When talking about the knee, most people mean. Indeed, it is an important anatomical part, however, its functionality is impossible without muscles and tendons. When walking, running, playing sports, this area has a significant load, which increases the risk of damage. Let us consider in more detail the ligaments, the muscular apparatus and the problems that arise during the action of a traumatic factor.
Anatomy features
Three bones take part in the formation of the joint: part of the femur, patella and part of the tibia. The patella is represented by the femoral-tibial and femoral-patellar joints. Anatomical features contribute to the simultaneous mutual movement of bones in several planes.
The menisci, represented by cartilage from connective tissue, are the "pads" between the heads of the bones. Their function is to provide shock absorption, distribution of pressure and load during movement. On both sides, the menisci are connected to the joint capsule with the help of coronary ligaments.
Joint stabilizers are the following muscle groups, awareness of which is considered an important point in traumatization:
- The quadriceps muscle occupies the anterior surface of the thigh. It is considered the strongest anatomical structure of the muscular apparatus of this area.
- The sartorius muscle is the longest. It provides flexion of both the thigh and lower leg, bypassing around the knee joint.
- A thin muscle runs behind and slightly to the side of the joint, allowing hip adduction and knee flexion.
- The large adductor muscle is involved not only in adduction of the thigh, but also in its extension or extension of the pelvis in relation to the thigh.
- Behind the transverse axis passes a two-headed one, which allows you to bend the lower leg, unbend the thigh, and provide outward movement.
- Behind and inside the joint, the tendon muscle passes, which extends the thigh, flexes the lower leg and provides circular rotation of the limb.
- performs functions similar to those of the dryer.
- The triceps muscle of the lower leg flexes the lower leg at the knee and the foot at
- Short and flat is located on the back surface. The function is to flex and rotate the lower leg.
Functions of the knee
The performance of the knee joint is important for the human body. It can move along the vertical and frontal axes. Extension and flexion occurs along the frontal axis, along the vertical - rotation of the limb.
Flexion of the joint allows the human leg to take a step forward without hitting the limb on the ground, but gently placing it. Otherwise, the human leg would be extended in the upper front direction by raising the hip.
Ligament apparatus
The knee joint, whose ligaments are represented by five main groups, is considered to be an anatomically complex part of the body. Its composition includes the following types of ligaments:
- collateral (tibial, peroneal);
- cruciform (front, back);
- transverse ligament of the knee;
- posterior (arcuate, popliteal, patellar ligament, medial and lateral);
- coronary (menisco-femoral, menisco-tibial).
In case of trauma, especially sports injuries, the main load occurs on the cruciate ligaments of the knee joint. The terms of recovery and the rehabilitation period depend on the nature of the injury and the damaging factor, the characteristics of the victim's body, last from 4 to 6 months.
Cruciate ligaments and their functionality
The anterior ligament runs from the posterior superior part of the meniscus of the femur through the cavity of the knee joint, attaching to the tibia, which is included in the articular conglomerate. Its function is to stabilize the knee joint by limiting forward movement of the lower leg.
The posterior ligament continues from the anterior part of the bony prominence of the femur and, crossing the joint cavity, is attached to the tibia in the back. The ligament does not allow excessive displacement of the lower leg back.
Cruciate ligament injury
Such injuries are considered the most complex and dangerous, requiring full treatment. Incorrectly selected or untimely started therapy leads to the development of lameness and persistent limitation of functioning. Most often, such injuries occur in professional athletes when skiing, skating, jumping, wrestling, arising from a strong blow or an unsuccessful turn, fall.
Severe piercing pain and a characteristic click, a sharp limitation of mobility may indicate that the ligament of the knee joint is torn. The victim cannot move independently, only relying on someone.
Injury to the posterior ligament occurs with a strong overextension of the knee or during a blow to the anterior surface of the lower leg. Damage to the anterior cruciate ligament of the knee joint is the most common. The symptoms of this injury are included in the "Thurner's triad" along with a torn meniscus and an external ligament.
Clinical picture
The knee joint, the ligaments of which have a partial tear, becomes hyperemic, swollen, painful to the touch and when trying to move. Blood accumulates in the joint cavity (hemarthrosis). You should not confuse the knee joint, which has a similar clinic, with the symptoms of an injury that occurred a few days ago.
A complete rupture of the cruciate ligaments causes excessive mobility of the lower leg in the anteroposterior plane. Checking such a symptom is carried out by two specialists at the same time. The first holds the back of the thigh and bends the painless limb at the knee at a right angle. The second doctor checks the movement of the lower leg forward and backward. When stretched or torn, such a sign will be negative.
Sprain means a slight tear of the fibers, accompanied by moderate soreness, slight swelling, and the absence of hemorrhage. Restriction of motor function occurs to an insignificant extent.
Diagnostics
Determining the mechanism of injury allows you to find out possible damage to the anatomical structures. Before examining an injured knee, the doctor examines a healthy one to find out the structural features. The state of internal structures is assessed using ultrasound and MRI.
Differential diagnosis allows to exclude fractures of bones, patella, meniscus rupture. With a dislocation, the bones are displaced relative to each other, there is no possibility of motor function, there is a springy resistance when trying to passive movements. For damage to the ligaments, the complete absence of movement is not characteristic, it is limited due to the pain syndrome. There is also no spring resistance.
The fracture is accompanied by deformation, the appearance of crepitus and pathological mobility. However, there are fractures that do not have such signs. In this case, confirmation of the diagnosis requires x-ray examination, ultrasound or MRI.
Principles of treatment
In case of partial injuries (stretching, tearing), assistance is provided in the emergency room. The limb should be in an elevated position, the first few days - bed rest. The first day after the injury requires the application of cold to the damaged area. The joint is fixed with a tight elastic bandage, which allows you to maintain the physiological position of the limb during movement. It is impossible to leave a bandage at night, so that there is no circulatory disturbance. Pain relief requires the use of analgesics ("Ketanov", "Ketalong", "Nalbufin").
The knee joint, the ligaments of which require not only conservative therapy, but also surgical treatment, needs a long rehabilitation period. After all the same measures as with partial injuries, physiotherapeutic measures are used, including massage, physiotherapy exercises, electrophoresis with medications.
Quite often, surgery is required when there is a rupture of the cruciate ligament of the knee joint. The operation to restore the integrity of the anatomical structures is necessary for normal functioning. Surgical intervention is performed six months after injury to the joint.
The ideal candidate for implementation is considered to be a young athlete who needs to perform jerky movements with the limbs in his sport. Older people who do not have a lot of physical activity are more suitable for conservative therapy and the use of physiotherapy exercises.
An ACL plasty requires the use of a graft taken from the patellar ligament or hamstring (autograft). It is also possible to use synthetic prostheses, however, their use may be rejected by the patient's body.
Sewing in synthetic grafts is a common procedure when the knee joint is torn. Treatment with the help of surgical measures is considered the method of choice in such a case.
Surgical practice has shown that simple suturing of injured structures practically does not ensure the restoration of functionality.
What are the complications of a knee injury?
Common complications of knee injuries include:
- The development of arthritis is possible 2-3 weeks after joint damage. An inflammatory reaction occurs as a result of circulatory disorders and the entry of pathological microorganisms into the injury zone. It is characterized by pain syndrome, the appearance of swelling, hyperemia, limitation of mobility due to pain.
- The appearance of degenerative changes in the form of arthrosis is accompanied by the formation of osteophytes, thinning of cartilage tissues.
Forecast
After an injury, most of the victims are interested in: "Rupture of the ligaments of the knee joint, how long does it heal?" This question is considered in each clinical case individually. Depending on the nature of the injury and the characteristics of the body, full performance may return in six months, or maybe in a few months.
The mechanism of damage itself is important and how the victim received a rupture of the ligaments of the knee joint. How long the injury heals also depends on the exact observance of the advice of the treating specialist. Early initiation of therapy, taking the necessary medications and adherence to the regimen can speed up the healing process and prevent the development of complications.
Prevention
The list of preventive measures used to minimize joint damage is as follows:
- adequate physical activity;
- inflammation of the ligaments of the knee joint should be treated in a timely manner;
- balanced diet;
- refusal to abuse alcohol and tobacco;
- avoiding hypothermia;
- control of the minimum stay of limbs in static poses;
- the right choice of shoes, the rejection of high heels.
Injury to the knee joint can be prevented, which is one of the simpler measures than restoring its functionality due to damage.
The knee joint, its structure in humans, has a complex structure. It is designed to carry heavy loads. Nevertheless, the knee joint, the structure of which, it would seem, provides for everything, very often suffers from various diseases. Diseases of the knee joint are not easy to treat, they can be associated with long-term increased stress on it, due to a person's excess weight, knee injuries, metabolic disorders in the human body, lack of vitamins and trace elements.
The anatomy of the knee is designed to avoid friction between the bones, to soften the impact. 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 whole structure is formed;
- menisci - play an important role in providing joint mobility;
- nerve endings and a network of blood vessels: revitalize the knee, making it sensitive to various influences;
- ligaments and cartilage: are the connecting link between bones and muscles, taking on all the 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 occupies the first two places at once: in complexity and in size. The complexity of the joint structure makes the treatment of related diseases difficult.
The knee consists of three bones - the femur and tibia, or simply the tibia, the bones are covered from above by the patella, which protects the joint. The knee joint connects these bones and provides them with mobility, performing the main functions of the knee - flexion and extension.
The smooth cartilage provides a comfortable glide of one bone over another when bending the knee. This cartilage covers those parts of the bones that come into contact with each other. It is part of all three constituent bones - the femur, tibia and patella or patella.
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 are only between the two main bones - the tibia and femur.
A special sheath covers the entire joint from the outside. Its inner part is called the synovial bursa. This bag is filled with the so-called articular fluid. This fluid is used to lubricate the cartilage, further improving gliding and reducing stress and friction in the joint. But that's not all: synovial fluid has another purpose - it is a nutrient for cartilage, providing and maintaining its unique properties.
The anatomy of the knee joint also provides for the presence of ligaments. They are needed so that the bones are securely fixed relative to each other and fit snugly against the menisci. 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 - external and internal. In case of damage to the ligaments, their treatment is carried out with the help of 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 tibia or tibia is located below and receives the load from the femur. It is called the tibia, so as not to be confused with another tibia - the fibula, but it is not part of the joint, so we will call the tibia easier - the tibia. The third bone is the kneecap. This is a small bone with a slightly rounded shape - it can be compared to a triangle with very rounded corners. This bone is often referred to as the patella.
The femur has two protrusions resembling the shape of a ball. These protrusions are called the 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 - a plateau. The full name is the tibial plateau. It consists of two halves - almond and lateral plateau.
Integral parts of the joint are the patella and several synovial bags 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 device of the patella 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. In the event of a kneecap injury, immediate treatment is required.
The cartilage covering the surfaces of the adjacent parts of the bones has an average thickness of about 6 millimeters. Of course, in children this figure is less 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 the damping elements of the joint. In the knee, cartilage covers all three bones.
Ligaments are dense connective tissue. They are needed to connect the bones that form the joint to each other. The lateral ligaments are located on the side of the joint, and the so-called collateral ligaments also got their place there. In addition to general strengthening of the joint, these ligaments serve to prevent the 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. The cruciate ligaments also serve as limiters for the movement of bones in unnecessary directions. The anterior and posterior ligaments are also needed in order to prevent the main bones from moving relative to each other.
By providing control of the mobility of the bones within the joint, the cruciate ligaments of the knee joint perform a very important task.
The stability of the bones in the joint is also achieved with the help of other formations similar to ligaments. These formations, called menisci, are located between the femur and tibia in the places of their protrusions on both sides. In their structure, cartilage and meniscus, although similar in appearance, are very different in structure and perform different tasks.
Meniscal disease resulting from overload or injury is 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 of the bones, thereby reducing the load, that is, the pressure per unit area of the femur on the tibia;
- provide a stable state of the joint, helping the ligaments.
In case of loss of one of the functions of the meniscus, it is urgent to consult a doctor for treatment.
The menisci are flexible pads under the contact surfaces of the bones and behave as if a spherical surface rests on a flat surface covered with a pillow. In this case, the pillow to some extent repeats the roundness of a spherical surface - the meniscus behaves in a similar way.
Being such soft pads, the menisci also fill the voids that could form in the places where the bones fit, if there were no menisci. The space to be filled is located between the condyles and the tibial plateau.
Thus, the presence of menisci provides the best distribution of the weight of the human body on the tibia, distributing the load on the entire surface of the tibial plateau. Otherwise, if nature had not provided for the menisci in the design of the joint, the entire load would fall on one point of the plateau. The main role of the menisci is precisely to protect the joint from too much stress.
The second function of the menisci - ensuring the stability of the joint - is achieved as follows. They seem to wedged the joint due to their wedge-shaped shape.
Geometrically, the menisci resemble the shape of a crescent and have different thicknesses. So, in its central part, the menisci are thinner than along the edges. With this form, the menisci, as it were, form a cavity - this makes the joint very stable. The ability of the menisci to change their shape due to elasticity makes the distribution of the load optimal even during movement - the joint does not lose its stability even during dynamics.
So, the ligaments and menisci perform the most important tasks of ensuring the mobility of the joints, their stable state when walking and at rest, and the proper distribution of the load on the bones, protecting them and removing friction. If we compare the knee joint with others, then its device will be fundamentally special - unique. No other joint in the body has such a structure. For example, the elbow joint is much simpler.
The muscles of the knee joint are represented by two groups - the extensor muscles and the 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 - with the contraction of these muscles, the knee joint is straightened. The so-called quadriceps muscle is the main one, since it extends the leg at the knee. Flexors - knee-flexing muscles - are attached behind the femur and play an important role in the operation of the joint.
Nerves are responsible for transmitting commands to contract certain muscle groups. The largest in the structure of the knee joint is the so-called popliteal nerve - it is located behind, as if under the knee. Damaged nerves, for example as a result of injuries, are a reason to seek immediate medical attention for treatment.
Further, the popliteal nerve itself branches, forming small and tibial nerves. The latter goes to the back of the leg. The peroneal nerve is located at the upper end of the fibula and ends already at the front of the lower leg.
Other important elements
The circulatory system of the knee joint is formed by the vessels passing through it, which branch out at the back of the joint in the same way as the popliteal nerve. There are only two main vessels - 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 the waste blood back.
Considering the structure of the knee, one cannot ignore the synovial bags - this is an important and rather complex part of the knee joint. Such bags in medicine are often called bursae. Some diseases of the knee joints also take their name from them, for example, bursitis is an inflammation of the synovial bags, which are quite difficult to treat.
The task of the synovial bags is to ensure the sliding of the tendons during the contraction of the muscles associated with them. The bursae are filled with a fluid called synovial fluid, which is what lubricates the tendons. The cavity of some bags is connected to the articular cavity.
In total, there are 6 bursae in the knee joint. All of them have very interesting names: suprapatellar, deep subpatellar, subcutaneous prepatellar, semimembranosus muscle bursa, semimembranosus own bursa and popliteal.
All the considered elements - ligaments, bones, tendons, menisci, blood vessels, muscles, nerves and bursae - are a single scheme, which 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 overloads.
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.
Content:knee structure
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 causes of disability is injury to this particular joint.
It consists of the following formations:
- bones - femur, tibia and patella,
- nerve endings and blood vessels
- cruciate ligaments.
Functions
The knee joint in its structure is close to the hinge joints. This allows not only to bend and unbend the lower leg, but also to perform pronation (inward rotation) and supination (outward movement), turning the bones of the lower leg.
Also, when bending, the ligaments relax, and this makes it possible not only to turn the lower leg, but also to perform rotational and circular movements.
Bone components
The knee joint consists of the femur and tibia, these tubular bones are interconnected by a system of ligaments and muscles, in addition, in the upper part of the knee there is a rounded bone - the patella or patella.
The femur ends with two spherical formations - the femoral condyles and, together with the flat surface of the tibia, form a joint - the tibial plateau.
bones of the knee
The patella is attached to the main bones by ligaments, located in front of the patella. Its movements are provided by sliding along special grooves and femoral condyles - a pallofemoral deepening. All 3 surfaces are covered with a thick layer of cartilage, its thickness reaches 5-6 mm, which provides cushioning and reduces thorns when moving.
Connecting components
The main ligaments, together with the bones that make up the device of the knee joint, are cruciate. In addition to them, there are lateral collateral ligaments on the sides - medial and lateral. Inside are the most powerful connective tissue formations - 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, preventing the tibia from moving backward from the femur. Ligaments ensure the connection of the bones during movement and help to hold it, the rupture of the ligaments leads to the inability to make arbitrary movements and lean on the injured leg.
knee ligaments
In addition to the ligaments, there are two more connective tissue formations in the knee joint that separate the cartilaginous surfaces of the femur and tibia - the menisci, which are very important for its normal functioning.
Menisci are often referred to as cartilage, but are closer in structure to ligaments. The menisci are round plates of connective tissue located between the femur and the tibial plateau. They help to properly distribute the weight of the human 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 when considering 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.
photo of meniscus
Muscles of the knee
The muscles located around the joint and providing its work 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 - muscles adducting the thigh - thin and large adductor muscles.
knee joint muscles
- One of the most powerful muscles in the human body is the quadriceps. It is divided into 4 independent muscles, located on the anterior surface of the femur and attached to the kneecap. There, the tendon of the muscle turns into a ligament and connects to the tuberosity of the tibia. Intermediate muscle, one of the branches of the quadriceps muscle, in addition, joins the capsule of the knee and forms the muscle of the knee. 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 she goes around him from the inside and is attached to the tuberosity of the tibia. This muscle is bipartite and therefore participates in the flexion of both the thigh and lower leg, as well as in the movement of the lower leg inward and outward.
- Thin muscle - starts from the pubic joint, goes down and is attached to the knee joint. It helps adduct the hip and flex the leg.
In addition to these muscles, the tendons of the biceps femoris, tendon, semimembranosus and popliteal muscles pass through the knee joint. They provide adduction and abduction movements of the lower leg. The hamstring is located directly behind the knee and assists in flexion and inward rotation.
Innervation and blood supply of the knee
The knee joint is innervated by branches, which is divided into several parts and innervates the lower leg, foot and knee. Directly the knee joint is innervated by the popliteal nerve, it is located behind it, and is divided into the tibial and peroneal branches.
knee nerves
The tibial nerve is located on the back of the lower leg, and the peroneal nerve is in front. They provide sensory and motor innervation of the lower leg.
The blood supply to the knee joint is carried out with the help of the popliteal arteries and veins, whose course repeats the course of the nerve endings.
knee blood supply
What causes trauma
Depending on which of the components of the knee is damaged, there is a classification of injuries, diseases and pathologies. It can be:
- dislocations,
- fractures of the bones surrounding the joint,
- inflammatory and dystrophic diseases,
- damage to tissues inside and around the joint, that is, cartilage, capsules, ligaments, and adipose tissue.
The knee joint is one of the most complex structures in the human body. It is formed by the fusion of the surfaces of bones such as the femur, tibia and kneecap.
Inside the joint there is a meniscus: medial and lateral - which perform the function of shock absorption for the knee joint.
Since the knee joint has a large load, it is strengthened by a large number of ligaments. All ligaments are divided into external and intra-articular.
External ligaments of the knee joint:
- peroneal collateral ligament;
- tibial collateral ligament;
- oblique popliteal ligament;
- arcuate popliteal ligament;
- patellar ligament;
Patellar ligaments (medial and lateral patellar ligaments)
Intra-articular ligaments:
- anterior cruciate ligament;
- posterior cruciate ligament
External ligaments of the knee joint
fibular collateral ligament- is formed from the external epicondyle of the femur and follows the outer surface of the head of the fibula. It is not attached to the capsule.
Tibial collateral ligament- goes from the inner epicondyle to the inner surface of the tibia. Fusion with the joint capsule in front and behind. And on the inside it is firmly connected to the edge of the medial meniscus.
Functions collateral ligaments – hold the condyles of the femur and tibia together. Thus, protecting the knee joint from lateral bending from side to side and rotation.
Patellar ligament (patellar) - formed by the tendons of the quadriceps femoris. Fibrous strands of this ligament, going down, are attached to the upper edge of the patella and its anterior surface. And they end on the tuberosity of the tibial surface, which is located on the anterior surface of the bone.
Function- serves to suspend the cup, which is sent along the inner surface by cartilage for better glide of the condyles of the bone.
Medial (inner) and lateral (outer) patellar ligaments- also formed by the tendons of the quadriceps femoris. Partially, the bundles are directed to the patella, and partially to the tibia, its anterior surface, near the articular cartilage.
Function- serves to hang the cup, as in the previous bundle.
Oblique popliteal ligament- passes behind the joint capsule.
It is formed from the tendons of the semimembranosus muscle and begins at the medial-posterior edge of the internal condyle of the tibia. Then it follows up and out along the posterior surface of the capsule, where it ends, partly weaving into the joint capsule, and partly attached to the femur along the posterior surface.
Arcuate popliteal ligament- also located on the back of the knee joint.
It originates immediately from two bones of the head of the fibula, from the posterior surface, and from the external epicondyle of the femur. The place of attachment is the posterior surface of the tibia. From the point of attachment, they follow an arc, rise up, bend to the inside and, partially, attach to the oblique popliteal ligament.
Intra-articular ligaments of the knee joint
The cruciate ligaments are intra-articular and are covered by a synovial membrane and cross over each other.
Anterior cruciate ligament- Covered by synovial membrane. It starts from the outer edge of the bone protrusion of the femur, and attaching to the tibia, the anterior intercondylar field, passes through the joint cavity.
Functions- limits the movement of the femur forward in relation to the lower leg.
Posterior cruciate ligament- stretched between the medial condyle of the thigh and the posterior intercondylar field of the tibia, and also penetrates into the knee joint. It is also covered with a synovial membrane.
F functions- stabilizes the knee joint so that the thigh does not move back in relation to the lower leg.
By preventing movement back and forth, the cruciate ligaments hold the condyles of the femur in one place, as if rolling them on the condyles of the tibia. Without the cruciate ligaments, the hip will go backwards in flexion and forward in extension.
Each person tries in every possible way to protect himself from various diseases, Because health is the most important thing.
In order to avoid diseases, it is necessary, first of all, to know the characteristics of the body.
In the article we will consider the structure of the knee joint.
The knee joint belongs to the category of trochlear, so it has one axis of motion, which 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 in the body. It is formed by three bones: from above, the femur, from below, the tibia, and in front is the patella, 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 problems. The kneecap can easily shift to the side and move up or down. The upper part (the 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. Behind 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 - a kind of layer (cartilaginous pads), with the help of which the stability of the joint increases. In other words, these are knee shock absorbers. They are located between the tibia and the femur. When a person moves, the menisci of the knee joint change shape (compress).
The menisci are the shock absorbers of the knee.
Experts distinguish several types of meniscus of the knee joint:
- Lateral (sometimes called external). It is very mobile, while being injured less often than the second type;
- Medial (internal). The meniscus is inactive, associated with the collateral (internal) lateral ligament of the knee joint. This structure often causes a joint and collateral joint.
Capsule of the knee joint
The system includes the capsule of the knee joint. This is a kind of fibrous case, with the help of which the bones are in contact with each other. The shape of this capsule can be compared to an elongated cylinder, the back wall of which is concave inward.
The capsule of the knee joint is a kind of case
The articular capsule is attached to the tibia and to the 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 (a lubricant for cartilage) that makes sliding painless.
It also nourishes the cartilage with useful substances that slow down their wear.
From the upper and lower bones, protrusions are formed, 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 and femur, the patella (patella), which are in contact with each other, is covered with smooth cartilage. This makes sliding easy.
Knee bags
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 bags of the knee joint, thanks to which the muscles, tendons, fascia can move freely and painlessly.
Scientists have six main bags, which include:
- suprapatellar bag;
- Deep subpatellar bag;
- Subcutaneous prepatellar bag;
- bag of the semimembranosus muscle;
- Own bag of the semimembranosus muscle;
- Bag of the hamstring.
The structure of the ligaments of the knee joint
With ligament injuries, a person experiences discomfort, cannot move normally and exercise. The ligaments of the knee joint and their anatomy is a rather complex system.
It includes the following elements:
1. Anterior cruciate ligament of the knee joint.
- It begins on the internal 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 to stabilize the knee joint, controls the displacement of the lower leg.
The ligaments of the knee joint and their anatomy is a complex system.
3. Collateral (internal) lateral ligament of the knee joint.
- Experts distinguish three parts of this bundle:
- Upper (has the largest size in the system of external ligaments. It has an oval 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 inside of the meniscus).
The medial collateral ligament of the knee joint normalizes the movement of the lower leg.
4. External lateral ligament.
In the lower part, the lateral ligament of the knee joint is connected to the fibula. It starts from the external condyle. When the leg is extended, the ligament is tense, and when flexed, it is relaxed. It has no connection with the meniscus, because there is a fatty layer between them.
A little below the kneecap 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 exercise, while it is the ligaments that most often cause various injuries of 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 unbend the leg, turn it to the sides.
Also, the knee allows a person to do a lot of exercise and move around. In this case, the joint is the place that most often lends itself to damage. First of all, this is due precisely to the complex anatomy of the knee.
