How fast do nerves grow back

Motor nerves have a time limit for healing. If the motor endplate receives no nerve impulse for more than months, it dies away and there is no longer any way that the muscle can be activated by the nerve.

The muscle then whithers away. Thus surgical repair of motor nerves needs to happen within months of the injury. Before sensation returns to the injured area, your limb is at risk of damage as it has no protective sensation. Please be careful of your hands or feet, especially around hot or sharp objects. Similarly, before the motor nerves recover your hand or limb may not be able to move normally or may develop abnormal postures. Hand therapy or physiotherapy will allow movement to be maintained while the nerve cells regenerate.

As your nerve recovers, the area the nerve supplies may feel quite unpleasant and tingly. This may be accompanied by an electric shock sensation at the level of the growing nerve fibres; the location of this sensation should move as the nerve heals and grows. Over time, these feelings subside and the area should begin to feel more normal.

Unfortunately, nerves never recover completely after they have been cut. I use a microscope or magnifying glasses loupes to repair your cut nerve with sutures finer than a human hair. This type of nerve repair surgery has the best recovery rates. Whether or not I can perform direct nerve repair on your injured limb depends on the injury your nerve has suffered. Sometimes I cannot directly repair your nerve ends, for example, if there is a piece of nerve missing or a delay in repair.

With nerve grafting, I take a length of nerve from somewhere else in your body and place it as a graft. I perform this repair using a microscope, too. You will have a scar from the surgery and often a numb patch in the area I took the nerve graft from.

Possible donor nerves include sensory nerves of skin of the forearm and leg. Having a numb patch on the side of your arm or foot is usually less bother than having a numb area on your hand. Now researchers at the University of Pittsburgh have found an effective way to bridge such a gap—at least in mice and monkeys—by inserting a biodegradable tube that releases a protein called a growth factor for several months.

In a study published Wednesday in Science Translational Medicine , the team showed that the tube works as a guide for the nerve to grow along the proper path, and the naturally occurring protein induces the nerve to grow faster. More than half of injured soldiers suffer nerve injuries, she says. And as the daughter and granddaughter of military men, she considers it her mission to help their successors.

Car crashes and accidents involving machinery such as snowblowers can also damage nerves involved in hand, arm, leg and foot control. In the U. When the injuries are severe, the only current treatment is to take a nerve from somewhere else on the body, Marra says.

But patients recover just about 50 to 60 percent of function in the damaged nerve. The new device restored nearly 80 percent of function, the study showed. It uses glial-cell-derived neurotrophic factor GDNF , a protein that promotes nerve cell survival. And that recruits other cells to come in and repair the nerve. It is better to make advances with small steps, as the Pittsburgh researchers have, she says. Materials provided by University of South Carolina.

Original written by Bryan Gentry. Note: Content may be edited for style and length. Science News. Journal Reference : Pabitra K. Sahoo, Amar N. Current Biology , ; DOI: ScienceDaily, 15 October University of South Carolina. Trigger that leads to faster nerve healing.