Depending on appearance and histological structure, scars are divided into normotrophic, atrophic, hypertrophic and keloids. The last to types refer to the group of pathological scars.
Normotrophic scars are leveling with the surrounding skin are the most harmless by nature (scar removal techniques). They are formed as a result of an adequate reaction of the organism to the injury. Later they become thin, whitish and do not cause physical discomfort to the bearer. Such scars typically do not require correction, apart from the cases of aesthetical improvement of scar appearance or acceleration of colour normalization process.
Fig.1. Normotrophic scars after surgery
Atrophic scars are below the skin level are often the result of injury or inflammation (atrophic scar reduction treatment). Atrophic scars are subdivided into the types as follows: ice pick scars (Fig.2.A); boxcar scars (Fig.2.B) and rolling scars (Fig.2.C)
Fig.2. Types of Atrophic Scars
Ice pick scar
The skin above the atrophic scars is thin, loose and often with cross-striation. Such scars are usually devoid of pigment and therefore look white. The characteristic appearance of these scars is stipulated by connective tissue defect under beneath the scar, collagen and elastin deficiency – principal proteins forming the skin matrix.
Keloid and hypertrophic scars
Hypertrophic scar, like keloids, overtop the surrounding skin, but do not lap over the damaged area. Collagen fibres acting as the scar substrate are wide and callous, but are located roughly on the parallel level with the skin surface (Fig.3.). Usually hypertrophic scars are formed after surgical procedures and injuries of the flexible skin areas (of the joint area, for instance) resulting from serious inflammation, consecutive infection, decrease of local immunity, endocrine dysfunction, to mention a few (removal keloid and hypertrophic scar).
Fig.3. Hypertrophic scar of achilles tendon area
Fig.4. Post-burn keloid scars
Keloid scars or keloids exceed the size of initial wound significantly. Keloids after piersing is the main reason to occur in the ears region. By a keloid is observed massive proliferation of connective tissue in the areas of burns, wounds, post-acne (acne keloid scars) and post-surgery injuries. Collagen fibres in keloid scars are located chaotically and node-like, resembling a fingerprint (Fig.4.) Despite their age, keloids can be active (growing) and inactive (stabilized). An active keloid scar grows and causes pain, itching, numbness, emotional distress, and looks like a strained red scar, often with a bluish tint. Inactive keloid is not growing and does not bother the bearer from the subjective perspective, has a pink colouring or the one close to the colour of normal skin. Keloids are typically localized in the regions of ear lobe, decollate (chest), shoulders and back (removal keloid and hypertrophic scar)