The foot is divided into tarsus, metatarsus and toe bones.

Tarsus

Tarsus, tarsus, formed by seven short spongy bones, ossa tarsi, which, like the bones of the wrist, are located in two rows. The posterior, or proximal, row is made up of two relatively large bones: the talus and the underlying calcaneus.

The anterior, or distal, row consists of medial and lateral sections. The medial section is formed by the scaphoid and three sphenoid bones. In the lateral section there is only one cuboid bone.

Due to the vertical position of the human body, the foot bears the weight of the entire overlying section, which leads to a special structure of the tarsal bones in humans compared to animals.

Thus, the calcaneus, located in one of the main supporting points of the foot, acquired in humans the largest size, strength and elongated shape, elongated in the anteroposterior direction and thickened at the posterior end in the form of a heel tubercle, tuber calcanei.

The talus has adapted for articulations with the bones of the lower leg (above) and with the scaphoid bone (in front), which determines its large size and shape and the presence of articular surfaces on it. The remaining bones of the tarsus, also experiencing great burden, became relatively massive and adapted to the arched shape of the foot.

1. Astragalus, talus, consists of a body corpus tali, which in front continues into a narrowed neck, collum tali, ending in an oval convex head, caput tali, with an articular surface for articulation with the scaphoid bone, facies articularis navicularis.

The body of the talus on its upper side bears the so-called trochlea, trochlea tali, for articulation with the bones of the lower leg. The upper articular surface of the block, facies superior, the point of articulation with the distal articular surface of the tibia, is convex from anterior to posterior and slightly concave in the frontal direction.

Lying on both sides of its two lateral articular surfaces of the block, facies malleolares medialis et lateralis, are the point of articulation with the ankles.

Articular surface for the lateral malleolus, facies malleolaris lateralis, bends below onto the lateral process extending from the body of the talus, processus lateralis tali.

Behind the trochlea, a posterior process, processus posterior tali, departs from the body of the talus, separated by a groove for the passage of the tendon m. flexor hallucis longus.

On the underside of the talus there are two (anterior and posterior) articular surfaces for articulation with the calcaneus. There is a deep, rough furrow between them. sulcus tali.

Anatomy of the talus in the picture

2. Heel bone, calcaneus. On the upper side of the bone there are articular surfaces corresponding to the lower articular surfaces of the talus. A process of the calcaneus, called sustentaculum tali, talus support. This name is given to the process because it supports the head of the talus.

The articular facets located in the anterior part of the calcaneus are separated from the posterior articular surface of this bone by a groove, sulcus calcanei, which, adjacent to the same groove of the talus, forms a bone canal with it, sinus tarsi, opening on the lateral side on the dorsum of the foot. On the lateral surface of the calcaneus there is a groove for the tendon of the peroneus longus muscle.

On the distal side of the calcaneus, facing the second row of tarsal bones, there is a saddle-shaped articular surface for articulation with cuboid bone, facies articularis cuboidea.

Posteriorly, the body of the calcaneus ends in the form rough bump, tuber calcanei, which forms two tubercles towards the sole - processus lateralis and processus medialis tuberis calcanei.

Anatomy of the calcaneus in the picture

3. Scaphoid bone, os naviculare, located between the head of the talus and the three sphenoid bones. On its proximal side it has an oval concave articular surface for the head of the talus. The distal surface is divided into three smooth facets that articulate with the three sphenoid bones. On the medial side and downwards, a rough tubercle protrudes from the bone, tuberositas ossis navicularis, which can be easily felt through the skin. On the lateral side there is often a small articular platform for the cuboid bone.

4, 5, 6. Three sphenoid bones, ossa cuneiformia, are called so by their external appearance and are designated as os cuneiforme mediale, intermedium et laterale. Of all the bones, the medial bone is the largest, the intermediate bone is the smallest, and the lateral bone is medium in size. On the corresponding surfaces of the sphenoid bones there are articular facets for articulation with neighboring bones.

Free part of the lower limb Bones of the foot

Talus

rice. 195. Astragalus, talus, right. A - bottom view; B - rear view.

Talus , talus (see fig.) is the only bone of the foot that articulates with the bones of the lower leg. Its posterior section - body of the talus, corpus tali. Anteriorly, the body passes into a narrowed section of the bone - neck of the talus, collum tali; the latter connects the body with the forward direction head of the talus, caput tali. The talus bone is covered from above and on the sides in the form of a fork by the bones of the lower leg. The ankle joint, articulatio talocruralis, is formed between the bones of the tibia and the talus. Accordingly, the articular surfaces are: upper surface of the talus, facies superior ossis tali, having the shape of a block - trochlea tali, and lateral, lateral And medial, ankle surfaces, facies malleolaris lateralis et facies malleolaris medialis. The upper surface of the block is convex in the sagittal direction and concave in the transverse direction.

The lateral and medial ankle surfaces are flat. Lateral malleolar surface extends to superior surface lateral process of the talus, processus lateralis tali. The posterior surface of the body of the talus crosses from top to bottom groove of the tendon of the long flexor of the big toe sulcus tendinis m. flexoris hallucis longi. The groove divides the posterior edge of the bone into two tubercles: the larger medial tubercle, tuberculum mediale, and smaller lateral tubercle, tuberculum laterale. Both tubercles, separated by a groove, form the posterior process of the talus, processus posterior tali. The lateral tubercle of the posterior process of the talus sometimes, in the case of its independent ossification, is a separate triangular bone, os trigonum.

On the lower surface of the body in the posterolateral region there is a concave posterior calcaneal articular surface, facies articularis calcanea posterior. The anteromedial sections of this surface are limited by the surface that runs from back to front and laterally groove of the talus, sulcus tali. Anterior and outward from this groove is located middle calcaneal articular surface, facies articularis calcanea media. Does not lie in front of anterior calcaneal articular surface, facies articularis calcanea anterior.

Through the articular surfaces, the lower part of the talus articulates with the calcaneus. The anterior part of the head of the talus has a spherical shape scaphoid articular surface, facies articularis navicularis, through which it articulates with

1

2 anterior talar articular surface

See also in other dictionaries:

Talus- (talus) The talus, talus, is the only bone of the collum tali; the latter connects the body with the forward-facing foot, which articulates with the bones of the lower leg. Its posterior section is the head of the talus, caput tali. The talus bone on top is called... Atlas of Human Anatomy

Talus- Astragal (shown syn... Wikipedia

Foot bones- in the area of ​​the tarsus, tarsus, are represented by the following bones: talus, calcaneus, navicular, three wedge-shaped bones: medial, intermediate and lateral, and cuboid. The metatarsus, metatarsus, includes 5 metatarsal bones. Phalanxes...... Atlas of Human Anatomy

Skeleton of the free part of the lower limb- (pars libera membrae inferioris) consists of the femur, patella, leg bones and foot bones. The femur (os femoris) (Fig. 55, 56), as well as the humerus, ulna and radius, is a long tubular bone, the proximal epiphysis ... ... Atlas of Human Anatomy

Bones of the lower limb - … Atlas of Human Anatomy

Knee-joint- Three bones take part in the formation of the knee joint, articutatio genus: the distal epiphysis of the femur, the proximal epiphysis of the tibia and the patella. The articular surface of the femoral condyles is ellipsoidal, curvature... ... Atlas of Human Anatomy

Ankle joint- The ankle joint, articulatio talocruralis, is formed by the articular surfaces of the distal epiphyses of the tibia and fibula and the articular surface of the trochlea of ​​the talus. On the tibia, the articular surface is represented by... ... Atlas of Human Anatomy

Includes seven spongy bones arranged in two rows. The proximal (posterior) row consists of two large bones: the talus and calcaneus; the remaining five tarsal bones form the distal (anterior) row.

Talus has a body, a head and a narrow part connecting them - a neck. The body of the talus is the largest part of the bone. Its upper part is a block of the talus with three articular surfaces. The upper surface is designed to articulate with the lower articular surface of the tibia.

Two other articular surfaces lying on the sides of the trochlea: the medial malleolar surface and the lateral malleolar surface articulate with the corresponding articular surfaces of the ankles of the tibia and fibula. The lateral malleolar surface is much larger than the medial one and reaches the lateral process of the talus.

Behind the trochlea, the posterior process of the talus extends from the body of the talus. The groove of the flexor hallucis longus tendon divides this process into a medial tubercle and a lateral tubercle. On the underside of the talus there are three articular surfaces for articulation with the calcaneus: the anterior calcaneal articular surface; the middle calcaneal articular surface and the posterior calcaneal articular surface. Between the middle and posterior articular surfaces there is a groove of the talus. The head of the talus is directed anteriorly and medially. To articulate it with the scaphoid bone, the rounded scaphoid articular surface is used.

Calcaneus- the largest bone of the foot. It is located under the talus bone and protrudes significantly from under it. At the back, the body of the calcaneus has a downwardly inclined tubercle of the calcaneus. On the upper side of the body of the calcaneus, three articular surfaces are distinguished: the anterior talar articular surface, the middle talar articular surface, and the posterior talar articular surface. These articular surfaces correspond to the calcaneal articular surfaces of the talus. Between the middle and posterior articular surfaces a groove of the calcaneus is visible, which, together with the corresponding groove on the talus, forms the sinus of the tarsus, the entrance to which is on the dorsum of the foot on the lateral side.

A short and thick process extends from the anterior superior edge of the calcaneus on the medial side - talus support. On the lateral surface of the calcaneus there is a groove for the tendon of the peroneus longus muscle. At the distal (anterior) end of the calcaneus, there is a cuboid articular surface for articulation with the cuboid bone.

Scaphoid located medially, between the talus and the three sphenoid bones. With its proximal concave surface it articulates with the head of the talus. The distal surface of the scaphoid is larger than the proximal one; it has three articular platforms for connection with the sphenoid bones. At the medial edge, the tuberosity of the scaphoid bone (the attachment site of the tibialis posterior muscle) is noticeable. The lateral aspect of the scaphoid may have an inconstant articular surface for articulation with the cuboid.

Sphenoid bones(medial, intermediate and lateral), located anterior to the navicular bone and located in the medial part of the foot. Of all the bones, the medial cuneiform bone is the largest, articulates with the base of the 1st metatarsal bone; intermediate sphenoid bone - with 2 metatarsal bone; lateral sphenoid bone - with 3rd metatarsal bone.

Cuboid located on the lateral side of the foot between the heel bone and the last two metatarsal bones. At the junction of these bones there are articular surfaces. In addition, on the medial side of the cuboid bone there is an articular platform for the lateral sphenoid bone, and somewhat posteriorly and smaller in size for articulation with the scaphoid bone. On the lower (plantar) side there is a tuberosity of the cuboid bone, in front of which there is a groove for the tendon of the peroneus longus muscle.

The ankle joint of the human leg is a complex structure and functional load of bones, a large number of ligaments and muscles. The talus (os talus) is a kind of bone shock absorber that separates the foot and lower leg. Densely surrounded by muscles and ligaments, the largest meniscus of the human bone skeleton does not have a single muscle attachment. Its interesting shape, unusual structure, and location allow it to withstand and distribute enormous loads to other elements of the foot.

Important! Our ancestors adapted the talus bones of domestic ungulates for the popular game of “knocks” because, falling onto a plane, they always find themselves in a stable position. The expression “rolling the dice” is still used in board games and even in the gambling business.

The complex anatomical structure of the human ankle, consisting of a system of bones, muscles and tendons, allows you to rely when moving (running, walking, jumping) not on the entire plane of the foot, but on several of its key supporting areas, which makes possible comfortable, fast movement with high-quality shock absorption.

The skeletal structure of the foot is an intricate system of more massive tarsal bones, smaller metatarsal bones and thin phalangeal bones of the toes. Where is the talus bone located? It enters the tarsal section. This is the second largest bone of the ankle, “hidden” in its very middle, securely connected to the fibula and tibia, the navicular and calcaneal bones of the foot, as well as to a whole system of tendons and ligaments.

Functionality and anatomy

The complexity of this bone and its multiple connections with the rest of the foot and lower leg determine its importance and versatility.

Functional purpose

The role of the ram is to distribute the weight of the human body and additional loads that arise during movement on the foot, simultaneously in different directions. One direction is to the heel, through the posterior subtalar joint located below, and the second is to the arch of the foot forward and inward, through the talonavicular joint; the third - to the arch of the foot forward, outside, through the anterior talocalcaneal joint.

Uniform distribution of compression, multidirectional load, good shock absorption give the foot the following necessary for upright walking:

• sustainability;
• stability combined with great mobility;
• optimal balance between the possibility of active movement of large amplitude and reliability of support.

Anatomical structure

The talus, entangled with ligaments and tendons, surrounded by the articular surfaces of other adjacent joints, is distinguished by an asymmetrical complex structure.

Anatomy of the talus

The bony articular meniscus of the ankle consists of:

• head, slightly flattened in front;
• body, with a large articular plane at the top (trochlear), and on the sides - with medial and lateral planes;
• neck, completely covered with cartilage;
• posterior process.

The bony head is attached to the scaphoid bone through the scaphoid plane. The body of the ram is wrapped around the ankle bones of the lower leg. There are two tubercles on the process (lateral, medial).

Important! In some people, most often ballet dancers, a triangular bone formation is formed that replaces the lateral tubercle. It is possible that it is formed due to high regular loads in jumping parts of ballet performances.

The cartilage covering the articular planes of the talus is the largest relative to the rest of the bones of the human body. The wide part of the ram located in front gives a confident, stable position to the ankle. The articular plane below ensures tight contact with the calcaneal tubercle. The talus is also called the supracalcaneal bone because the calcaneus, located under it, provides support for it.

Ligamentous and articular joints directly associated with bone

The spherical shape of the talus-calcaneal navicular joint includes: the talus bone head, the sphere of the anterior and superior calcaneus, and the navicular bone. The relationship between the movements of the subtalar joint and the talocalcaneal navicular joint is determined by the axis of rotation, which is common for both joints. It passes through the bony head, the calcaneal tubercle. The movement goes around this axis, its angle is approximately 55 degrees. In addition to being axially centered, the talocalcaneal navicular joint is integrated with the subtalar interosseous ligament.

The supracalcaneal bone has no muscle attachments, but is tightly surrounded by them and the tendons that connect the lower leg to the foot.

The blood supply to the ram is provided by a system of ligaments and several blood branches directly from nearby arteries. If the blood supply is impaired, for example, with cervical fractures, especially with a dislocation, serious consequences can occur: aseptic necrosis, formation of a cervical false joint.

Possible types of injuries, consequences, treatment

The risk group includes motorcyclists, football players, skiers, and jumpers from great heights. Ligaments and joints are more often injured. A fracture of the bone meniscus of the ankle occurs only with strong mechanical impact: road accidents, falls on straight legs. A fracture of the posterior process of the talus is possible with intense sharp flexion movements. This injury is called a snowboarder's fracture, as it is typical for fans of this sport.

Fractures, treatment

According to statistics, only 5% of ankle fractures are associated with injury to the talus. Usually severe bruises, fractures of other bones, and damage to ligaments occur. Individual injuries are rare and are classified according to the location of the fracture:

• necks – 50%;
• heads (in practice, not found in an isolated version);
• bodies – 13-23%;
• shoots – 10-11%.

Signs of a fracture:

• swollen bent foot, its deformation, clubfoot;
• severe pain in movements in the ankle;
• sharp pain when moving the big toe;
• severe pain on palpation.

Finally, the presence of a fracture is best determined by examination using an x-ray. X-rays are performed in various projections. In difficult cases, an MRI is performed.

Any injury to the talus is intra-articular due to the cartilage with which it is almost completely covered. With such an injury, the leg will be very painful, its position will be forced, and quick anatomical stable fixation will be required within 24 hours.

The choice of treatment method depends on the type of injury and is finally selected by the doctor after carrying out the necessary diagnostic measures.

For closed fractures without displacement or with minor displacement, conservative treatment is used with plaster immobilization of the ankle for 8-12 weeks. In difficult cases, with displacements of bone fragments, surgical treatment is practiced with combining and fixing the broken elements with screws and knitting needles.

Fractures of the supracalcaneal bone are classified as severe injuries, often accompanied by complications - arthrosis (subtalar, tibiotalar), avascular necrosis.

Necrosis, treatment

If the blood supplying vessels that saturate the bone head are damaged or they are compressed for a long time, the quality blood supply to the bone is disrupted and, as a complication, necrosis is possible. Aseptic necrosis (avascular) can lead to complete limitation of ankle mobility and disability.

Osteonecrosis cannot be detected quickly during an x-ray examination; only the already developed second or third stage of the disease will be visible on x-rays. Timely MRI and computed tomography will help identify degenerative processes.

Treatment can be conservative (with the help of medications that slow down the course of the disease), or surgical. In advanced cases of osteonecrosis, removal of the affected bone is inevitable.

The success of treatment depends on the timely detection of the disease; if you do not endure pain and seek medical help in a timely manner, the functioning of the joint can be restored without surgery.