Obrázky stránek
PDF
ePub

Over the front the knee and behind the elbow joint, they can be cut longer and with less danger of sloughing than in any other part of the body. Sometimes the slightest slip of the knife will imperil the life of a flap, as in Syme's amputation, while fashioning the heel flap, or in a Farabeuf's amputation at the seat of election, while cutting the external flap, the anterior tibial artery may be cut where it is penetrating the interosseous membrane. All blood vessels must be divided terminally. It is usually a bad practice to tie the main artery at a higher point to prevent bleeding, although this is at times advisable and necessary in certain amputations at the hip joint. Where the flaps are transfixed, care must be taken not to split the blood vessels longitudinally.

3. Make a choice of the best method of covering the bones. We must naturally ask the question, "What will be expected from the amputation stump? What service will it be called upon to perform?" If it is to receive terminal pressure, the scar must be laterally placed; if lateral, the scar must be terminal. Again, it would be absurd to remove the end of the metacarpal bone, after disarticulation, if the patient were a laborer; whereas, if he were a rich man, this would be perfectly justifiable and would give an excellent cosmetic result.

The best solution, in each individual case, can only be reached by a thorough knowledge of all of the classical procedures, from which a choice can be made. It must be acknowledged that the crystallized knowledge of generations of surgeons is better than the solitary inspiration of a novice. In no class of work is it more necessary to be master of the exact details. We must make our choice of a method, and proceed to execute it with the precision of a tailor, the knowledge of an anatomist and the skill of a surgeon. As time passes, new methods will be introduced; but rarely as inspirations. Farabeuf himself, in his preface to the description of his operation at the seat of election, says: "I have dissected legs by the hundreds before arriving at the details of the following operation."

I would lay down the rules of amputations in the following way:

Given ordinary conditions, as in amputations for disease, the flaps should be fashioned as closely as possible according to the classical procedures. In the hand and foot, and in amputation near the joints, we can rarely deviate with advantage from the recognized methods, although many trimming operations can and must be resorted to.

1. Speaking generally, we may say that in the forearm, arm, leg and thigh, the sum total of the lengths of the flaps must be at least one diameter and a half, measured through the limb at the point where the bones are to be divided. The diameter must be taken in the direction the flaps are expected to lie. If the flaps are anterior and posterior, the diameter is an anteroposterior diameter; it lateral, a lateral diameter. These measurements may be a little too short, under certain circumstances. These are: (1) When the section of the bones is large compared with that of the soft parts. Lower end of radius and femur. Upper end of tibia. (2) In cases where the limb is inflamed or oedematous, and secondary retraction is to be feared. (3) Where the amputation is performed a long distance from the root of the limb; just above the elbow, wrist, knee or ankle.

2. The flaps must be carefully measured. There is no excuse for not doing this. The period when it was considered the proper thing to lop off a limb with the rapidity of lightning, has long passed. It is only after long practice that a surgeon acquires the skill to fashion the flaps with his eye alone. I have only seen one man who could even approach this degree of skill, and I have seen him cut out some sorry flaps.

3. The base of the flap (i. e., the shortest distance across the limb, between the origin and the termination of the incision, to mark out the flap), must always measure one-half of the circumference of the limb at that point. Failure to attend to this will prevent the flaps from coming into accurate apposition.

4. The incisions should always be made through skin and superficial tissue, and the flaps marked out. The integument should

then be retracted a little along the whole incisions before the muscles are divided.

5. The flaps are best fashioned by cutting each muscle separately from without inward. (There are, of course, exceptions to this rule, as previously indicated.) By this means we allow the more contractile muscles to retract first, and are then able to cut the others at the level of the retracted ones.

With this rather long preamble, I will now proceed to the description of an amputation which embodies nearly all of the qualities that go to make a good amputation stump. This is an operation at the seat of "election," described by Farabeuf.

The seat of election, as is well known, is a hand's breadth below the line of the knee joint. The tibia is sawed there and the sawline is usually just above the foramen for the nutrient artery. The directions are the following:

RIGHT LIMB.

1. Skin incisions. The external flap is U-shaped. The incision begins above opposite the saw-line and just internal to the tibial crest. It passes directly downward inside the tibial crest for about three inches, then curves downward and outward across the limb (the lower end being placed one transverse diameter below the starting point), then curves upward toward the posterior aspect of the limb, in a direction diametrically opposed to that it had in starting, until it reaches a point almost diametrically opposite the starting point. (The base of the flap must be half the circumference of the limb.)

The internal flap is marked out by an incision which starts from a point one and a half inches below the commencement of the anterior limb of the U, passes across the inner side of the limb and terminates at the upper end of the posterior limb of the U. The incisions at first concern skin only. Then the skin is loosened for about half an inch along the whole length of the incisions.

2. Cutting the muscles in the flaps. (a) Large external flap.

Insert the point of the knife at the upper end of the anterior incision and cut the aponeurosis from above downward along the line of the retracted skin. This must be done from end to end of the cut. The muscles then appear as if herniated. Insinuate the left forefinger between the tibia and the tibialis anticus muscle, and separate the muscles from bone as far as the interosseous membrane. Pull the extensor muscles outward and divide them obliquely toward the tibia and fibula, entering the knife at the level of the retracted skin. Cut the muscles to bone all around the incision and carefully raise the flap from the outer surface of the tibia, the anterior surface of the interosseous membrane and the outer surface of the fibula. The flap is lifted from the surface of the tibia and the interosseous membrane with the left forefinger, but it will be necessary to use the knife in separating it from the fibula. The greatest care must be used to protect the anterior tibial artery. It lies on the deep surface of the flap in its whole length, and upon it depends the vitality of the whole flap. It is better to guard it carefully with the finger during the time when the knife. is being used. It is nearer the fibula than the tibia, and it is during the separation of the peroneal muscles from their attachments that it is in danger. The flap must be thrown up as far as the level of the proposed saw cut.

(b) The internal flap. This can be cut conveniently by transfixion. The knife is entered at the upper end of the inner incision and carried carefully across the bones and interosseous membrane, emerging at the level of the retracted skin.

(c) Cleaning the bones. The uncut soft tissues must be carefully divided, and a transverse cut made in the interosseous membrane at the upper end. All the soft tissues and periosteum must be retracted as high as the level of the future saw cut.

(d) Division of the bones. Retract the flaps with a threetailed bandage. Saw the fibula at a slightly higher level than the tibia. Make an oblique cut on the anterior border of the tibia, entering somewhat higher than the proposed level of the main saw cut. Let it be carried about half-way through the bone. Then

withdraw the saw and enter it transversely at the level desired and cut straight through the bone. This will bevel the anterior edge of the tibia, and prevent it from projecting through the flaps.

(e) The scar lies on the inner surface of the limb, and is not terminal. This operation has stood the test of many years, and is now pronounced to be the best operation at the seat of election. The external flap is perfectly nourished, and forms a splendid pad for the end of the tibia. The scar is lateral and so situated that it is free from all pressure.

It is not as widely understood as it deserves to be, and if this communication is the means of bringing it to the notice of the profession, I am certain that they will find it the best of all the operations at this level.

« PředchozíPokračovat »