CHAPTER 148: AMPUTATION, SUPRACONDYLAR

INDICATIONS

Common indications for supracondylar amputation include trauma, poor blood supply, tumor, and progressive untreatable. Amputation should not be performed unless all conservative measures have failed.

The amputation at the level of the thigh is described in detail here. This is a frequent site following failure of reconstructive or bypass arterial procedures or in the presence of unreconstructable circumstances as documented with proximal and distal arteriography.

PREOPERATIVE PREPARATION

The preoperative preparation must of necessity vary with the indications for amputation as outlined in the preceding section. Careful evaluation must be made to determine whether there is a localized arterial obstruction, and arteriography is essential. If localized obstruction is present, a proximal (e.g., an iliac stent or aortofemoral) reconstructive procedure may restore an adequate blood inflow, or a distal (e.g., femoropopliteal) bypass arterial graft may eliminate the need for amputation.

When infection is present, aggressive surgical debridement is the most critical step for success. Appropriate antibiotic regimens should be tailored based on documented sensitivities. Should there be a localized skin infection at the proposed level of amputation, the procedure is delayed if improvement is possible. In the presence of an advancing infection a guillotine or open amputation is done above the level of infection, with a subsequent definitive amputation at a higher point a few days later or when sepsis has cleared.

For elective amputations, preoperative consultation with physical therapy and a prosthetist can help the patient be emotionally and physically ready for the rehabilitation required after amputation surgery.

ANESTHESIA

Low spinal anesthesia is used most frequently, although inhalation anesthesia may be administered unless the patient’s condition contraindicates it.

POSITION

The patient is placed with the hip on the affected side out to the margin of the table to allow full abduction of the thigh by an assistant, and the calf or ankle may be elevated with several sterile towels. The hair is clipped at the operative level.

OPERATIVE PREPARATION

The skin from the lower abdomen to well below the knee is prepped. A sterile sheet is placed beneath the thigh. The foot and lower leg up to the knee are covered with an impervious stockinette (figure 1). Unless there is evidence of progressive infection, the extremity is elevated by the assistant to encourage venous drainage. If a low amputation is planned, a sterile tourniquet can be applied high on the thigh.

INCISION AND EXPOSURE

The type of flap that is used varies. With progressive infection of the lower leg, a circular incision is made for a guillotine amputation. However, when possible, anterior and posterior flaps are outlined with a sterile marking pen, ensuring an appropriate stump length (figure 1). ...