Why itching is a sign of wound healing

After a person is injured, the wound may become itchy during the healing process. The doctor will say, "If the wound is itchy, it is not far from healing." Generally speaking, this is indeed the case, so people often regard itchy wounds as a sign that the wound is about to heal.

It's hard for people to describe what it feels like to itch. Despite rapid advances in medicine, itch remains poorly understood. The currently accepted view is that impulses from the skin are collected by nerve fibers in the spinal cord and higher nerve centers and then transmitted to the cerebral cortex for analysis. If the sensory information transmitted by the nerves is incomplete or unclear, this is the feeling of itch. It is generally believed that the itch conduction pathway happens to be the pain conduction pathway. Therefore, it can explain that when the skin is itchy, the pain caused by scratching replaces the itch and plays a role in relieving the itching. This is what people often say "either pain or itching".

When a person is injured, the skin and subcutaneous tissue are the first to be damaged, and the nerves and blood vessels therein are also damaged at the same time. The damaged tissue cells release various inflammatory mediators, which stimulate the peripheral nerves, so the wound will cause pain and bleeding. After an injury, various tissues need to speed up their growth to replace the damaged parts, but their growth rates are different. Connective tissue grows the fastest, followed by epithelial tissue, and nervous tissue grows the slowest. When the wound is almost healed, nerve endings grow into the new connective tissue and skin. Moreover, the newly developed nerve endings are not yet fully mature and are very sensitive. They produce impulses when slightly stimulated, but the information formed is incomplete or unclear, which leads to the feeling of itching. After the wound has healed completely, the nerve endings gradually develop and adapt to the new environment, and the sensory information they transmit gradually becomes more complete, so you no longer feel itchy.