Skeleton of human shin. Small and large shin bone

What are the functions of the tibia and tibia? Where is each of them? How are they connected?

The first (tibia) bone is medial.

The severity of the whole body is transferred to the area of the support along the vertical (mechanical) axis of the entire leg. The tibia connects to the hip bone through the knee joint. The axis of the lower limb vertically passes through the center of the knee joint to the center of the ankle joint. The tibia of the foot bears the weight of the whole body, which causes it to be large (in comparison with the small one) in thickness.

Sometimes there is a deviation in the lateral or medial side, which entails a change in the angle between the shin and thigh. With strongly pronounced deviations, an "x-shaped" or "o-shaped" shape of the legs is observed.

The epiphysis (proximal margin) forms two (lateral and medial) condyle. On the side facing the thigh, they have weakly concave articular surfaces that perform a connective function. Separation of the articular surfaces of the condyles is accomplished by an elevation with two tubercles. At the anterior and posterior end of the elevation there is one small pit. The surfaces of the joints are surrounded by a thickened edge (a trace from the attachment of the joint capsule). The anterior surface of the bone has a very massive, rough convexity - the attachment of the tendon (in the form of the knee ligament) of the quadriceps muscle. The lateral part of the lateral condyle includes a small flat surface (the attachment site of the peroneal bone head). The body consists of the anterior, medial and lateral facets, between which are the posterior, medial and lateral surfaces. In this case, the sharpest (front) face and the medial surface are clearly probed through the skin. On the medial side of the lower distal end (epiphysis) there is a strong process (medial malleolus), behind which is a flat groove. In the lateral end of the distal margin is a notch where the small and large tibia connects. Adapters for abutting the skeleton of the foot are at the bottom edge.

The second (small, thin and long, with thickened ends), the tibia is located laterally in the lower leg. The proximal (upper) epiphysis forms the head. Through the flat roundish surface of the joint, it adjoins the lateral tibial bone condyle. The tip of the head is a protrusion, located somewhat laterally and posteriorly of this surface. The triangular shape of the body of the bone is somewhat twisted along the entire longitudinal axis. The distal (lower) epiphysis has a thickening and forms the lateral (with a smooth surface of the joint) ankle.

Fractures of condyles (intraarticular injuries) of the tibia.

As a rule, they arise when the shins deviate inward or outward or at the moment of falling onto the straight legs. There is a fracture of the inner and outer condyle. Intra-articular lesions may be accompanied by damage to the ligamentous apparatus in the knee joint, meniscus, intercondylar elevation, peroneal bone head, etc.

Fractures are accompanied by an increase in the volume of the joint, with the limb slightly bent. There is a deviation of the tibia to the outside (with damage to the external condyle) or inside (with damage to the internal condyle). In the condylar region, the transverse dimension is significantly enlarged. There is also a lack of active movements in the joint, including the inability to raise the leg in a straightened state. At passive movements there is a sharp pain. In some cases, damage to the external condyle is accompanied by damage to the cervix or peroneal bone head. In this case, damage to the nerve can be observed, which is indicated by a violation of the sensitivity and motor function of the foot.