A man's bone is so strong that it is a miracle that it can be broken! Bones can carry load 30 times larger than a brick. The strongest bone in the human body is the lower jaw.
It can withstand a load of about 1,600 kg!
How does a fractured bone heal itself?

Nevertheless, the bone sometimes breaks due to an action of a strong force.
Each bone fracture has a name, depending on how the bone is broken. If it has bounced only on one part of its surface, so that its ends are still connected, then it is a wrinkled or incomplete fracture. If the bone is completely split into two parts, it is a simple or plain fracture. When the bone is broken into more than two parts, it is a complicated fracture. Finally, if the bone parts break through the muscles and the skin so that the broken bone extends through the skin, it is called open fracture.

Adjusting the parts of broken bones is like sticking pieces of a broken bowl. The pieces of the broken bones must be arranged one at a time to touch each other. But the doctor does not use any kind of glue. The bone connective tissue cells multiply and connect the broken bones.
Bone tissue has a great ability to self-propagate. In a bone fracture, its parts and soft tissue, muscles, and blood vessels, around the fractures are torn and injured. One part of the injured tissue is extinct. The entire surrounding of the fracture, which contains bony pharynx and soft tissue, is soaked with clotted blood and lymph.
Just a few moments after the fracture, the young connective tissue cells are beginning to appear in that coiled mass. This is the first step in healing the fracture. These cells quickly multiply and soon after they accumulate calcium. During 72 to 96 hours after the fracture, they produce tissue that connects the bones.

In newborn tissue, more calcium is deposited than usual. Calcium helps to re-create the hard bone, which gradually develops over a period of months into normal bone. When the limb is broken, a gypsum bend is usually placed, preventing the bones from moving and the fractured parts are connected.