Charles,an active 8-year-old boy, was playing and sustained a 3 inch laceration of his mid forearmwhile climbing over a chain link fence trying to retrieve a ball. Mom cleaned and covered it, and brought him to our office.

 

It was a deep clean cutresembling one made with a scalpel. After numbing the area well, I cleaned it thoroughly and put in 7 sutures. When finished mom commented how good it looked. Because the cut was so clean and sharp, the edges came together leavingonly a fine thin suture line. He returned in 7 days to have the sutures removed.

 

It really healed nicely and mom said, “He will barely have a scar, it looks great!”

 

Six weeks later Mom brought him back and wanted to know if she should take him to a plastic surgeon. “I’m afraid the scar is becoming a keloid. It looked so good at first, but now it is raised and pink. We do form keloids in our family.” Sure enough, the suture line was pink and raised about a millimeter, but it looked healthy and was not infected. How do wounds heal?

 

When one injures himself and sustains a deep violation of the skin (laceration, burn or deep abrasion), the healing process goes through 4 distinct and predictable stages. These are hemostatic, inflammation, pro-liberation and maturation/remodeling.

 

Hemostasis:

 

Immediately after such an injury, the blood vessels constrict to restrict the loss of blood in the injured area. The platelets in the blood will begin a process of sticking together and forming threads of fibrin into a mesh to help plug the leaky blood vessels and start to form a clot.

 

Inflammation:

 

Over the next few days, there is swelling and edema from the leaky blood vessels and damaged tissue. There is an increase in the white blood cells to the area.These will aid in the removal of bacteria, dead and damaged cells and debris.

 

Proliferation:

 

This is the period of new tissue growth that involves various stages. First, there is “neo-vascularization” or angiogenesis whereby new blood vessels are formed to serve the healing area. Collagen begins to be laid down forming a new supporting matrix. The epidermis (outer layer of our skin) begins to form a new cover with new epidermal cells.This is called re-epithelialization. These steps are occurring simultaneously and overlap.The wound will now take the form of granulation tissue which is raised because of the collagen, and pink/red because if the new blood supply. Towards the end of this stage, the wounds will begin to contract as cells called myo-fibroblasts, which are like smooth muscle cells. They will contract bringing the edges of the healing wound closer together.

 

Maturation/Remodeling:

 

During the proliferation stage of healing, the collagen that is first laid down is type III collagen which is very dis-organized and bulky. As maturation proceeds, the type III collagen becomes type I collagen which is more orderly and properly aligned forming cross links which allow it to lie close together in a streamlined manner. This allows the “raised” scar to flatten out and thin out. During this final stage of healing, the “new” blood vessels that were so vital in the healing process are no longer needed. They undergo a process called apoptosis which is essentially a programmed cell death. They are destroyed. This causes the pink color of the scar to give way to the typical silvery color of a scar. The maturation stage of healing can last from a month to over a year.

 

The collagen of a healing wound will reach around 20% of its tensile strength by 3 weeks, and about 80% by 3 months. Once a wound is finally healed, it will have about 80% of its pre-injury strength.

 

Getting back to Charles, his wound was healing nicely and I re-assured mom that this was the normal process of healing.

 

She shouldn’t expect to see the “final product” for another few months. The raised pink scar was newly forming skin with a new blood supply. As such, this new skin was very susceptible to sunlight and would easily burn.She MUST be sure to use a good sunscreen to protect it.

 

Charles’ yearly physical came 6 months later. Since there was no mention of his scar I asked mom how it turned out. “Oh, I forgot about it. It turned out great…Charles show the doctor your arm.” Sure enough, he had a thin silver scar that was barely noticeable. I commended Charles for “doing his homework”as his laceration healed just as predicted.