Part 54

#Describe the clinical appearances.#

Callosities are most common about the hands and feet, and consist of small or large patches of dry, grayish-yellow looking, hard, slight or excessive epidermic accumulations. They are somewhat elevated, especially at the central portion, and gradually merge into the healthy skin. The natural surface lines are in a great measure obliterated, the patches usually being smooth and horn-like.

Keratosis palmaris et plantaris (symmetric keratodermia), as regards the local condition, is a somewhat similar affection. It consists of hypertrophy of the corneous layer of the palm and soles, usually of a more or less horny and plate-like character, but is congenital or hereditary, and not necessarily dependent upon local friction or pressure.

#Are there any inflammatory symptoms in callositas?#

No; but exceptionally, from accidental injury, the subjacent corium becomes inflamed, suppurates, and the thickened mass is cast off.

#State the causes of callositas.#

Pressure and friction; for example, on the hands, from the use of various tools and implements, and on the feet from ill-fitting shoes. It is, indeed, often to be looked upon as an effort of nature to protect the more delicate corium.

In exceptional instances it arises without apparent cause.

#What is the pathology?#

The epidermis alone is involved; it consists, in fact, of a hyperplasia of the horny layer.

#State the prognosis of callositas.#

If the causes are removed, the accumulation, as a rule, gradually disappears. The effect of treatment is always rapid and positive, but unless the etiological factors have ceased to act, the result is usually but temporary.

#How is callositas treated?#

When treatment is deemed advisable, it consists in softening the parts with hot-water soakings or poultices, and subsequently shaving or scraping off the callous mass. The same result may also be often effected by the continuous application, for several days or a week, of a 10 to 15 per cent. salicylated plaster, or the application of a salicylated collodion, same strength; it is followed up by hot-water soaking, the accumulation, as a rule, coming readily away.

#Clavus.# (Synonym: Corn.)

#What is clavus?#

Clavus, or corn, is a small, circumscribed, flattened, deep-seated, horny formation usually seated about the toes.

#Describe the clinical appearances.#

Ordinarily a corn has the appearance of a small callosity; the skin is thickened, polished and horny. Exceptionally, however, occurring on parts that are naturally more or less moist, as between the toes, maceration takes place, and the result is the so-called soft corn. The dorsal aspect of the toes is the common site for the ordinary variety. The usual size is that of a small pea. They are painful on pressure, and, at times, spontaneously so.

#State the causes.#

Corns are caused by pressure and friction, and may usually be referred to improperly fitting shoes.

#What is the pathology of clavus?#

It is a hypertrophy of the epiderm. Its shape is conical, with the base external and the apex pressing upon the papillæ. It is, in fact, a peculiarly-shaped callosity, the central portion and apex being dense and horny, forming the so-called core.

#Give the treatment of clavus.#

A simple method of treatment consists in shaving off, after a preliminary hot-water soaking, the outer portion, and then applying a ring of felt or like material, with the hollow part immediately over the site of the core; this should be worn for several weeks. It is also possible in some cases to extract the whole corn by gently dissecting it out; the after-treatment being the same as the above.

Another method is by means of a ten- to fifteen-per-cent. solution of salicylic acid, in alcohol or collodion, or the following:--

Ac. salicylici, ...................... gr. xxx Ext. cannabis Ind., .................. gr. x Collodii, ............................ fiv. M.

This is painted on the corn night and morning for several days, at the end of which time the parts are soaked in hot water, and the mass or a greater part of it, will be found, as a rule, to come readily away; one or two repetitions may be necessary. Lactic acid, with one to several parts of water, applied once or twice daily, acts in a similar manner.