Many have noticed that after the cast, more hair grows on the arm or leg than on the healthy side. For a long time, it was thought to be due to friction. In the sense that rubbing the plaster against the skin makes the hair grow.
It didn’t quite fit with traditional ideas about hair growth and loss. Friction usually causes hair to fall out. On the ankles of people, the hair is worn out by the elastic of the socks and then may not germinate for years.
In general, there is a whole range of different reasons for hair growth.
Sometimes excess hair grows over tattoos, sometimes along the edge of burns, sometimes at the sites of sclerotherapy of varicose veins, after surgery or against the background of psoriasis.
There was a case when a two-year-old girl was bitten by mosquitoes and itched a lot. Then, at the site of the bites, there were such two-centimeter blisters, from which hair grew in bundles. Like a mole. After six months, everything went away.
They say that this with the child came from an itch. Combing such sores is harmful.
A similar situation happens with mentally abnormal people who scratch their hands from scratch. Hair grows from these combs too.
Hypertrichosis
In general, such hair growth is referred to as hypertrichosis. That is, it grows vellus hair, and they do not depend on hormones.
Hair can grow on any part of the body.
What's wrong
It was not always possible to associate the plaster with the growth of excess hair. Well, or rather, there was a plaster of Paris, but it acted incomprehensibly.
Chinese traumatologists published the story of a fifteen-year-old boy who fell and broke his wrist. Over time, he also had hair branches under the plaster, but it grew not just under the plaster, but just above the place where the metal knitting needle was in the bone.
The piece of iron was far enough from the skin and it didn't look like it was scraping something from the inside.
Traumatologists agreed that it is not so much a mechanical irritation of the skin as an increase in the blood supply to the diseased part of the body.
Where there was a metal needle, the body of the Chinese boy triggered inflammation and poured more blood into it through the arteries.
It is clear that in this area the excess blood flow delivered many different tasty and useful for the healing of the fracture. Most likely the vellus hair follicles also receive some of this yummy and decide to grow a little longer than originally planned.
Well, that is, there are several phases in the life of a hair. The most important phase is called anagen. At this time, the hair is actively growing. Then something happens, the hair stops growing and falls asleep. Hair should fall out shortly after growth stops.
It seems that if additional portions of blood with all sorts of tasty treats are delivered to the hair, the hair follicles will not be able to refuse of such a gift, they forget about all the deadlines set by nature, and how children who have gone out on a New Year's Eve continue to eat sweets and grow. Nobody puts them to bed.
Well, from a fracture, from itching, from something else in the arms or legs, blood circulation increases, and the hair cannot deny itself the pleasure of growing a little more.
Usually such a holiday lasts several months. Then the hair will thin out.
Have you shaved one arm or leg for yourself?
