91 Mills, Amer. Journ. Med. Sci., Oct., 1878.

Perforating ulcer of the foot begins on the sole, beneath any of the metatarso-phalangeal articulations, preferably the first or the fifth, or under the heel, as a small pustule under the epidermis. This ruptures, and the ulcer which results begins to extend in a direction vertical to the surface, involving the deeper tissues or even opening into the joint and destroying the bone. It appears rather like a sinus than an ulcer, and is remarkable from the fact that it is not painful and is insensitive to touch, although it may prevent the patient from walking on account of extreme tenderness. The epidermis around the sinus is thickened and insensitive, and there may be anæsthesia of the entire sole of the foot, and even of the leg, although this is due to the neuritis present, which is also the cause of the ulcer, rather than to the ulceration. The circulation is sluggish in the affected extremity; it becomes cyanotic on exposure to cold, and seems peculiarly liable to become œdematous. The œdema may go on to suppuration, and involve the articulations, and ankylosis of the smaller joints may follow. This, too, is to be traced to the neuritis. The skin of the foot becomes pigmented, and may be dry or covered with offensive sweat. As the patient cannot walk while the ulcer remains, the condition demands treatment. Rest, moist warm applications, antiseptic lotions, scraping out the sinus, and other surgical means appropriate to the treatment of ulcers and sinuses do not often prove of benefit, and in obstinate cases recourse has been had to amputation of the foot. Electrical treatment has been tried in vain.

Such perforating ulcers may occur symmetrically on both feet, and may be numerous. They also occur rarely on the hands. They have been observed not infrequently in locomotor ataxia, occurring either early or late in the disease,92 and have appeared in patients suffering from dementia paralytica. The only constant lesion found is a degeneration of the peripheral nerve supplying the affected part.

92 For bibliography see Ross, Diseases of Nervous System, 2d ed., i. p. 256, and Blum, Berliner klin. Wochen., 1875, Nos. 13-15.

Acute bed-sores (decubitus) develop in many cases of spinal and cerebral disease, but not in all. It is argued that anæsthesia of a part or simple pressure upon a part or irritation of an anæsthetic part will not explain their occurrence, and that they must be traced to a destruction of trophic centres in the cord or brain. No amount of attention to the position and cleanliness of the patient is thought to be sufficient to prevent them in some cases, and their progress is often so rapid as to remove them from the category of simple ulceration. Their most frequent seat is upon the buttocks, over the sacrum, on the heels, and over the scapulæ; but it is believed that in the conditions in which they appear in these places pressure on any part may cause one. They begin within a few hours after the occurrence of the lesion as irregular mottled patches of redness, in which there soon appear small or large vesicles filled with dark serum. These rupture, leaving little areas of ulcerated surface, which soon unite to form a large ulcer with softened, infiltrated, and bloody base and ragged edges. The tissues around and within the ulcer have a tendency to slough and to become gangrenous, and the process goes on rapidly until a considerable area of the surface is completely destroyed, together with the deeper structures, fat, muscles, and fasciæ, down to the bone, which may become necrosed. Acute cystitis is so frequently associated with acute bed-sore that it is traced to the same nervous cause, though here, again, another explanation is possible. The constitutional disturbance produced by these two affections may be increased by a true septicæmia, to which the patient succumbs; or metastatic abscesses may be formed, and pyæmia cause death; or, lastly, the ulcer on the back may lay bare the vertebræ and erode their ligaments, thus opening a way for the extension of suppuration to the meninges of the spinal cord. The duration may be from a few days to two weeks, and the prognosis is very grave.

Chronic bed-sores develop in a similar manner, although all the processes described occur more slowly and are much less severe. They do not show the tendency to extend so widely or so deeply, nor to become gangrenous. They remain stationary after attaining a certain size, and the tissues seem to lack all tendency to reproduction and repair. When the central lesion which they follow begins to pass away they heal; sometimes local treatment is successful; but in many cases they persist for years, always threatening the life of the patient from the possibility of their sudden aggravation or from the occurrence of the complications already mentioned in connection with the acute process.

Since neither form of decubitus occurs after lesion of the anterior cornua of the spinal cord, nor in sclerosis of the posterior or lateral columns, nor in those cases of locomotor ataxia in which extensive invasion of the posterior cornua is present, while they are particularly frequent as a complication of general myelitis, hemorrhage in the cord, and syringo-myelitis, it is argued that the trophic centres whose destruction is the cause of these bed-sores lie in the central gray matter of the cord, near to the central canal. In unilateral lesion of the cord the bed-sore occurs on the anæsthetic side of the body—i.e. on the side opposite to the seat of the lesion—a fact which may indicate a decussation of the trophic nerve-fibres in the cord,93 but which has also been urged in proof of the theory that the sore is always due to irritation of an insensitive surface.

93 Recklinghausen believes that these cases of disturbance of nutrition can be explained by injury of anæsthetic parts in which vaso-motor disturbances of central origin exist (Handbuch d. Path. d. Ernahrung, pp. 236, 237).

The treatment of bed-sores belongs to the domain of surgery, the same methods being pursued as in the case of any large ulcer. The application of electricity to the sore has been tried, but the results are not sufficiently encouraging to warrant its recommendation.

Joint affections of neurotic origin are discussed in the articles upon Locomotor Ataxia, Hemiplegia, and Hysteria.