The calcaneus bone (lat. Os calcis) is the mandibular sesamoid bone in humans. Its lower end articulates with the sole of the foot, its upper end with the talus; this joint springs somewhat with each step.
In an adult male, the upper end of the bone is unbuckled across, while the lower end, on the contrary, is thickened and expanded. In this case, the middle part is interplanar. The lower surface of the sphenoid is adjacent to the bone in front, the talus bone is inside, and the interosseous membrane of the foot is on the sides. Behind the bone, the cuboid bone tightly closes with its lower edge. In both medial and lateral sections there are protrusions on the bone: behind and on the sides - articular facets, in front - a tubercle. It has the shape of a protrusion and is equal to a semicircle, and the cutout is shaped like an arc. This print is surrounded by a neck. The width of the bone is approximately 2 cm. The front surface is smooth, in the posterior section it has two folds that divide it into three protrusions, and at the back there are three depressions. The surface of the neck is slightly rough. Its structure is elastic and contains a strong fiber system that allows for good springing. Bone fractures occur as a result of strong impact during childbirth or careless walking on a child’s foot. Such damage to bone tissue often causes pathological changes in the thumb area. You can also often find a post-traumatic pathological fracture that occurs as a result of impaired blood supply. This kind of damage occurs in the most common form in athletes from excessive stress.