A Manual of the Operations of Surgery / For the Use of Senior Students, House Surgeons, and Junior Practitioners

by Joseph Bell

In one word, it may be stated that, with the exception of those amputations performed through the lower third of the bone, the flap method is to be preferred, and the flaps should in almost every case be made by transfixion.

In the lower third, however, the flap method, though exceedingly easy, and capable of very rapid performance, has certain defects; the chief of these being the tendency which the muscular flaps (the necessary result of transfixion) have to cause undue retraction, and hence protrusion of the bone. This is seen specially in the hamstrings, which from the great distance of their origin, and the purely longitudinal direction of their fibres, retract to a very great extent, much more than the anterior muscles can do from the pennate direction of their fibres, and the manner in which they are mutually bound down to each other and to the bone.

Even in this one position, the lower third of the thigh, the methods that may be needed are various, and require separate notice;—for operations here are extremely frequent from the frequency of strumous disease of the knee-joint in our variable climate, and from the fact that compound fractures or dislocations of the knee-joint so very often necessitate amputation.

In cases where the skin over the patella is uninjured and available, the operation by long anterior flap (either by Teale's method, or by Mr. Spence's modification of it, which curiously is almost exactly similar to the amputation of Benjamin Bell by a single flap) is suitable enough. But, I believe, preferable to either of these is the operation of Mr. Carden, already described. In cases where the knee-joint is injured, and the skin over the patella unavailable, and yet where it is not necessary to go higher up the limb, the modified circular amputation of Mr. Syme will be found very suitable.

As it is in this lower third of the thigh that a very large proportion of the cases requiring a long anterior flap is to be found, it affords the best opportunity for comparing in their detail the three almost similar plans of B. Bell, Teale, and Spence—after which Mr. Syme's modified circular may be described.

Benjamin Bell's Flap Operation above the Knee (reported in his own words, slightly abbreviated).—"When this operation is to be performed above the knee, it may be done either with one or two flaps, but it will commonly succeed best with one. The flap answers best on the fore part of the thigh, for here there is a sufficiency of the parts for covering the bones, and the matter passes more freely off than when the flap is formed behind.... The extreme point of the flap should reach to the end of the limb, unless the teguments are in any part diseased, in which case it must terminate where the disease begins, and its base should be where the bone is to be sawn. This will determine the length of the flap, and we should be directed with respect to the breadth of it by the circumference of the limb, for the diameter of a circle being somewhat less than a third of its circumference, although a limb may not be exactly circular, yet by attention to this we may ascertain with sufficient exactness the size of a flap for covering a stump ([Plate IV.] fig. 17). Thus a flap of four inches and a quarter in length will reach completely across a stump whose circumference is twelve inches; but as some allowance must be made for the quantity of skin and muscles that may be saved on the opposite side of the limb, by cutting them in the manner I have directed, and drawing them up before sawing the bone, and as it is a point of importance to leave the limb as long as possible, instead of four inches and a quarter, a limb of this size, when the first incision is managed in this manner, will not require a flap longer than three inches and a quarter, and so in proportion, according to the size of the limb. The flap at its base should be as broad as the breadth of the limb will permit, and should be continued nearly, although not altogether, of the same breadth till within a little of its termination, where it should be rounded off so as to correspond as exactly as may be with the figure of the sore on the back part of the limb. This being marked out, the surgeon, standing on the outside of the limb, should push a straight double-edged knife with a sharp point to the depth of the bone, by entering the point of it at the outside of the base of the intended flap; and carrying the point close to the bone, it must here be pushed through the teguments at the mark on the opposite side. The edge of the knife must now be carried downwards in such a direction as to form the flap, according to the figure marked out; and as it draws toward the end, the edge of it should be somewhat raised from the bone, so as to make the extremity of the flap thinner than the base, by which it will apply with more neatness to the surface of the sore. The flap being supported by an assistant, the teguments and muscles of the other parts of the limb should, by one stroke of the knife, be cut down to the bone, about an inch beneath where the bone is to be sawn; and the muscles being separated to this height from the bone with the point of a knife, the soft parts must all be supported with the leather retractors till the bone is sawn," etc., arteries tied, and dressings applied.[47]

Amputation of Thigh by Rectangular Flap—(Teale's).—I take the opportunity here of describing fully, and as far as possible in his own words, Mr. Teale's method of amputating, this being the situation where his method is most frequently available. The same principle may be applied to amputations at almost any other part of the body.

After advising the surgeon to mark out the proposed line of incision with ink before the operation, he gives the following directions for fixing the exact size of the flap:—"Supposing the amputation to take place ([Plate II.] figs. 9, 10) at the lower part of the middle third of the thigh, the circumference of the limb is to be measured at the point where the bone is to be divided.[48] Assuming this to be sixteen inches, the long flap is to have its length and breadth each equal to half the circumference, namely, eight inches. Two longitudinal lines of this extent are then traced on the limb, and are met at their lower points by a transverse line of the same length. The inner longitudinal line should be first traced in ink as near as practicable to the femoral vessels, without including them within the range of the long flap. The outer longitudinal line, which is somewhat posterior, is next marked eight inches distant from the former and parallel to it. These two lines are then joined by a transverse line of the same extent, which falls upon the upper border of the patella, or upon some lower portion of this bone. The short flap is indicated by a transverse line passing behind the thigh, the length of this flap being one-fourth that of the long one; or, assuming the circumference of the limb to be sixteen inches, and the length of the long flap eight inches, the length of the short flap is two inches. The operator begins by making the two lateral incisions of the long flap through the integuments only. The transverse incision of this flap, supposing it to run along the upper edge of the patella, is made by a free sweep of the knife through the skin and tendinous structures down to the femur. Should the lower transverse line of the flap fall across the middle or lower part of the patella, the transverse incision can extend through the skin only, which must be dissected up as far as the upper border of the patella, at which place the tendinous structures are to be cut direct to the thigh-bone. The flap is completed by cutting the fleshy structures from below upwards close to the bone. The posterior short flap, containing the large vessels and nerves, is made by one sweep of the knife down to the bone, the soft parts being afterwards separated from the bone close to the periosteum, as far upwards as the intended place of sawing.... In adjusting the flaps, the long one is folded over the end of the bone, and brought, by its transverse line, into union with the short flap, the two corresponding free angles of each being first united by suture. One or two additional stitches complete the transverse line of union. Care is now required in arranging the two lateral lines of union. As the long flap is folded upon itself so as to form a kind of pouch for the end of the bone, it is requisite that it should be held in its folded state by a point of suture on each side. Another stitch on each side secures the lateral line of the short flap to the corresponding part of the long one. A longitudinal line of union thus passes at right angles each end of the transverse line."[49]

Mr. Teale's account of the resulting stumps is too long to quote entire, but in a few words, we find that by retraction of the short posterior flap, the cicatrix is drawn up quite behind and out of the way of the bone, that a soft mass without any large nerves or vessels is the result of the partial atrophy of the long flap, and that the patient is able to bear one-half, two-thirds, or even in some cases the entire weight of his body on the face of the stump. Such a power of support is to be found in no other flap except in Mr. Syme's amputation at the ankle-joint.

Spence's Amputation by a long Anterior Flap.[50]—The method used by Mr. Spence in amputations just above the knee-joint obtains the advantages of Teale's method, and avoids many of its disadvantages. He makes two flaps. The anterior one, which is to fall loosely over and cover in the posterior segment of the stump, must have a breadth fully equal to one-half of the circumference of the limb, and must be gently rounded at its extremity, so as to adjust itself readily to the curve of the cut margin of the posterior half of the stump. He begins the anterior incision below, or on a level with, the lower margin of the patella, and when the skin is retracted to a little above the patella, cuts down obliquely to the bone, so as to divide the soft parts up to the base of the flap. For the posterior incision, he begins about two fingers'-breadth below the base of the anterior flap, and the assistant retracting the skin, the edge of the knife is carried obliquely up to the bone (in Alanson's manner) and the posterior soft parts divided, the bone is sawn through—or immediately above—the condyloid portion. Mr. Spence does not advise or practise this method high up. The results are good, for by these means the end of the bone has a thick covering, including muscular fibres, over it, and the cicatrix is not pressed upon in walking. The stump remains full, mobile, and fleshy, as in Mr. Teale's method, without the disadvantage which it has, in requiring the bone to be divided so far above the seat of injury or disease. This is an exceedingly good method of operating in the lower third of the thigh, in muscular patients the very best, and in all cases only equalled in value by Carden's method.