What to know about scar tissue
Scar tissue is a collection of cells and collagen that covers the site of the injury. People can develop scar tissue on their skin as the result of an injury, surgery, or acne. Other areas of the body can also develop scar tissue, such as the heart muscle after a heart attack.
Scar tissue can present in a variety of ways, including:
A keloid is a raised, red-skin colored plaque of scar tissue that can form on tissues after an injury. Keloids often appear on the upper chest, shoulders, and upper back.
A hypertrophic scar is a more common form of scar tissue. People with hypertrophic scars may notice that they fade over time.
A contracture scar usually occurs in tissues that have had a burn injury. These scars can impair the movement of the affected area.
Causes and prevention
A keloid is a type of raised scar tissue.
Although doctors remain unsure of what causes scar tissue to form, they do know that hypertrophic scars and keloids can result from burns, insect bites, acne, chicken pox, piercings, tattoos, and surgery.
Researchers have also found that keloids develop more often in people with darker skin.
Both keloids and hypertrophic scars tend to occur more frequently in younger people between 10 and 30 years old.
The most important guideline for scarring is prevention. People who have risk factors for developing abnormal scars should avoid elective surgery when possible and treat conditions that can result in scarring, such as acne.
Sometimes, surgery is necessary.
People may experience itchiness and pain at the location of the scar. Other scars can restrict movements. Some people may experience emotional and psychological distress from the appearance of scars.
Doctors can prescribe treatments to reduce the appearance of scarring, but they must also address the psychological impact and physical restrictions a scar can cause.
Researchers estimate that scar treatments in the United States cost over $20 billion every year.
There is a variety of treatments available for scars, but they may not all be successful for everyone. It is important that doctors explain the limited effectiveness of these treatments and set reasonable expectations for people managing their scars.
Treatment options include:
- laser therapy
Onion extract may have anti-inflammatory properties and the ability to kill bacteria.
People usually tolerate onion extract well, but researchers have not found consistent evidence that this treatment is effective. One study found that it was no better than a petroleum-based ointment, such as Vaseline.
Mitomycin C is a type of chemotherapy agent that has limited effectiveness for treating keloids. Most studies have investigated the efficacy of topical mitomycin C when used alongside other treatments, such as radiation therapy and surgical removal of the keloid.
Researchers do not suggest mitomycin C for scar management because there is not enough reliable evidence to support its use.
Imiquimod is available in a 5% cream formulation. Some doctors prescribe imiquimod cream to people with keloids after surgical removal. Once again, this topical treatment has not shown consistent results in clinical trials for treating and preventing keloid scar formation.
Some doctors might inject bleomycin into the scar to stop the production of collagen at the site of the injury. Only a few studies have tested the effect of injectable bleomycin on improving the appearance of hypertrophic scars and keloids.
Some researchers have found that bleomycin may also reduce redness, itchiness, and pain associated with these scars.
Bleomycin is a treatment that doctors use in cancer treatments. It is a toxic substance, but doctors rarely report toxic side effects from injecting it into a scar.
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Interferon also affects the production of collagen, and doctors can inject it into injured tissue. Researchers have found in clinical studies that injecting interferon decreased the size of a keloid by 50% in 9 days. This produces a more significant effect than injecting a corticosteroid.
Another study showed that after injecting interferon into a hypertrophic scar, the quality and volume of the scar improved.
Doctors do not typically use interferon because it is expensive, and current evidence is not strong enough to support its use. It also requires three injections per week, which may be inconvenient for some people.
Corticosteroid injections are a common treatment option for keloid and hypertrophic scars.
Doctors prefer corticosteroid injections as the first choice for treating keloids and second choice of treatment for hypertrophic scars. Doctors use triamcinolone acetonide, which is an injectable corticosteroid.
The recommended dosing schedule may vary, but a typical injection schedule involves three to four injections every 3 to 4 weeks. Some people may require more than four injections. Researchers have demonstrated that between 50% and 100% of people responded to the treatment.
Some doctors will administer triamcinolone acetonide injections along with cryotherapy to improve a scar's thickness and decrease itchiness.
Botulinum toxin A
Some doctors have been injecting botulinum toxin A to prevent and treat scars for several years, but researchers have found inconsistent evidence for its effectiveness in scar management.
Cryotherapy involves using liquid nitrogen to cool body tissue to below zero temperatures. This seems to have an effect on scar management. This treatment may have a benefit in improving the appearance of scars by affecting the underlying scar tissue.
Some studies have reported a reduction of 51% of the volume of a scar following one treatment, but some experts think cryotherapy is more effective when used in combination with other treatments, such as injectable corticosteroids.
Doctors may use radiotherapy along with other scar treatments. Typically, people will receive radiotherapy after having a keloid removed to reduce the formation of another keloid.
Radiation can help to reduce cell growth and prevent collagen from depositing in the injured tissue.
There are two types of laser therapies for treating scar tissue: ablative and nonablative. A doctor will use ablative laser therapy to flatten scar tissue. Nonablative laser therapy can disrupt the blood supply in the scar tissue, which will eventually kill off the abnormal tissue.
Overall, researchers have shown that laser therapy demonstrates good results for surgical scars, hypertrophic scars, and keloids.
When a doctor chooses the appropriate type of laser therapy, people may notice improvements in the thickness of the scar, redness, itchiness, and texture.
Doctors sometimes recommend silicone treatments for scar management. After using silicon-based treatments, people may notice an improvement in the volume, elasticity, color, and firmness of hypertrophic scars and keloids.
Different silicone treatments are available, such as silicon gel sheet and creams that people can apply to the scar for 12 hours a day. People may need to use the treatments for 12 to 24 weeks before seeing any results.
People can apply dressings onto the scar tissue that apply pressure. Mechanical pressure can also reduce blood supply to the scar tissue, which will help to flatten the scar.
These dressings are uncomfortable, and people need to wear them for at least 23 hours a day for 6 months.
Unfortunately, researchers have shown that pressure therapy may offer only slight improvements in scar height.
Adhesive microporous hypoallergenic paper tape
Researchers have noticed that people have a higher incidence of developing a hypertrophic scar on an area of the body that is under increased skin tension. Another method to reduce the formation of scar tissue is a nonstretch adhesive microporous hypoallergenic tape.
This tape can help reduce tension across a wound and may prevent scar tissue formation.
Does massage help?
Research into the benefits of massage for scar tissue is ongoing.
Scar massage is a technique that healthcare professionals use in hospital burn units to improve the function and appearance of scarring caused by burns. The evidence is weak, but some experts believe that scar massage helps to improve and maybe even prevent hypertrophic scars.
Anyone considering massaging their scar should discuss it with a doctor first, particularly if they have had stitches or other surgery.
One study evaluated the evidence supporting scar massage. Although scientists need to carry out further research to confirm these results, researchers state that scar massage on hypertrophic burn scar tissue may improve the following:
- scar height
There are no standard scar assessment tools for researchers, and massage techniques may differ from one study to the next. Researchers need to conduct controlled, clinical trials on the effectiveness of massage for managing scar tissue.
There are several different treatments that doctors can use to prevent and treat scar tissue. However, no treatment is universally successful.
Doctors have many options to choose from when treating scar tissue, but some treatments are more effective for certain types of scars. Doctors should also address the psychological effects and movement restrictions that scars can affect some people.
Doctors should make people aware of the often limited success rates of scar tissue therapy and set realistic goals with them.