Bones of the lower limb of man. Joints of the lower limbs of man

Everybody can imagine a skeletonman, thanks to the numerous photographs and drawings that each of us saw in school. But do we know that the skeleton of an adult person consists of a large number of different bones, each of which performs a specific function?

The human skeleton: what is it made of?

The skeleton of a person is his support. It is not only able to act for the human body as a repository for its internal organs and systems, but is also a place of attachment of its muscles.

При помощи скелета человек способен совершать various movements: walk, jump, sit, lie down and more. An interesting fact is that the human skeleton - the connection of bones - is formed in a child who is still in the womb. True, at first it is only cartilage tissue, replaced in the process of his life on the bone. In a baby, the bones have practically no hollow space inside. It occurs there in the process of human growth. One of the most important functions of the human skeleton is the formation of new blood cells, which are produced by the bone marrow, which is located in it. The peculiarity of the bones of the human skeleton is the preservation during a lifetime (and therefore continuous growth and development) of a certain form. The list of human skeletal bones includes more than 200 items. Many of them are doubles, the rest does not form pairs (33-34 pieces). These are some of the bones of the sternum and skull, as well as the tailbone, the sacrum, the vertebrae.

Human limb functions

It is very important to know that the process of evolution, that is, the continuous development of man, left a direct imprint on the functioning of many of his bones.

The upper section of the human skeleton with its movinglimbs designed primarily for human survival in the world. With his hands, he is able to cook, do homework, serve himself, etc. Also, there are bones of the human lower limbs. Their anatomy is so well thought out that a person is able to be held upright. At the same time, they serve as the basis for movement and support. It should be noted that the lower limbs are less mobile compared to the upper ones. They are by weight and density more massive. But along with this, their functions are very important for a person.

Human skeleton

Consider the human skeleton:the skeleton of the lower limb and upper limb is represented by the belt and the free part. In the upper section, these are the bones: the chest girdle, the shoulder blades and the clavicle, the humerus and the bones of the forearm, the hand. Human bones of the lower limb include: the pelvic girdle (or paired pelvic bones), the thigh, the shin, and the foot. The bones of the free lower limb of a person, as well as the belts, are capable of supporting the weight of a person, therefore, they are so important for him. After all, in fact, only with the help of these connections can it be in a vertical position.

Pelvic girdle (paired pelvic bones)

The first component, which is the basis, forming the bones of the belt of the human lower limb, will be the pelvic bone.

It is she who changes her structure after sex.maturation of any adult person. Until this age, it is said that the pelvic girdle consists of three separate bones (ileum, pubic and sciatic), interconnected by cartilage tissue. Thus, they form a kind of depression where the head of the thigh is placed. The bone pelvis is formed by joining the anterior bones of the same name. Behind it is articulated by means of the sacrum. As a result, the pelvic bones form a kind of ring, which is a repository for human internal organs.

Femur and Patella

The bones of the belt of the lower limb of a person are notas mobile as the rest of it, which is called so - free lower limb. It consists of: thigh, shin and foot. The thigh, or femur, is a tubular bone. It is also the largest and longest of all the bones with which the human body is endowed. In its upper part, the femur connects to the pelvic girdle with the help of the head and a long thin neck. Where the cervix passes into the main part of the femur, there are two large bumps on it. It is here that the bulk of the muscles of the human lower limbs is attached. Down the femur becomes thicker. Here are two elevations, through which the thigh is connected, as a result, with the patella and the shin. The patella is a flat bone of a rounded shape, with which the knee is bent. The bones of the lower limb of a person, namely the thigh and patella, carry the following functions: the place of attachment of the bulk of the muscles located on the legs, and the possibility of bending the leg.

Shin

The human shin consists of two bones: tibial and fibula. They are located next to each other.

Первая из них достаточно массивная и толстая.From above, it connects to the outgrowths (condyles) of the femur and the head of the fibula. To the bottom, the tibial bone is transformed on one side into the medial ankle, and on the other, it is located directly under the skin. The fibula is smaller in size. But at the edges it is also thickened. Due to this, it connects from above to the tibia, and from below forms the lateral ankle. It is important that both components of the lower leg, which are also the bones of the human lower limb, are tubular bones.

Human foot bones

Human foot bones are divided into three mainparts: bones of the tarsus, metatarsus and phalanges of the fingers. It is important to note that the foot is the free bones of a person's lower limb. The first ones include seven bones, the main ones being the bone, called the ram and forming the ankle, and the heel bone. The bones of the metatarsus are further located. There are only five of them, the first one is much thicker and shorter than the others. The toes of the foot are made up of bones called phalanges. The peculiarity of their structure is that the big toe contains 2 phalanges, the other fingers - three pieces each.

Anatomy of the joints of the human lower limbs. Sacroiliac joint, pubic symphysis

Just want to say that all the joints of the lower limbs are very large, compared with the joints of the upper limbs.

They have a large number of different ligaments,thanks to which the variety of movements that can be done with the help of human legs. The bones and joints of the bones of the lower limb were originally created in order to support and move the human body. Therefore, of course, they are reliable, strong and able to withstand heavy loads. Let's start with the top, by location, joints. With their help, the pelvic bones are connected, and a pelvis is formed in humans. In front of such a joint is called the pubic symphysis, and behind - the sacroiliac. The first one is created on the basis of the pubic bones located towards each other. Strengthening the pubic symphysis is formed by a large number of ligaments. The sacroiliac joint is very strong and practically immobile. It is tightly fastened not only with the pelvic bones, but also with the lower spine with the help of dense ligaments.

Human pelvis: large and small. Hip joint

It has already been described above that the bones of the belt belowhuman limbs are represented primarily by the pelvic bones. They, connecting with the sacrum and pubic symphysis, form a pelvis. It is, figuratively speaking, a ring that protects all organs, vessels and nerve endings inside from external influences. Distinguished large and small pelvis. In women, it is much wider and lower than in men. The fair sex is thought out to facilitate the generic process, so the pelvis has a more rounded shape and a large capacity.

The joints of the lower limb bones are alsorepresented by one of the most prominent representatives of this group - the hip joint. Why is he so famous? Dislocation of the hip joint is the most known defect in the development of the lower extremities, which can be identified literally one month after the birth of a baby. It is very important to do it in time, as this untreated diagnosis can bring a lot of trouble in adulthood. The hip joint consists of the cavity of the pelvic bone and the head of the femur. The investigated joint has many ligaments, due to which it is strong and quite mobile. Usually experienced orthopedists can diagnose a hip joint developmental anomaly in children with a routine examination of the patient. Leaning the legs to the side in a supine position at 180 degrees is possible only with healthy hip joints.

Knee-joint

Imagine a human skeleton.The connection of bones in the form of joints is necessary for a person for the strength of the connection of bones and the creation of maximum mobility of all his limbs. An excellent example of such a connection is the knee joint. He, by the way, is considered the largest joint in the human body. And its structure is very complex: a knee joint is formed with the help of condyles, patella, tibial condyles. The entire joint is shrouded in reliable ligaments, which, along with ensuring the movement of the leg, keep it in the desired position. Thanks to him, not only standing, but also walking. The knee joint can produce various movements: circular, flexor and extensor.

Ankle joint

This joint serves to directly connect the foot and lower leg. Around there are numerous ligaments that provide a variety of movements and the necessary stability of the human body.

Plusphalangeal joints

The joints under study are interesting in their shape, according tocompared with other joints of the human lower limb. They look like a ball. Strengthening for them are bundles on the sides and on the sole of the foot. They can move, although the diversity of their movement does not differ: small leads to the sides, flexion and extension. Human foot consists of numerous (sedentary) joints and ligaments. With their help, and the movement is carried out, while the human body has the necessary support. So, we can conclude that the bones of the belt of the lower limb of a person are less mobile than the free bones of the same section. But the functions of this no less than those of none.

How do limbs develop with age?

We all know that during life certainThe human skeleton also undergoes transformations. The skeleton of the lower limb undergoes strong changes with age. The bones that develop on the basis of connective tissue have three stages of their change: connective tissue, cartilage and bone tissue.

Pelvic bone: it is laid during fetal development. Formed cartilaginous layers between the pelvic bones are usually preserved until human puberty. Next, they stiffen. Patella: ossification points may appear in a child byAt 2 years old, it completely happens around 7 years old. Interestingly, lower limbs in newborns grow much faster than in adults. The peak of such a rapid growth falls on the period of puberty: for girls - 13-14 years; boys - 12-13 years.

Remember that the human skeleton is subject to differentinjuries in the form of injuries and even fractures. Since he is entrusted with the implementation of such a large number of important functions of the body, it must be protected. Eating right (food with sufficient calcium content helps strengthen the skeleton), lead an active lifestyle (physical education and sports), monitor your health (any disruption in the functioning of the skeleton to check with a competent specialist) - all this needs to be done by everyone. And then you will meet your old age vigorous, healthy and cheerful.