A hypertrophic scar is a
cutaneous condition
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of thi ...
characterized by deposits of excessive amounts of
collagen which gives rise to a raised
scar
A scar (or scar tissue) is an area of fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other organs, and tissues of the body. Thus, scarring is a n ...
, but not to the degree observed with
keloids.
Like keloids, they form most often at the sites of pimples,
body piercings, cuts and burns. They often contain nerves and blood vessels. They generally develop after thermal or traumatic injury that involves the deep layers of the
dermis and express high levels of
TGF-β
Transforming growth factor beta (TGF-β) is a multifunctional cytokine belonging to the transforming growth factor superfamily that includes three different mammalian isoforms (TGF-β 1 to 3, HGNC symbols TGFB1, TGFB2, TGFB3) and many other sign ...
.
Cause
Mechanical
tension
Tension may refer to:
Science
* Psychological stress
* Tension (physics), a force related to the stretching of an object (the opposite of compression)
* Tension (geology), a stress which stretches rocks in two opposite directions
* Voltage or el ...
on a wound has been identified as a leading cause for hypertrophic scar formation.
When a normal wound heals, the body produces new collagen fibers at a rate which balances the breakdown of old collagen. Hypertrophic scars are red and thick and may be itchy or painful. They do not extend beyond the boundary of the original wound, but may continue to thicken for up to six months. Hypertrophic scars usually improve over one or two years, but may cause distress due to their appearance or the intensity of the itching; they can also restrict movement if they are located close to a joint.
Some people have an inherited tendency to hypertrophic scarring, for example, those with
Ehlers–Danlos syndrome.
Prevention
It is not possible to completely prevent hypertrophic scars, so those with a history of them should inform their doctor or surgeon if they need surgery.
Management
A 2021
systematic review brought together evidence from different studies that investigated using silicone gel sheeting to treat hypertrophic scars. 13 studies with a total of 468 participants were reviewed in total. Many different treatments were included but it was uncertain whether silicone gel sheets were more effective than most of these. Silicone gel sheets may improve the appearance of scars slightly compared with applying onion extract, and may reduce pain compared with no treatment with silicone gel sheets or pressure garments.
A 2022
systematic review included multiple studies on laser therapy for treating hypertrophic scars. There was not enough evidence for the review authors to determine if laser therapy was more effective than other treatments. They were also unable to conclude if laser therapy leads to more harm than benefits compared with no treatment or different kinds of treatment.
Scar therapies, such as
cryosurgery
Cryosurgery is the use of extreme cold in surgery to destroy abnormal or diseased tissue; thus, it is the surgical application of cryoablation. The term comes from the Greek words cryo (κρύο) ("icy cold") and surgery (''cheirourgiki'' – χ ...
, may speed up the healing process from a hypertrophic scar to a flatter, paler one.
Early hypertrophic scars should be treated with applied pressure and massage in the first 1.5–3 months. If necessary, silicone therapy should be applied later. Ongoing hypertrophy may be treated with corticosteroids injections. Surgical revision may be considered after 1 year.
See also
*
Keloid
*
List of cutaneous conditions
References
{{Localized connective tissue diseases
Dermal and subcutaneous growths