Sections of bone in Pirogoff’s amputation and its modifications: 1, oblique section of calcaneum to correspond with (1) oblique section of tibia. (Gunther.) 2, curvilinear or concave section of calcaneum to correspond with (2) convex section of tibia. (v. Bruns.) 3″, horizontal section of calcaneum to correspond with (3) similar section of tibia. (Pasquier Le Fort.) 3‴, vertical section of calcaneum to correspond with (3) horizontal section of tibia. (Typical Pirogoff.) (Modified by Matas from Mignon.)
Fig. 707
Osteoplastic excision of foot. (Mikulicz.)
Let us, then, consider but one or two amputations of the leg—that low down or near the middle and that at the knee. Whatever the method it is most desirable that the scar be kept off to the side, and especially away from the front of the shin. This can be best accomplished by a modified circular ([Fig. 708]) or a bilateral flap method ([Fig. 711]), or by the oblique method with lateral incisions, which practically convert it into an anteroposterior operation, while for certain instances the method of Teale may be preferred, i. e., that with a long anterior and short posterior flap, or its modification by which the flaps are made more lateral, or the even long flap method of Bell.
Fig. 708
Modified circular amputation of upper third of leg. (Erichsen.)
Whichever of these be selected, after division of the muscles and exposure of the bone, it is usually helpful to retract the flaps, whatever their shape, by a cloth retractor made of a piece of sterile bandage torn into three strips, the middle of which should be inserted between the bones of the leg, the interosseous membrane being divided for this purpose; by this they are held more perfectly out of the way during the act of dividing the bones. The anterior border of the tibia, which is practically a sharp ridge, should be divided obliquely (bevelled), either by a small oblique section before the transverse division is made, or by effecting this later, in order that there shall not remain a sharp point to project through the skin or be subject to constant irritation. The tibia is usually divided transversely, with the above exception. The fibula may be divided slightly obliquely. It is customary, however, to make the division simultaneously, and to so conduct the sawing process as to divide the fibula completely before the last strokes of the saw cut through the tibia.
There is greater difficulty in the recognition and securing of vessels in leg amputations than in any other, especially if they have been divided obliquely. The principal vessels may be found from their known anatomical location. They nevertheless sometimes tend to retract and they must be followed up in order to properly secure them. The accompanying nerve trunks should also be seized firmly, drawn down, and divided two or three inches above the line of division of the other tissues, in order that they may retract out of harm’s way. Every nerve which can be recognized, even in the skin, should be thus treated. Before closing the wound it is well, unless one is absolutely sure of his work, to release the tourniquet and ascertain if any vessel which would otherwise bleed be not yet secured. Oozing may be checked with hot water, while muscle surfaces which leak too much blood may be lightly enclosed within catgut sutures inserted with a curved needle.