Scars are like a mirror of our lives. They are a visible sign of traumatic experiences and accidents that one has survived, but they can also tell a story about crises that were overcome and important turning points in a person’s life. Learn here about what a scar actually is, how scars form and what types of different shapes scars can take on.
Scars form after skin is injured. Generally speaking, the term scar is used to describe either a closed wound that is undergoing a healing process or any visible traces of a wound that has already healed.
In medical terms, a scar is simply coarse and fibrous replacement tissue. This tissue is formed by connective tissue cells during the healing process in order to close up gaps that form in the skin after an injury. A distinction is made between active or immature scars and mature scars.
Every skin injury leaves behind marks in the form of scars. If an injury is only superficial or minor, these scars are often barely noticeable. If a large section of the skin is affected or the injury extends to the deep layers of the skin, this can lead to very distinct scars and noticeable hindrances in day-to-day life. Every person deals with their scars differently, with the story behind the scars playing a major role here. The aim of scar therapy should not just be to regain mobility, but also to restore aesthetics. Be they large or small, scars can have a major effect on a person’s quality of life. That’s why it makes sense to treat scars, and especially fresh ones, as the chances of being able to influence scar quality in a positive manner are particularly favourable in the early stages of scar formation.
There are all different kinds of causes of skin injuries that lead to scar formation during the healing processes. A distinction is primarily made here between traumatic wounds caused by external force and iatrogenic wounds that occur as a result of medical treatment.
If our skin is damaged, our organism tries to repair it. The primary task of newly formed tissue here is to close the wound quickly in order to prevent foreign substances and pathogens from entering the body. In terms of appearance and functionality, however, scar tissue does not display the characteristics of the original skin. For example, it’s not as soft, it’s less elastic and it dries out more quickly than normal skin. In the case of superficial injuries that only affect the epidermis, wounds can heal completely without leaving any marks (epithelial wound healing). These types of injuries to the epidermis include sunburn and superficial abrasions. If deeper layers of skin are affected, such as in the case of surgeries etc., scars are formed after the various stages of wound healing. The wound healing process depends on the type, size and depth of a wound, but also on the genetic make-up of the person in question.
If one wants to understand how scars form, it’s helpful to take a closer look at the basic characteristics and functions of the skin, as well as the wound healing phases of the skin in connection with an injury.
With a total area of between 1.5 and 2 square metres, the skin is the human body’s largest organ. It also has the greatest number of nerves and accounts for up to 20% of body weight. The skin performs numerous complicated bodily functions such as regulating heat, protecting the body against infections and environmental influences, and preventing the body from drying out. It thus helps maintain the body’s inner balance and the exchange of substances within the body and its cells.
Yet skin is much more than “just” an organ, as skin is also our contact with the outside world – it has a representative function and serves as a protective barrier and even a communication tool. All types of touch are sensed by the skin’s surface, and this surface is also a means of perceiving and expressing sensations and feelings. Indeed, there’s a reason why we refer to skin as the “mirror of life”. Many changes in one’s body, personal lifestyle and mood, as well as hormone fluctuations, become visible in the skin.
The structure of skin is complicated. The skin’s structure is the same throughout the entire body. The skin consists of three layers: the epidermis, the dermis and the subcutis. These layers have different functions. The thickness of the skin differs depending on the area of the body. Skin on your face or the back of your hand is much thinner than that on your thigh, for example. The number of hair roots and sensory cells, such as temperature, pain and touch receptors, also varies.
Epidermis: Protection and immune organ
Despite being very thin, the top layer of the skin (epidermis in Latin) acts as the body’s protective shield. The epidermis is the layer that people perceive as skin. It is responsible for protecting the body from various external influences such as UV rays or pollutants. An intact epidermis stops microorganisms like bacteria from getting into your body and prevents your body from drying out. The epidermal cells constantly renew themselves and have a life cycle of approximately one month, at which point they die and detach themselves from the skin’s surface layer.
Dermis: Network and transport system
Attached to the epidermis, the dermis is situated directly beneath. It is thicker than the outer layer of skin and is very strong, elastic and tear-resistant owing to its collagen and elastin fibres. Unlike the epidermis, this layer comprises nerve cells, blood and lymph vessels. Among other things, the dermis is responsible for sensing touches such as stroking, pressure, pain, temperature or even itching. The blood vessels in the dermis also regulate the skin’s heat.
Subcutis: Fat storage and insulating layer
The subcutis primarily consists of fatty tissue that stores energy, protects the body against the cold and acts as padding. This skin layer varies in thickness depending on where it is in the body. The body’s hair roots, sebaceous and sweat glands can also be found in the subcutis.
Good to know
1. Cleaning phase (inflammation phase)
1. Cleaning phase (inflammation phase)
In the cleaning (or inflammation or exudation phase), blood clotting sets in immediately after the injury, which stops the bleeding from the wound. While this is happening, the body also releases a wound secretion that removes impurities and germs from the wound and also prevents these from entering the wound and the body. This phase can last for up to three days.
2. Granulation phase (proliferative phase)
2. Granulation phase (proliferative phase)
The body starts to rebuild vessels and tissue around 3 days after an injury. The purpose of the granulation tissue that forms as a result is to fill in any gaps in the skin and to close the wound as quickly as possible. The granulation phases lasts around 10 days.
3. Repair phase (epithelisation)
3. Repair phase (epithelisation)
The last phase – the closing of the wound at the epidermis and the beginning of scar tissue formation – starts between five and ten days after a wound is sustained. The repair phase can take several weeks or months to complete.
Sometimes, the scars formed in the repair phase do not just give rise to an aesthetic problem. Due to thickening, shrinkage and hardening of the skin, it has less elasticity at the scarred sites. This can lead to restrictions of movement and function, which can be accompanied by itching and pain as well.
Good to know
Scars are generally divided into three sub-groups based on their characteristics.
Hypertrophic scars
Hypertrophic or raised scars generally form as a result of a disruption to scar maturation that leads to the formation of an excessive amount of connective tissue. Depending on how they manifest themselves, raised hypertrophic scars can also be reddened or bulging. They form in the original affected area and do not spread beyond that area.
Keloid scars (keloids)
In keloids, the proliferation of connective tissue is even more extensive and uncontrolled than is the case with hypertrophic scars. That’s because the scar tissue grows very visibly beyond the original affected area. Keloids can be triggered even by tiny wounds like insect bites. The uncontrolled and heavily excessive growth of the connective tissue usually doesn’t occur until months after the injury, and it eventually stops after some time.
Atrophic scars
Atrophic scars develop when not enough new connective tissue forms to completely fill up the wound during the healing process. Here, slow or poor healing causes the skin to sink, leading to the formation of visible dents, craters or depressions. A typical example of atrophic scars are the depressions that form in the facial skin of people who previously had severe acne. So-called growth scars and stretch marks are also part of the group of atrophic scars.
Burns usually lead to raised hypertrophic scars. However, depending on how they develop, they can also result in sunken atrophic scars, or keloids. Burns are divided into three degrees based on the severity of the burn in question. In the case of first-degree burns, only the first layer of the skin is affected and the burn scars can usually heal completely. Second-degree burns involve the formation of burn blisters, whereby the middle layer of the skin is also affected here. Second-degree burns are also subdivided into second-degree 2a and 2b burns, whereby second-degree 2a burns can heal on their own, while second-degree 2b burns require surgery. Third-degree burns destroy the lowermost layer of the skin. Many burn scars also develop into sclerotic scars.
Sclerotic scars
In the case of sclerotic scars, the connective tissue that forms shrinks and contracts. This leads to the formation of hardened rigid scars that are not sufficiently elastic and can therefore also lead to noticeable limitations in terms of physical functionality. This is why the treatment of sclerotic scars focuses on the recovery of mobility.
No two scars are the same. If you were to monitor the healing of two identical wounds on different people, the resulting scars would not be exactly the same. A scar, and its appearance and development, depends on all manner of factors – some of which can be influenced.
Location
Scars on parts of the body that are often moving are constantly under strain. The continuous tension can lead to the development of undesirable scar formations.
Age
Wound healing is often impaired in elderly people, owing to a change in skin structure. Skin becomes less elastic, there are fewer layers of fat and the blood supply decreases. Children and young people tend to have thicker and more bulging scars as there is often an overproduction of new connective tissue.
Skin thickness
Thicker skin forms more visible and distinct scars. Skin thickness starts to increase in childhood and then decreases again from the age of 65.
Skin type and origin
People of African or Asian descent are prone to scarring and an overgrowth of scar tissue resulting from an excessive production of new connective tissue.
Other illnesses
Accompanying illnesses or pre-existing conditions (impaired circulation, diabetes, etc.) negatively affect scarring.
Important
Scar tissue can change for up to two years after its formation. During this time, it is possible to exert a positive effect on the development of a scar by ensuring the right care and treatment. Find out more now about how scars are treated.