articular capsule. Capsule - joint shell: its structure and injuries

In each joint, the main elements and additional formations are distinguished.

To main The elements include the articular surfaces of the connecting bones, the articular capsule surrounding the ends of the bones, and the articular cavity inside the capsule.

1) Articular surfaces connecting bones are usually covered with hyaline cartilage (cartilago articularis), and, as a rule, correspond to each other. If on one bone the surface is convex (articular head), then on the other it is correspondingly concave (articular cavity). The articular cartilage is devoid of blood vessels and perichondrium. It consists of 75-80% water, and 20-25% of the mass is dry matter, about half of which is collagen combined with proteoglycans. The first gives cartilage strength, the second - elasticity. Articular cartilage protects the articular ends of the bones from mechanical stress, reducing pressure and evenly distributing it over the surface.

2 ) Articular capsule (capsula articularis) , surrounding the articular ends of the bones, firmly fuses with the periosteum and forms a closed articular cavity. The capsule consists of two layers: outer fibrous and inner synovial. The outer layer is represented by a thick, durable fibrous membrane formed by fibrous connective tissue, the collagen fibers of which are directed mainly longitudinally. The inner layer of the joint capsule is formed by a thin, smooth, shiny synovial membrane. The synovial membrane consists of flat and villous parts. The latter has many small outgrowths facing the joint cavity - synovial villi, very rich in blood vessels. The number of villi and folds of the synovial membrane is directly proportional to the degree of joint mobility. The cells of the inner synovial layer secrete a specific, viscous, transparent yellowish liquid - synovia.

3) Synovia (synovia) moisturizes the articular surfaces of bones, reduces friction between them and is a nutrient medium for articular cartilage. Synovia is similar in composition to blood plasma, but contains less protein and has a higher viscosity (viscosity in conventional units: synovia - 7, and blood plasma - 4.7). It contains 95% water, the rest is proteins (2.5%), carbohydrates (1.5%) and salts (0.8%). Its quantity depends on the functional load falling on the joint. Even in such large joints as the knee and hip, its amount does not exceed an average of 2-4 ml in humans.

4) Articular cavity (cavum articulare) is located inside the joint capsule and is filled with synovium. The shape of the articular cavity depends on the shape of the articulating surfaces, the presence of auxiliary devices and ligaments. A feature of the joint capsule is that the pressure in it is below atmospheric pressure.

JOINT

Basic elements Additional formations

1. Articular surfaces 1. Articular discs and menisci

connecting bones 2. Articular ligaments

2. Articular capsule 3. Articular lip

3. Articular cavity 4. Synovial bags and vaginas

To additional joint formations include:

1) articular discs and menisci (discus et meniscus articularis). They are made of fibrocartilage and are located in the joint cavity between the connecting bones. So, for example, the menisci are in the knee joint, and the disk is in the temporomandibular joint. They seem to smooth out the roughness of the articulating surfaces, make them congruent, and absorb shocks and shocks when moving.

2) articular bundles (ligamentum articularis). They are built from dense connective tissue and can be located both outside and inside the articular cavity. Articular ligaments strengthen the joint and limit the range of motion.

3) Articular lip (labium articularis) consists of cartilaginous tissue, is located in the form of a ring around the articular cavity and increases its size. Articular lip have shoulder and hip joints.

4) Auxiliary formations of the joints are also synovial bags (bursa synovialis) and synovial sheaths (vagina synovialis) – small cavities formed by the synovial membrane and filled with synovial fluid.

Axes and types of movement in the joints

Movements in the joints are made around three mutually perpendicular axes.

Around front axle Maybe:

BUT) bending (flexio) , i.e. decrease in the angle between the connecting bones;

B) extension (extensio) , i.e. an increase in the angle between the connecting bones.

Around sagittal axis Maybe:

BUT) abduction (abductio) , i.e. removal of a limb from the body;

B) cast (adductio) , i.e. approach of the limb to the body.

Around longitudinal axis possible rotation (rotatio):

BUT) pronation (pronatio), i.e. rotation inward;

B) supination (supinatio), i.e. outward rotation;

AT) circling (circumductio)

Phylo-ontogeny of skeletal bone joints

In cyclostomes and aquatic fish, the bones are connected by continuous connections (syndesmosis, synchondrosis, synostosis). Landing led to a change in the nature of movements, in connection with this, transitional forms (symphyses) and the most mobile joints, diarthroses, were formed. Therefore, in reptiles, birds and mammals, the joints are the dominant joint.

In accordance with this, in ontogenesis, all bone joints pass through two stages of development, resembling those in phylogeny, first continuous, then discontinuous (joints). Initially, at an early stage of fetal development, all bones are connected to each other continuously, and only later (at the 15th week of fetal development in cattle) in the places of formation of future joints, the mesenchyme, which forms layers between the bones, dissolves, a gap is formed filled with synovia. Along the edges of the connecting bones, an articular capsule is formed, which forms the articular cavity. By the time of birth, all types of bone connections are formed and the newborn is able to move. At a young age, articular cartilage is much thicker than at an old age, since in old age there is a thinning of the articular cartilage, a change in the composition of the synovium, and even ankylosis joint, i.e. bone fusion and loss of mobility.

Joint classification

Each joint has a certain shape, size, structure and moves around certain planes.

Depending on this, there are several classifications of joints: by structure, by the shape of the articular surfaces, by the nature of movement.

According to the structure, the following types of joints are distinguished:

1. Simple (art.simplex). The articular surfaces of two bones (shoulder and hip joints) take part in their formation.

2. Complex (art.composite). Three or more articular surfaces of bones (carpal, tarsal joints) take part in their formation.

3. Complex(art. complexa)c they will have additional cartilage in the form of a disc or meniscus (knee joint) in the joint cavity.

According to the shape of the articular surfaces:

1. Spherical joints ( art. spheroidea). They are characterized by the fact that the surface of one of the connecting bones has the shape of a ball, and the surface of the other is somewhat concave. A typical spherical joint is the shoulder.

2. Ellipsoid joints ( art. ellipsoidea). They have articular surfaces (both convex and concave) in the form of an ellipse. An example of such a joint is the occipito-atlantic joint.

3. Condylar joints (art. condylaris) have articular surfaces in the form of a condyle (knee joint).

4. Saddle joints (art. sellaris). It is characterized by the fact that their articular surfaces resemble part of the surface of the saddle. A typical saddle joint is the temporomandibular joint.

5. Cylindrical joints (art. trochoidea) have articular surfaces in the form of segments of a cylinder, and one of them is convex, the other is concave. An example of such a joint is the atlanto-axial joint.

6. Blocky joints (ginglimus) are characterized in such a way that the surface of one bone has a recess, and the surface of the other has a guide, corresponding to the recess, ledge. An example of block-shaped joints is the joints of the fingers.

7. Flat joints (art plana) characterized by the fact that the articular surfaces of the bones correspond well to each other. Mobility in them is small (sacral-iliac joint).

According to the nature of the movement,:

1. Multi-axle joints. In them, movement is possible along many axes (flexion-extension, adduction-abduction, supination-pronation). An example of these joints can be the shoulder, hip joints.

2. Biaxial joints. Movement is possible along two axes, i.e. possible flexion-extension, adduction-abduction. For example, the temporomandibular joint.

3. Single axis joints. Movement occurs around one axis, i.e. only flexion-extension is possible. For example, elbow, knee joints.

4. Axleless joints. They do not have an axis of rotation and only the sliding of bones in relation to each other is possible in them. An example of these joints would be the sacroiliac joint and the hyoid joints, where movement is extremely limited.

5. Combined joints. Involves two or more anatomically isolated joints that function together. For example, carpal and tarsal joints.

It is block-shaped, in which there are only two types of movements - flexion and extension. Eversion and inversion are carried out in the talocalcaneal joint, which is referred to as flat. The talocalcaneal joint is very strong due to a powerful ligamentous apparatus, and most pronation-supination injuries result in damage not to the subtalar, but to the ankle joint.

Ankle joint formed by the distal ends of the tibia and fibula, forming a fork into which the talus enters. Block talus wedge-shaped, wider anterior than posterior, and is part of the talus that articulates with the tibia and fibula.

With the back flexion wide front wedge fits firmly into the fork, as a result of which the joint becomes very stable; however, in plantar flexion, the narrow posterior part of the talus block enters the fork, allowing for considerable joint mobility. With this in mind, it's not hard to see why most ankle injuries occur when the foot is in plantar flexion.

To understand mechanism damage to this important joint, the doctor emergency care it is necessary to know well the anatomy of the main soft tissue structures surrounding it. For convenience, these structures can be divided into three layers that envelop the joint (each subsequent lies above the previous one), and then consider the damage that occurs in each of the layers.
First layer- a capsule containing the ligaments of the ankle joint; the second is the tendons passing over the joint to the foot; the third is fibrous bundles that hold the tendons at their point of attachment to the bones of the foot.

Articular capsule of the ankle joint

Capsule, surrounding the ankle joint, is divided into four parts (ligaments): anterior, posterior, lateral and medial. The capsule is weak in front and behind, but is strengthened by ligaments on the inside and outside. The anterior ligament is thin and connects the anterior surface of the tibia and the neck of the talus and is usually damaged by extensive tears of the lateral ligament.

The talus is wider in front

rear bundle shorter than the front and stretches from the posterior edge of the tibia to the posterior surface of the talus. The lateral ligament is subdivided into three main bundles, which are the most commonly damaged ligaments in the human body. Between the outer ankle and the neck of the talus, the anterior talofibular ligament is stretched, which, if the ankle joint is injured, suffers more often than others.

In dorsiflexion, the wide anterior part of the talus block enters the fork of the ankle joint, thereby preventing movements in it. With plantar flexion of the ankle joint, a narrow rear part of the block is located inside the fork, which allows significant inversion-eversion movements in the joint

Between outer ankle and the posterior tubercle of the talus (sometimes it is represented by a separate formation and is called the triangular bone) is the posterior talofibular ligament, and from the outer ankle to calcaneus stretches the calcaneal-fibular ligament. Proximal to the lateral group of ligaments, the fibula is connected to the tibia by a series of strong fibrous fibers, which together form the so-called tibiofibular syndesmosis. This syndesmosis consists of an interosseous membrane that connects the tibia and fibula along their entire length. At the bottom, the membrane is strengthened by two thickening fibrous bundles: the anterior inferior and posterior inferior tibiofibular ligaments.

The most important ligaments of the anterior and outer sides of the ankle joint and tibiofibular syndesmosis

medial ligament called the deltoid. It is a quadrangular structure, characterized in that it is the only one among the ligaments of the ankle joint that contains elastic tissue, which gives the ligament a certain degree of extensibility and thereby reduces the likelihood of rupture. The deltoid ligament consists of four bundles intertwined with each other and stretching from the medial malleolus to the scaphoid, talus and calcaneus. Two of its bundles go to the talus; one of them is called the anterior tibio-talar ligament, which is attached to the neck of the talus, the other is called the posterior tibio-talar ligament.

Deltoid ligament. The spring ligament connects the talar support of the calcaneus to the scaphoid

This bundle located deeper than all of the four structures. The part of the deltoid ligament that connects the medial malleolus to the calcaneus is called the tibiocalcaneal ligament. It attaches to the supporting structure of the talus.

The tendons that cross the ankle joint lie superficial to the capsule. Note the synovial tendon sheaths

Talus, supported by these ligaments, moves with the foot in true dorsiflexion or plantar flexion and together with the lower leg in pure inversion-eversion movements. An important ligament that is not part of the capsule, but is often damaged in injuries of the ankle joint and midfoot, is the spring ligament.

This ligament is stretched between the supporting structure talus and navicular bone and closes the gap between the calcaneus and navicular bones. Its function is to provide additional support to the head of the talus when loaded with body weight. It consists of dense fibrous tissue, the sections of which resemble articular cartilage.

Tendons are held in place by fibrous bundles.

Ankle tendons

Superficial capsules The ankle joint contains tendons, none of which are actually attached to the joint itself, but all pass over it, which is important when considering the associated injuries of this joint. These tendons are divided into two groups: the extensor and flexor tendons of the foot. The extensors run along the anterior surface of the ankle joint, and the flexors run posterior to the medial malleolus. The third group are the tendons of the muscles of the fibula, passing behind the outer ankle. These tendons are surrounded by synovial sheaths; some of them reach 8 cm in length.

Superficial tendons there are three divergent fibrous bundles that keep the tendons from displacement. These bundles are classified similarly to tendons. Accordingly, the retainers of the extensor, flexor and tendon muscles of the fibula are isolated. The extensor retinaculum is divided into upper and lower retinaculums. The flexor retinaculum consists of a single fibrous bundle running behind the medial malleolus. The peroneal retinaculum is divided into two - the upper and lower tendon retinaculums of the muscles of the fibula.

The articular bag is a capsule of connective tissue that connects the articular surfaces and the articulation cavity. Due to which a closed cavity is formed with its structural components and functions.

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Anatomical features

The anatomy of the joint bag (knee, shoulder, hip, elbow, ankle) is represented by two structural units - fibrous and synovial. Each of them has its own structural features and functions. The capsule in the joint surrounds all the components of the joint, protecting and connecting them.

fibrous bag

This part of the capsule consists of two types of fibers - collagen and elastic. They form the outer and inner layers of the shell. In the first, the fibers are located in the longitudinal direction, corresponding to the axis of movement in the joint. In the second layer, the fibers are in a circular order.

The fibrous capsule is attached to the bone units by weaving its bundles to the periosteum. From all sides, the bag is pierced by ligaments and tendons located around the muscle tissue. There are holes in the shell through which, in some cases, the protrusion of the synovial component occurs.

Synovial membrane

The synovial part also consists of the outer and inner layers. The first is called the subsynovial, and the second is the directly synovial part. The outer part has a loose structure of a huge amount of reticulo-endothelial cell elements, fat, nerve endings, lymph and blood vessels. The synovial layer has fine structure, consists of a chondroitin substance, there are practically no elements of cells.

The inner shell covers almost the entire surface inside the articulation cavity. The exception is cartilage. The synovium also covers the ligaments within the joint. Passing through the fibrous capsule, it forms inversions and synovial bags.

In the capsule of the knee and other joints there is a layer of villi on the synovial membrane from the inside. These are fine fibers. different lengths, there are also folds of synovia and fat. Both folds and villi are enriched with blood capillaries. The number of villi depends on the age of the person and the functional characteristics of a particular joint. Fat folds and fluid act as a shock absorber for the bone surfaces in the joint during movements and various loads.

Role and functions in the body

The fibrous component provides mechanical unity of the articular surfaces. It protects bones from damage, is a pain receptor and a biological defense during pathological changes in the articulation.
The synovial membranes of the knee and all other human joints are responsible for the production of fluid in the articulation cavity. They also provide the metabolism and nutrition of all components, the removal of waste products. And the fat folds in the shell dampen the movement of the bones.

Diseases of the bags of articulation

The most common disease of the capsule in the joint is its inflammation. The disease is called bursitis. The bag may also rupture due to a traumatic impact.

Bursitis

This is an inflammatory process in the joint bag, which is accompanied by the accumulation of an excessive amount of synovial fluid. The main causes of occurrence:

traumatic lesions of the joint;
arthritis, arthrosis;
gout;
autoimmune diseases when the capsule is damaged;
consequence of excessive physical activity when playing sports, or peculiarities of work;
infection.

shoulder inflammation

The capsules of the shoulder joint are most susceptible, which is often complicated inflammatory process in tendons and muscle tissue. Bursitis of the knee bag is of three types, depending on the location of the lesion. This happens due to anatomical features knee, in which there is more than one articular bag.

Types of bursitis in the knee joint:

Patellar - the suprapatellar bag of the knee, which is located above the calyx, becomes inflamed. Affected people who spend a lot of time on their knees (laying tiles), or as a result of injury;
Popliteal - inflammation of the infrapatellar capsule, which is located under the knee. It is a complication of sprain and capsule;
Baker's cyst - an inflamed capsule, which is located on the back of the inner surface of the knee.

Bursitis manifests itself in the form of pain, swelling, limited freedom of movement in the joints. The specificity of sensations depends on the location of the inflammation. With shoulder bursitis, it is difficult for a person to raise their arm up and put on clothes. With inflammation of the elbow joint, there is practically no discomfort, but there is severe swelling.

In the acute phase, there is also an increase in skin temperature and redness, there may be a burning sensation. The acute period develops within a couple of hours, it is difficult to move the joint, palpation is also accompanied by pain. Chronic form can occur with repeated exacerbations of bursitis, frequent traumatic lesions. Due to frequent acute periods, the shell of the bag becomes thinner, which aggravates the course of the disease.

One of the most common injuries is the rupture of the capsule shells. This can be triggered by severe trauma, as well as weak ligaments and tendons. The shoulder and knee joints are most susceptible to such injury. The first is the most shaky and unstable in the human body, so joints often suffer with sudden movements. And the knees are constantly subjected to heavy stress in daily movements and especially with an active lifestyle and sports.

The main signs of a rupture are deep pain inside the joint, sensations of clicks during movements. Treatment consists of taking non-steroidal anti-inflammatory drugs and physiotherapy. Procedures help to relax muscle tissue, improve blood circulation. Next, special gymnastics is performed to strengthen and normalize the elasticity of ligaments and tendons. In extreme cases, surgery is indicated.

Video "Treatment of bursitis in the knee joint"

In the video you will see in more detail about the symptoms and treatment of bursitis in the knee.

Panina Valentina Viktorovna

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I found out about you on the Internet - I urgently need an MRI.

And here I am after the performance. I really liked your employees. Thank you for your attention, kindness and accuracy.

May everything be as good in your soul as I am now, despite all the problems ...

Be!!! We are happy! Your Panina V.V.

I found out about you on the Internet - I urgently need an MRI.

And here I am after the performance. I really liked your employees. Thank you for your attention, kindness and accuracy.

May everything be as good in your soul as I am now, despite all the problems ...

Be!!! We are happy! Your Panina V.V.

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Today we propose to discuss the topic: "capsule knee joint". We tried to fully reveal the topic and present it in a convenient way. You can ask your questions after reading the article in the comments.

joint capsule is a fibrous sheath covering the distal end of the femur and the proximal end of the tibia. It holds these bones in contact and forms the non-osseous wall of the articular cavity. Its inner surface is covered with a synovial membrane.

The general shape of the capsule (Fig. 78) is easy to understand if we compare it with a cylinder with a concave back wall (shown by the arrow). This leads to the formation of a septum in the sagittal plane, which almost divides the articular cavity into the inner and outer halves. The relationship of the capsule to the cruciate ligaments will be discussed later. On the front surface of the cylinder there is a window for the patella. The upper end of the cylinder is attached to the femur, and the lower end to the tibia.

Attachment of the articular capsule to the tibia is relatively simple (Fig. 79): to the anterior, outer and inner edges of the articular surface 1 (green dotted line). Behind and medially, it passes into the attachment of the posterior cruciate ligament PI to the tibia. Behind and laterally - lines the edge of the external condyle posterior to the tibial spine and joins the tibial attachment of the posterior internal PI and anteroexternal AE cruciate ligaments. The capsule does not pass between the cruciate ligaments, the interligamentous space 2 between them is filled with their synovial lining, which can be considered as a thickening of the articular capsule in the intercondylar fossa.

Attachment of the joint capsule to the femur is somewhat more complex (Fig. 80-83).

“Lower limb. Functional Anatomy”
A.I. Kapanji

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.

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 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 joint injuries of the medial meniscus and collateral 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.
Inner side capsule is called the synovial membrane.

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 cartilage beneficial 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.

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.

With ligament injuries, a person experiences discomfort, cannot move and exercise normally. 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 surface of the condyle, which is located outside. The ligament crosses the knee joint, it is attached in its cavity (in the intercondylar fossa).
This link is one of the most important.

It helps to stabilize the state of the knee joint, controls the displacement of the lower leg, and helps to hold the lateral condyle.

The anterior cruciate ligament of the knee joint is one of the most important.

The joint capsule is a shell of the bone joint, which is formed from connective tissue. The capsule attaches to nearby bones as they are close to the articular surface. As a rule, the periosteum grows together with the bag of the joint. So this design creates a cavity of the articular connection, which is closed and is quite tight. The capsule forms two layers: outer and inner. The capsule in the joint is also called the bag.

The articular bag (capsule) is stretched between the articulating bones and is attached along the edges of the articular surfaces

Capsule of connecting the bones of the musculoskeletal system: its structure and structure

The outer layer is called the fibrous membrane, the inner layer is called the synovial membrane. The outer layer, performing an additional protective function, is thicker and more durable than the inner one. It is formed from dense and elastic connective tissue fibers that have a longitudinal direction. In some cases, the capsule in the joint has additional auxiliary ligaments that strengthen it.

The inner layer, formed from the synovial membrane, is responsible for the production of a special substance. This fluid is secreted from the villi of the membrane. The substance is called synovial fluid. Due to it, friction in the bone joint is eliminated, it moisturizes and nourishes it.

It is the inner layer that is braided with a large number of nerve endings, therefore pain come from this center. Pain susceptibility occurs only due to these nerve endings. The structure of the capsule includes a large number of blood vessels that end at the ends of the villi (fibers, processes) of the synovial sphere. The bursa contains fibers from the ligaments. It is connected to the tendons of nearby muscles, which allows the limbs to move.

The capsule in the joint, surrounding the bone joint itself, protects it from damage (for example, ruptures).

The capsule consists of both dense and coarse fibers, as well as elastic compounds and loose tissues. Loose tissues take on the role of a filter, which perform both mechanical actions, and analyzer functions, and signaling.

The main types of bone joints of the human body

The articular connection not only connects the bones to each other, it is one of the important elements of the strengthening apparatus. In addition, the bone joint can move and rotate along three axes that are perpendicular to each other. Bone junctions include several closely spaced surfaces of bones. Articular joints are conditionally divided into simple (two-osseous), complex, complex and combined.

Bone articulation can move and rotate between multiple axes

Bone articular surfaces are of different configurations. They can be spherical, elliptical, cylindrical, flat or block-shaped. The most simple bone connections, for example, the interphalangeal joint thumb, can hold together two surfaces of different bones. Complex bones such as elbow joint, have such a structure that they can hold together several surfaces that belong to different bones. The combination of two simple bone joints is called a combined joint. At the same time, they are combined into a single mechanism, for example, the temporomandibular joint.

Complex articular joints, along with complex ones, can connect several bone surfaces, but the difference is that a special layer will be inserted between these surfaces, which looks like a line (meniscus) or has the shape of a disk. This layer divides the area into two cavities. They are independent. In the articular joint there are internal ligaments that will not allow the bone to change its position during movement.

Ligaments in the joint capsule perform the following functions:

hold the bones and prevent them from moving;
direct the movement of the bony joint (lateral ligaments) along one plane, which is a thickening in the articular joint.