruciate because of their shape. The knee joint includes an anterior ligament, a posterior ligament and two lateral ligaments - the external and internal. If ligaments are damaged, they are treated with fixing bandages and rest.

As already mentioned, the knee joint consists of only three bones. The femur is located on top and bears the main load on the joint. The shinbone or tibia is located below and takes the load from the femur. It is called the tibia, so as not to be confused with another shin bone - the fibula, but it is not part of the joint, so we will simply call the tibia - the tibia. The third bone is the kneecap. This is a small bone with a somewhat rounded shape - it can be compared to a triangle with strongly rounded corners. This bone is often called the patella.

The femur has two projections that resemble the shape of a ball. These protrusions are called femoral condyles. The condyles thus cover the lower surface of the femur and come into contact with the upper surface of the tibia.

The surface of the tibia has a symbolic name - plateau. The full name is tibial plateau. It is made up of two halves - the almond and lateral plateau.

The integral parts of the joint are the patella and several synovial bursae located in different parts of the joint - they are filled with fluid and facilitate the movement of the muscles and tendons attached to them.

The design of the kneecap is such that it is designed to move along a special groove. This groove lies between the femoral condyles, which form it. The kneecap, while protecting the knee, is itself susceptible to damage. If a kneecap injury occurs, immediate treatment is required.

The cartilage covering the surfaces of the contacting parts of the bones has an average thickness of about 6 millimeters. Of course, in children this figure is lower than in adults. The cartilage has a white color and a smooth, as if polished, surface. Cartilage is elastic. They easily cope with friction, reducing it to nothing, and are damping elements of the joint. In the knee, cartilage covers all three bones.

Ligaments are dense connective tissue. They are needed to bind the bones that form the joint together. The literal ligaments are located on the side of the joint, and the so-called collateral ligaments also take their place there. In addition to the general strengthening of the joint, these ligaments serve to prevent bones from moving to the side of the joint.

The cruciate ligaments of the knee joint, anterior and posterior, connect the ends of the femur and tibia, ensuring their tight fit to each other. Cruciate ligaments also serve as limiters for bone movement in unnecessary directions. The anterior and posterior ligaments are also needed to prevent the main bones from moving relative to each other.

By providing control over the mobility of bones within the joint, the cruciate ligaments of the knee perform a very important task.

Stability of the bones in the joint is also achieved with the help of other ligament-like formations. These formations, called menisci, are located between the femur and shin bones where they protrude on both sides. In terms of their structure, cartilage and menisci, although similar in appearance to each other, are very different in their structure and perform different tasks.

Meniscal diseases that occur as a result of overuse or injury are difficult to treat. If the meniscus is damaged, surgery is required.

Menisci and their purpose

Menisci perform two basic functions:

• increase the area of ​​contact between the bones, thereby reducing the load, that is, the pressure per unit area of ​​the femur on the tibia;
• ensure a stable condition of the joint, helping the ligaments.

If the meniscus loses one of its functions, you must immediately consult a doctor for treatment.

The menisci are flexible cushions under the contacting surfaces of the bones and behave as if a spherical surface were resting on a flat surface covered with a cushion. In this case, the pillow to some extent repeats the roundness of the spherical surface - the meniscus behaves in a similar way.

Being such soft pads, the menisci also fill the voids that could have formed in the areas where the bones fit if there were no menisci. The space to be filled is between the condyles and the tibial plateau.

Thus, the presence of menisci ensures the distribution of the weight of the human body on the tibia in the best possible way, distributing the load over the entire surface of the tibia plateau. Otherwise, if nature had not provided the meniscus in the design of the joint, the entire load would fall on one point of the plateau. The main role of the menisci is to protect the joint from too much stress.

The second function of the meniscus - ensuring joint stability - is achieved as follows. They seem to wedge the joint due to their wedge-shaped shape.

Geometrically, the menisci resemble a crescent shape and have different thicknesses. So, in its central part the menisci are thinner than at the edges. With this shape, the menisci seem to form a depression - this makes the joint very stable. The ability of the menisci to change their shape due to elasticity makes the load distribution optimal during movement - the joint does not lose its stability even during dynamics.

So, ligaments and menisci perform the most important tasks of ensuring joint mobility, their stable state when walking and at rest, and proper distribution of the load on the bones, protecting them and removing friction. If you compare the knee joint with others, its structure turns out to be fundamentally special - unique. No other joint in the body has such a structure. For example, elbow joint is much simpler.

The muscles of the knee joint are represented by two groups - extensor muscles and flexor muscles. Their name speaks eloquently for itself.

The extensor muscles are located in front of the femur. Thanks to these muscles, a person can walk - when these muscles contract, the knee joint straightens. The so-called quadriceps muscle is the main one, as it extends the leg at the knee. The flexors - the muscles that bend the knee - are attached to the back of the femur and play an important role in the functioning of the joint.

Nerves are responsible for transmitting commands to contract certain muscle groups. The largest nerve in the structure of the knee joint is the so-called popliteal nerve - it is located at the back, as if under the knee. Damaged nerves, for example due to injury, are a reason to immediately consult a doctor for treatment.

Further, the popliteal nerve itself branches, forming the peroneal and tibial nerves. The latter goes to the back of the lower leg. The peroneal nerve is located at the upper end of the fibula and ends on the front of the lower leg.

Other Important Items

The circulatory system of the knee joint is formed by the vessels passing through it, which branch at the back of the joint in the same way as the popliteal nerve. There are only two main vessels here - an artery and a vein. It is customary to add the prefix popliteal to the names of these vessels. The artery supplies the knee joint with enriched blood, and the popliteal vein returns waste blood back.

When considering the structure of the knee, one cannot ignore the synovial bursae - this is an important and rather complex part of the knee joint. In medicine, such bags are often called bursae. Some diseases of the knee joints get their name from them, for example, bursitis - these are inflammations of the synovial bursae, which are quite difficult to treat.

The task of the synovial bursae is to ensure the gliding of tendons during contraction of the muscles associated with them. The bursae are filled with a fluid called synovial fluid, which serves as a lubricant for the tendons. The cavity of some bags is connected to the articular cavity.

There are a total of 6 bursae in the knee joint. They all have very interesting names: suprapatellar, deep infrapatellar, subcutaneous prepatellar, bursa of the semimembranosus, bursa of the semimembranosus and popliteal.

All the elements considered - ligaments, bones, tendons, menisci, vessels, muscles, nerves and bursae - are a single scheme that is considered as a whole - after all, all elements are interconnected. Many elements of the knee are fragile and require careful handling. Take care of your knees - avoid unnecessary overload.