How do amputated fingers grow back in some cases?

If a child loses a piece of one of his or her fingers, it is very likely to grow back, including bones and nails. The fingerprints, however, will be lost. Still, it is a very curious phenomenon, even for science.

Recent studies, published on the Nature portal, reported on the analysis made from these types of cases in mice and found that the same cuticle that is close to the nails also plays an important role in the formation of new fingers.

Cases

New York University doctor Christopher Allan says that in children, amputated fingers simply grow back without any procedure. Dr. Allan explained that he had been closely following a few years ago with the case of a little girl who lost her middle finger tips to his brother's bicycle spokes. The child's parents even took a fingertip to the hospital, waiting for it to be sewn.

Unfortunately, Dr. Allan was unable to "stick" the fingertip and chose to wait for the small limb to grow back. He said that the girl returned to her office after a few weeks, with the old fingertip in a plastic and the new, which grew alone on the tip of the mangled limb. According to him, the result was better than any surgical procedure.

This type of case in children has been reported since the 1970s by doctors around the world. But this only happens if the fingers are cut below the cuticle. If the child loses this structure too, the limb is unlikely to grow back.

Similarities

In the study cited earlier, scientists saw similarities in the process in mice. But in the case of these animals, even the oldest had the ability to have their toes regenerated, according to research leader Mayumi Ito. However, for this to happen, the amputated organ must at least have a bit of fingernail.

To find out the reason for this need, Mayumi and her team did stem cell research. The explanation is that nails, like hair, for example, grow all their lives. When a mouse has its amputated fingertip, the nail grows differently and forms a new type of claw. During this growth, bone structures and nerves are also stimulated to grow, and then the new little finger forms.

These stem cell studies have also found that this type of material can be used in various cases of limb regeneration and formation. Mayumi explained that she intends to test these cells on other more serious types of amputations to see if they have the same results, but first of all she wants to find that same type of cell in humans. Perhaps the ability to regenerate limbs is literally at our fingertips.