A wound is a cut or opening in the skin. It can be just a scratch or a cut that is as tiny as a paper cut. A large scrape, abrasion, or cut might happen because of a fall, accident, or trauma. A surgical cut made by a healthcare provider during a medical procedure is also a wound. Your body has a complex system to patch up skin wounds. Each stage is needed for proper wound healing. Wound healing takes a number of parts and steps that come together to repair the body.
1. Stages of wound healing
Your body heals a wound in four main stages.
The stages include:
- preventing too much blood loss
- defending and cleaning the area
- repairing and healing
Keeping the wound clean and covered can help your body repair the area.
Stage 1: Stop the bleeding (hemostasis)
When you get a cut, scratch, or other wound in your skin, it usually starts bleeding. The first stage of wound healing is to stop the bleeding. This is called hemostasis.
Blood begins to clot seconds to minutes after you get a wound. This is the good kind of blood clot that helps to prevent too much blood loss. Clotting also helps to close and heal the wound, making a scab.
Stage 2: Scabbing over (clotting)
Clotting and scabbing phase has three main steps:
Blood vessels around the wound narrow. This helps to stop the bleeding.
Platelets, which are the clotting cells in blood, clump together to make a “plug” in the wound.
Clotting or coagulation includes a protein called fibrin. It’s “blood glue” that makes a net to hold the platelet plug in place. Your wound now has a scab over it.
Inflammation, which involves cleaning and healing
Once your wound isn’t bleeding any more, the body can begin cleaning and healing it.
First, the blood vessels around the wound open a bit to allow more blood flow to it.
This might make the area look inflamed, or a little red and swollen. It might feel a bit warm too. Don’t worry. This means help has arrived.
Fresh blood brings more oxygen and nutrients to the wound — just the right balance to help it heal. White blood cells, called macrophages, arrive on the scene of the wound.
Macrophages help clean the wound by fighting any infection. They also send out chemical messengers called growth factors that help repair the area.
You might see clear fluid in or around the wound. This means white blood cells are at work defending and rebuilding.
Stage 3: Rebuilding (growth and proliferative)
Once the wound is clean and stable, your body can begin rebuilding the site. Oxygen-rich red blood cells come to the site to create new tissue. It’s like a construction site, except your body makes its own building materials.
Chemical signals in the body tell cells around the wound to make elastic tissues called collagen. This helps to repair the skin and tissues in the wound. Collagen is like a scaffold that other cells can be built on.
At this stage in healing, you might see a fresh, raised, red scar. The scar will slowly fade in color and look flatter.
Stage 4: Maturation (strengthening)
Even after your wound looks closed and repaired, it’s still healing. It might look pink and stretched or puckered. You may feel itching or tightness over the area. Your body continues to repair and strengthen the area.
2. How long does it take for a wound to heal?
How long it takes to heal a wound depends on how large or deep the cut is. It may take up to a few years to completely heal. An open wound may take longer to heal than a closed wound.
According to Johns Hopkins Medicine, after about 3 months, most wounds are repaired. The new skin and tissue is about 80 percent as strong as it was before it was injured, per the University of Rochester Medical Center.
A large or deep cut will heal faster if your healthcare provider sutures it. This helps to make the area your body has to rebuild smaller.
This is why surgical wounds typically heal faster than other kinds of wounds. Surgery cuts normally take 6 to 8 weeks to heal, according to St. Joseph’s Healthcare Hamilton.
Wounds may also heal faster or better if you keep them covered. According to the Cleveland Clinic, wounds need moisture to heal. A bandage also keeps the wound cleaner.
Some health conditions can cause very slow healing or stop wound healing. This can happen even if your cut is due to surgery or a medical procedure.