An organ, according to the anatomists’ definitions, is a structure of the animal body made up of a number of different kinds of cells and tissues, which are assembled for the performance of one or some-times several functions. Thus the liver is an organ made up of glandular cells, connective tissue, reticular cells, blood vessels, bile ducts, etc. Its functions are digestive, nutritional and excretory.
The hand is not generally classified as an organ, but might be so considered. At least in the sense that it is made up of a number of different kinds of tissues it falls into the definition. Its functions certainly are far more important than we casually realize. The human hand is one of the most beautiful instruments in the world, and has probably done as much to raise us above the level of the brutes as our “superior” brain.
Diseases of the hand are numerous, because of the many structures which go to the make-up of the organ. There is bone, skin, blood vessels, muscles, tendons, fascia.
Most organs have diseases which are consequent upon the particular sort of work they do or the exposure to which they are subjected, and this is true of the hand. The foot, with the same sort of structures in it, suffers mostly from the stress of weight bearing. The hand, which is constantly thrust into all sorts of messes, is more likely to suffer from infection, and the principal diseases of the hands are infections.
But the hand is a part of the human body and, therefore, shares secondarily in a great many diseases which are general to the body. Thus, for instance, we have characteristic changes in the skin of the hand in such a food deficiency disease as pellagra. A nervous disease of the spinal cord, such as syringomyelia produces trophic changes in the hand, with ulceration of the skin. Heart disease and chronic lung disease produce clubbing of the fingers and rounding of the finger nails. Diabetes may show up in the hand with the formation of fatty deposits called “xanthoma.” And such nervous diseases as produce tremor are particularly likely to appear in the hand.
A characteristic enlargement of the hand is due to a disease of the pituitary gland. In this disease, named “acromegaly,” the bones of the hands become enlarged, change its shape so that it is called “spadelike.” Of course, acromegaly produces changes in other bones, notably those of the jaw, but it is probably more easily detected in the hand than any place else. The patient frequently is aware of the progress of the disease only from the fact that he has to keep changing the size of his gloves, making them larger.
INFECTION OF THE HAND
The commonest disease of the hand is due to simple infection.
The reasons for this, as was pointed out yesterday, are quite obvious.
The hand is, in most cases, the instrument of contact with the external world. The skin of the rest of the body does not come into violent contact with external objects, at least, sufficiently violent to break the skin. In our state of civilization the skin of the foot is usually protected, but the hand bears the brunt of such contacts. The objects that we touch in the external world are usually dirtythat is to say, covered with germs, and when a cut, or piercing wound, or stab wound occurs, the germs are introduced under the skin in the deeper layers of fascia.
It is the distribution of these sacs, or fascial layers, which makes hand infection frequently so serious. The structure and work of the hand depend entirely upon the arrangement of these fascial layers so there is no getting away from it.
The fingers are moved by the muscles of the forearm. That is why they are so strong. These large muscles could not be incorporated in the hand itself, and have the organ small enough to function as it does. Therefore, long tendons go down from the muscle attachments in the arm, over the wrist, through the palm or back of the hand, to be attached to the base or tips of the fingers. These tendons are like pulley cords, and have to move and slip easily across each other and over the bones and other structures of the hand. In order to accomplish this Nature has surrounded them with a very delicate membrane, lubricated with fluid. But these membranes are, unfortunately, extremely sensitive to infection, and since they are inter-communicating, a stab wound as from a tack or ice pick, may dig into the tip of the finger and the infection there deposited, going down the fascial sacs, may end up as an abscess in the palm of the hand.
These infections are usually ordinary pus infections, but the most dangerous kind are those caused by the germs called “streptococcus,” which does not form a thick pus.
The remarkable thing about modern surgical treatment of these infections is how much of the function of the hand can be saved. Infection may occur, resulting in a great boggy, swollen, gangrenous looking hand, which would make one feel that amputation was necessary unless you knew that with conservative treatment and patient care, the hand would eventually return to normal. Perhaps not quite to normal, but at least to a good functional prehensile organ.
The basis of these treatments is to keep the hand and arm quiet in a splint, and at the same time apply large moist dressings, opening small abscess spots as they appear.
How INJURIES MAY OCCUR TO THE HAND AND WRIST
The hand and wrist are in an extremely exposed position to injury. Sprain is not so common as in the case of the ankle, but for a very definite reason fracture of the wrist is one of the commonest of fractures in the body. The reason is, of course, obvious that when one falls, it is natural to break the force by thrusting out the hand. The whole weight of the body is pounded down on the wrist, and it gives way at its weakest point.
This fracture was first accurately described by Abraham Colles in 1814 and is known as “Colles’ fracture.” Its history is a good illustration of the improvement we have made in the management of fractures of the bone in the hundred odd years that have supervened.
Abraham Colles was born in Kilkenny and practiced surgery most of his life in Dublin.
In describing this classic form of fracture he wrote: “I consider this by far the most common injury to which the wrist or carpal extremities are exposed. The fracture takes place about an inch and a half above the wrist.”
One gathers from this original description the difficulties that the surgeons of those days had in dealing with fractures. First, they had to guess and reason by logic and induction as to just what bone was broken and where the break was. Only if the patient died and it was possible to make a dissection of the part, could they determine by direct observation. And this did not happen very often.
Aseptic surgery had not been perfected, and it would have been putting the patient’s life in jeopardy from infection to cut down on the injured part during life.
Then Colles emphasizes the great difficulty of reducing the fracture and making it stay, on account of the pull of the muscles. When anesthesia was introduced 32 years later, it was possible to obtain relaxation so that the bones could easily and effectively be put in place.
Finally, we never knew whether, even after the bones had been approximated, they were going to stay in that position. The patient had to undergo the agony of having the splints removed and readjusted.
It was when the x-ray came into use in 1895 that the surgeon could see exactly what bone was broken and how it was broken or misplaced, and by taking x-ray pictures regularly during the course of healing, assure the fracture patient of freedom from deformity.
For a while Colles’ fracture was much more frequent than now, because it was the usual injury that came from cranking an auto-mobile. Since the cranking days are gone, the usual method of producing the injuryfalling on the palm of the outstretched handagain obtains.