– (Lauro Henriques Jr./)
1) When a bone breaks, the blood vessels inside it rupture, causing bleeding and the formation of a clot. The site becomes inflamed, but within 24 hours, the ends of the ruptured vessels are sealed, stopping the bleeding almost completely.
– (Lauro Henriques Jr./)
two) The fracture region is filled with pieces of broken bone and dead tissue, which are removed by the action of cells called osteoclasts. They phagocytose (“eat” and “digest”) these fragments. The process can take weeks, depending on the size of the lesion.
– (Lauro Henriques Jr./)
3) From the first hours after the injury, angioblasts, cells responsible for the formation of blood vessels, also come into action. They will give rise to new vessels within the bone and will repair others that have ruptured with the fracture.
– (Lauro Henriques Jr./)
4) At the same time, the bone marrow begins to regenerate. Composed basically of blood and fat, it is inside the medullary canal of the bone, which is filled with new cells.
– (Lauro Henriques Jr./)
5) Bone reconstitution itself takes place from two highly vascularized membranes: the periosteum and the endosteum. While the periosteum completely surrounds the bones, the endosteum is a thinner layer that lines them internally.
– (Lauro Henriques Jr./)
6) Both the periosteum and the endosteum have the capacity to produce cells called osteoblasts, which will give rise to bone tissue. One or two days after the fracture, osteoblasts begin to invade the interior and surface of the clot.
– (Lauro Henriques Jr./)
7) The deposition of osteoblasts at the fracture site leads to the formation of bone callus, which appears both externally and internally. Meanwhile, the clot is decreasing, as the cells that form it continue to be “devoured” by the osteoclasts.
– (Lauro Henriques Jr./)
8) Within two weeks, the callus, also formed by fibrous and cartilaginous tissue, manages to unite the ends of the fracture with the intact part of the bone. In six weeks, the fissure disappears.
– (Lauro Henriques Jr./)
9) The next phase, which can last for months, is consolidation, when bone calcification occurs. Calcium, which gives bones strength and reaches the site through the bloodstream, helps to repair the damage once and for all.
– (Lauro Henriques Jr./)
10) The final and longest stage of bone regeneration – it can take up to ten years – is remodeling. Osteoclasts strike again, «sanding» the surface of the bone to reduce the callus. In the end, the fracture area, which until then remained more susceptible to breakage, regains its former strength.
Curiosity: Bone is one of the few organs capable of regenerating on its own. But, of course, he doesn’t do magic. That’s why, most of the time, a little medical help is needed for them to stick in the correct position. That’s when good old plaster comes into play and, in more serious cases, metal pins.
Curiosity: Many people who have suffered a fracture complain of pain in the area when the weather cools down. This is because, in general, the elasticity of the area that broke and the rest of the bone is different. In temperature changes, there is stress in this region, which causes pain.