Introduction
The human skin consists of a multitude of layers, each of which has a different structure, as each of them has a different function to fulfil. The outermost layer of the skin, the so-called epidermis, is further subdivided into five layers: from the inside out, these are the
- Basal layer
- Sting cell layer
- Grain layer
- Gloss layer and
- Horny layer (stratum corneum)
The majority of cells in the epidermis are formed by the horny cells (keratinocytes), which gradually develop into the horny cells (corneocytes). The cornea consists exclusively of corneocytes.
These cells are actually already dead and therefore no longer contain any cell organelles (cell nucleus, mitochondria, etc.). Between the individual cells there are fats which help to support the protective function of the corneal layer. Normally, the horny cell layer consists of 12 to 200 layers, depending on which part of the body the skin is examined.
Further inside, the individual cells (with the help of so-called desmosomes) still form contacts with each other, further towards the surface, in the outermost layer of the horny layer, also known as the stratum disjunctum. When the cell contacts break down, the individual horny cells can detach from each other and be removed from the skin. This process is quite natural and necessary to gradually renew the skin.
It normally takes place without these exfoliations being visible to the human eye. Only if there is a disorder in the process and as a result aggregates of 500 or more cells are detached from the skin at once, can this be seen in the form of skin flakes. The cornea has an extremely important task for our body.
It practically forms a barrier between the human body and the outside world. Thus, on the one hand, it serves as protection against external influences. Bacteria, viruses and other germs must first overcome the skin barrier in order to penetrate the body, a hurdle on which many of the microorganisms already fail.
But our cornea also protects us from mechanical stress: Regions that are exposed to increased pressure or friction react with an increased production of cornea. With the help of the fats that are stored between the corneal cells, the cornea also performs another important task: it is water-repellent and thus protects the body from unnecessary water retention and dehydration. From the above mentioned facts it follows that a relatively thick cornea is classically found on the soles of the feet, because you constantly walk on it.
On the other hand, a thick callus can also appear in unusual places on the foot, for example by wearing shoes that are too tight or wrong. Even the frequent playing of stringed instruments such as a guitar can lead to calluses on the fingertips. It is therefore clear that, in principle, any area of the skin can react with excessive callus production if the appropriate stress conditions are present.
In rare cases, however, the overproduction of cornea can exceed a normal, healthy level and thus become pathological and even possibly dangerous. Then the thickened cornea is a sign of a chronic inflammation of the skin (dermatitis) and is often scarred. This is then referred to as callus or skin callosity or tyloma.
Probably the best known example of this is the corn. A corn eye is a growth of the cornea (hyperkeratosis). This is usually round and between 5 and 10 millimeters in size.
In its center there is a mostly yellowish translucent horny wedge (which represents the “eye”), the tip of which is directed into the depth and which can cause pain by exerting pressure on the deeper lying tissue. The deeper this spur reaches, the more painful the corn usually is. Callosity is caused by the fact that the corresponding part of the body tries to protect itself better from external influences by means of thicker, harder skin.
The most common trigger is chronic pressure or friction, especially on skin close to the bone. On the sole of the foot, they usually occur near the heads of the metatarsals. On the toes, corns are often found near the toe joints.Corns do not usually pose a further health risk and are therefore usually only treated if there is an increased risk of complications or if they cause a pronounced feeling of discomfort in the patient.
It is not normally necessary to remove corneas, as they are a natural part of the body and help protect the deeper tissues. Even if it is thicker in some places than in others or than is considered “normal”, there is usually no need to remove the cornea. The only exception are corns, if they are accompanied by a high risk of complications (see above) or if the cornea is accompanied by tears in the skin, which, especially if they reach the blood vessels, can sometimes be very painful.
However, many people find a visible cornea unpleasant and unattractive, which is why they would like to remove it. However, it is important to understand that this can be a lengthy process and by no means an overnight process. As long as it takes for the cornea to form (on average, a layer of cornea a few millimeters thick takes about a few weeks to form), you should plan for it to disappear completely.
There are several possibilities for this, which should be used depending on the degree of corneal development and individual preferences. First of all, of course, one should try to find out if it is not possible to get rid of the cornea completely without the use of external aids. This means that if you suffer from increased calluses on your feet, you should start by wearing comfortable and not too tight shoes and also avoid standing on the spot for long periods of time.
Shoes that are too warm can also promote the development of calluses through increased sweating of the feet. In order to prevent the development of calluses, exercise in particular helps, as does massaging the foot to achieve good blood circulation and thus prevent calluses. If this is an option depending on the season, it is always a good idea to walk barefoot to prevent calluses.
In general, it is a good idea to care for your feet by regularly using ointments, lotions, foams or creams to keep the skin moist and supple. The simplest method and especially good for not too thick layers of callus is to remove the excess callus mechanically. However, one must always be careful not to cause any damage with the appropriate tools.
It can happen very quickly that you injure yourself with the sharp tools and cause an inflammation to develop. Probably the gentlest way is to use a pumice stone or sandpaper, both of which remove only the smallest areas of skin at once and are therefore a particularly gentle way of removing calluses. It is particularly effective if the pumice or sandpaper is used after a footbath, as the skin is then already softened and excess calluses can be removed even more easily.
This footbath can simply be done in warm soapy water, but there are certain additives that can be added to make the result even better. These include old household remedies such as apple vinegar or more recent discoveries such as tea tree oil or the juice of the aloe vera plant. The same effect as a footbath is achieved by applying hot chamomile packs.
In any case, one should avoid using too radical mechanical methods. For example, one should definitely refrain from simply cutting off even thicker corneal areas with scissors. On the one hand, this causes severe damage to the skin and, on the other hand, it has the negative side effect that the cornea usually grows back even more strongly.
Also with planes and similar devices one must always handle carefully, in order not to hurt the skin and thus cause more damage than finally removing calluses. After using the above mentioned products, it is best to apply some more cream to the feet, for example deer sebum or marigold ointment, but in principle any moisturizing foot cream is suitable. In addition to the above mentioned helpful household remedies, there are also special tinctures, ointments and plasters against calluses.
Most of these preparations contain salicylic acid and can be purchased in pharmacies.Salicylic acid has an antimicrobial effect, which is useful in the case of corneal treatment to prevent damaged areas of skin from becoming inflamed and colonized with germs, especially if they are more susceptible to external stimuli than they normally would be as a result of previous treatment measures such as planing or sanding. In addition, salicylic acid also has a keratolytic (horny) effect from a concentration of 5%. This effect is due to the fact that the substance which under normal circumstances ensures the cohesion between the individual cells is released by the acid, allowing the cells to be removed from each other and from intact skin.
From a concentration of 10%, salicylic acid is used for the treatment of corns and warts. These solutions must be applied locally to dissolve the horny layer. Here it is important that the healthy skin does not come into contact with the product over too large an area, otherwise it can be affected.
This is because salicylic acid has an acute irritating effect on the skin and mucous membranes, which means that it can cause If the acid is chronically exposed, it can even lead to disorders of the gastrointestinal tract. All other side effects known from salicylic acid, such as respiratory depression or liver or kidney damage, occur only when this drug is taken orally. Another common ingredient of corneal creams is urea.
This has a double positive effect on the excessive cornea: On the one hand it acts as a natural moisturizer. On the one hand, it acts as a natural moisturizer. Urea ensures that the skin cells can absorb and store more moisture.
Creams containing urea, which are only used against dryness, usually contain 3 to 20% urea. On the other hand, it also has a direct effect on the horny skin. To achieve this effect, higher concentrations of 40% are required.
Also often used are ointments containing collodion either in an alcohol or ether solution. Other corneous substances (the technical term for this is keratolytics) are
- Redness
- Itching and in the worst case even too
- Tissue damage
- Retinoids (for example adapalene and tretinoin),
- Azelaic acid
- Benzoyl peroxide and
- Fruit acids (for example lactic acid, mandelic acid and glycolic acid).
If the application of these lotions does not lead to an improvement or if you need professional assistance for other reasons, you can always consult a so-called podiatrist (a trained chiropodist) who is especially familiar with corns and calluses on the foot and who can arrange an individually adapted therapy or carry it out himself. A professional treatment is necessary and important, especially in the case of corns, and always has the goal of removing or dissolving the callus and thus removing it (e.g. with the help of tweezers).
If the corn has become infected, this inflammation is treated directly, which often requires the involvement of a doctor, since antibiotics must be used. If the lesions are very deep-seated, it may be necessary to remove them surgically. Even if certain toe or foot malpositions are the cause of the corns, this may be an indication for surgery.
If the cornea does not disappear despite all attempts at self-treatment and/or other symptoms occur, it should always be kept in mind that increased corneal formation can also be the expression of an underlying disease such as psoriasis, which in some cases may also manifest itself first or mainly on the feet. So if you are unsure about this, it is always a good idea to consult a doctor and ask for advice. There are also various home remedies for the cornea on the foot that can be used for its removal.
For example, various foot baths as well as a hot camomile compress can help soften the affected area. For this you need a cloth in which you put some chamomile flowers. Then you can pour some boiling water over it and then – after the cloth has cooled down a little – wrap the affected foot in it for about a quarter of an hour.
Once the cornea is softened, it can usually be rubbed off easily with a pumice stone. But foot baths with various natural additives can also have the same effect. Examples include tea tree oil, aloe vera juice or even apple vinegar.The footbath should then last for about five minutes and then use the pumice stone.
In addition, there are various ways to prevent corneal growth in the first place with very simple means. This is because calluses always develop when, in addition to mechanical stress, the skin is relatively dry and poorly cared for. Therefore, many procedures that are actually used for pure foot care can be considered for corneal prophylaxis.
On the one hand, regular application of cream and sufficient moisture can make the skin on the feet more resistant. Creams containing urea with a urea content of more than ten percent can additionally counteract the development of calluses. A peeling can also prevent calluses and – if carried out regularly – can gradually make calluses disappear.
Common household remedies such as olive oil with sugar can be used for peeling. For this purpose, a mixture of some olive oil and a few tablespoons of sugar should be prepared first, so that the consistency of this mixture is rather coarse-grained. The feet should be washed and dried beforehand so that any impurities are not transported into the skin.
Then the feet can be massaged with the oil-sugar mixture and after a few minutes rinsed again with lukewarm water. Last but not least, the footwear should not have any additional pressure points and in case of a foot malposition, the use of insoles can also provide some relief. The callus becomes unpleasant when it becomes dry and cracked.
Creams from various manufacturers can help against this. When buying such a cream you should make sure that the cream contains urea. Urea is urea and is also produced by the body itself as it breaks down the amino acids that make up protein.
Therefore, allergic reactions to creams containing urea are extremely rare. Due to its chemical composition, urea is able to bind a lot of liquid and is therefore not only suitable for the treatment of cornea but also as a hand cream. In order to achieve an effective removal of the cornea, creams containing salicylic acid should also be used.
The combination of urea and salicylic acid ensures that the skin is softened by the urea and removed by the salicylic acid. The acid acts like a peeling. Vaseline can also be applied to increase the suppleness of the feet.
The creams can also be applied as a prophylaxis for feet that are not yet very severely keratinized. The thinner the callus, the better the creams help. However, if the cornea is very thick, a pumice stone should be used in addition to the creams.
If small tears (rhagades) have already appeared, care should be taken when applying the cream to ensure that not too much of the cream gets into the open wound, as this can sometimes lead to infections. Before applying the cream, the wounds should also be cleaned and disinfected if possible. In the case of not very severe forms of calluses, creams from the drugstore can already help, while in the case of very severe forms, creams from the pharmacy can also help in consultation with a doctor. In general, one should first try to get a grip on the cornea with mild creams from the drugstore before resorting to the creams from the pharmacy as ordered by a doctor.
