Hypertrophic scars occur when the body creates too much scar tissue after an injury or surgery. Often the scar will grow for several months and then stabilize. True keloid scars behave more like tumors and often continue to grow even years after the initial trauma to the skin.
Even people who are not prone to hypertrophic scars can get them. Certain areas are more prone to poor scarring (over joints, the chest), and factors like infection, poor nutrition, tissue damage, and smoking can affect scar quality as well.
Scar creams are non-invasive and can generally improve the appearance of most scars. They are best used right after an injury, but they can be used even years later. Creams that have silicone in them have more clinical evidence than
other treatments like vitamin E and Mederma, although Mederma does work
well for some patients.
If the scar cream is not enough, the choice of treatment depends on what is bothersome about the scar. Tenderness, itching, and a raised appearance can be treated by massaging the scar, wearing silicone compression strips, and by injecting a small amount of steroid (usually Kenalog) into the scar. Redness and other discoloration can be treated with a laser that targets those types of pigments.
One final option is to perform scar revision by cutting out the original scar. If the original scar was due to infection, significant trauma, or from other factors that are now under control, it will often heal better. Scar revision can also rearrange the direction of the scar or break up the scar with zig zags (called a Z plasty), which can make them less noticeable.