Townsend Courtney M.Jr., Evers B. Mark. Atlas of General Surgical Techniques: Expert Consult

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STEP 1: SURGICAL ANATOMY

◆ A comprehensive understanding of the anatomy of the thigh and knowledge of the pre-

existing level of circulation is critical before undertaking amputation of the leg.

◆ Figure 94-1 demonstrates key anatomic structures that must be considered with supracon-

dylar amputation, including the relationship of the femur with the surrounding vessels.

STEP 2: PREOPERATIVE CONSIDERATIONS

◆ Select the level of amputation that will optimize healing and preserve as much function as

possible.

◆ The indications for supracondylar amputations include the following:

◆ Nonambulatory, debilitated patient with indication for amputation with high risk for

developing ﬂ exion contracture of the knee after below-knee amputation.

◆ Debilitated patients with knee joint contracture and/or nonviable calf muscle or skin for

creation of the below-knee ﬂ ap.

◆ Failure of a bypass graft.

◆ Failure of below-knee amputation.

◆ Severe ischemia, necrosis, infection, joint contractures, neoplasm, trauma, and crush in-

juries involving the calf or distal thigh may preclude performing below-knee amputation.

◆ A vascular study should be obtained to determine whether below-knee amputation can be

attempted.

◆ Objective evidence that the selected level is one at which primary healing is likely to occur

should be established.

◆ The most common level for supracondylar amputation is at the midfemur. Objective

evidence that the selected level is one at which primary healing is likely to occur should be

established.

◆ Preservation of the length of the femur results in better function.

CHAPTER

Supracondylar Amputation

Jong O. Lee

CHAPTER 94 • Supracondylar Amputation 1043

Division of femoral vessels

with sciatic nerve identified

and divided under traction

Periosteum and surrounding

tissue cleared from bone

FIGURE 94 –1

1044 Section XIII • Amputations

STEP 3: OPERATIVE STEPS

1. INCISION

◆ Proper positioning of the patient is supine. A roll can be placed under the thigh to position

the leg.

◆ The incision must be carefully planned to allow optimal skin ﬂ ap for closure. The ﬁ sh-

mouth–shaped incision is made using equal length posterior and anterior ﬂ aps. The corners

of the ﬁ sh-mouth incision should be at the level of the amputation of the femur. The length

of the ﬂ aps should be approximately two thirds of the diameter of the thigh at that level

(Figure 94-2).

◆ The length of the ﬂ aps should be sufﬁ cient to provide secure, tension-free closure over the

femoral stump.

◆ The skin incision is made and extended through the subcutaneous tissue and the fascia

over the underlying muscle at the same level of the skin incision. The muscles are divided

using electrocautery at least 5 cm distal to the intended site of femur amputation and are

allowed to retract.

◆ The anterior femoral muscles are divided ﬁ rst followed by the medial femoral muscles. The

posterior femoral muscles are divided last.

◆ A clamp can be used under the muscles to retract them and place them under traction.

◆ The muscle ﬂ aps should be longer if myodesis/myoplasty is planned.

2. DISSECTION

◆ As muscles are divided, the nerves and vessels are identiﬁ ed.

◆ The femoral artery and vein are found deep in the anterior medial thigh, lying adjacent to

the femur.

◆ The femoral artery and vein are isolated, double clamped, suture ligated, and divided

(see Figure 94-1).

◆ The sciatic nerve is identiﬁ ed between the adductor magnus and biceps femoris muscles.

The nerve is placed on a gentle traction, ligated proximately, sharply divided, and al-

lowed to retract.

◆ The sciatic nerve contains relatively large arteries and therefore should be ligated.

CHAPTER 94 • Supracondylar Amputation 1045

Fish-mouth incision of

skin and deep tissue

Level of division of femur

FIGURE 94 –2

1046 Section XIII • Amputations

◆ The femur is divided using a saw.

◆ After anterior muscles are divided, the periosteum of the femur is incised circumferen-

tially and is cleared approximately 2 cm distally. The femur is divided immediately distal

to the periosteal incision.

◆ The level of the femur resection is identiﬁ ed by cutting the periosteum, but periosteum

should not be stripped from the femur. Stripping periosteum from the femur may result

in loss of blood supply to the exposed bone.

◆ The femur is divided at least 3 to 5 cm proximal to the line of skin incision.

◆ The edges of the bone should be rasped to form a smooth contour.

◆ Divided muscles are retracted superiorly for better exposure during resection

(Figure 94-3).

◆ An oscillating power saw or Gigli saw is used to divide the femur (see Figure 94-3).

3. MYODESIS/MYOPLASTY

◆ A long quadriceps ﬂ ap with its fascia can be sutured to the posterior fascia and major

muscle groups.

◆ Several small holes (

⁄64 inch) are placed through the cortex of the distal end of the femur

⁄8 inch from the distal cut end of the femur. Loop mattress sutures are placed through the

major muscle groups and drawn through the holes.

◆ The adductor and hamstring muscles are sutured to and across the end of the femur

through the drill holes. The femur is kept in adduction as the adductors are tied down.

◆ The femur should be in full extension as the quadriceps are secured to avoid hip ﬂ exion

contracture.

◆ Myodesis or myoplasty is performed in a nonischemic limb. It is avoided in ischemic limbs

because of increased risk of wound breakdown.

◆ If myodesis is planned, the posterior muscle ﬂ aps are left 2 inches longer than the level

of bony transection. If both myodesis and myoplasty are planned, all muscle groups are

left long.

CHAPTER 94 • Supracondylar Amputation 1047

Division of femur

Soft tissue protected

by retractors

Gigli saw

Saphenous vein

ligated and divided

FIGURE 94 –3

1048 Section XIII • Amputations

4. CLOSING

◆ The wound is irrigated. Once hemostasis is achieved, closure is performed by ﬁ rst approxi-

mating the fascias of the anterior and posterior ﬂ aps using interrupted 2-0 Vicryl sutures

(Figure 94-4).

◆ If there is persistent oozing, a drain is placed.

◆ The skin edges of the two ﬂ aps are approximated with 3-0 nylon sutures in interrupted

fashion or with staples (Figure 94-5), which are left in for 3 weeks.

◆ After soft dressings are applied, splints may be applied. To prevent ﬂ exion contracture of

the hip, pillows are not used for support.

Fascia and muscle are

approximated with tension

relieved by external compression

FIGURE 94–4

CHAPTER 94 • Supracondylar Amputation 1049

Skin closure with surgical

staples or sutures

FIGURE 94–5

1050 Section XIII • Amputations

STEP 4: POSTOPERATIVE CARE

◆ Complications include hematoma, infection, wound necrosis, and contractures.

◆ A drain may be used if there is persistent oozing.

◆ One of the most immediate postoperative complications can be wound hematoma, which

occurs in a small percentage of patients.

◆ Small hematomas can be observed.

◆ Large hematomas may need to be drained.

STEP 5: PEARLS AND PITFALLS

◆ It is imperative to handle tissues gently and attain absolute hemostasis.

◆ Guillotine amputation is used in infected leg or sepsis.

◆ A tourniquet can be used in nonischemic limbs.

◆ A tourniquet is not used in ischemic limbs.

SELECTED REFERENCES

1. Fisher DF: Lower extremity amputations. In Baker RJ, Fischer JE (eds): Mastery of Surgery, 4th ed.

Philadelphia, Lippincott Williams & Wilkins, 2001, pp 2191-2198.

2. Carnesale PG: Amputations of lower extremity. In Carnale ST (ed): Campbell’s Operative Orthopaedics,

10th ed. Philadelphia, Mosby, 2002, pp 575-586.

3. Anderson KM: Knee disarticulation and above-knee amputation. Oper Tech Gen Surg 2005;7:90-95.

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INTRODUCTION

◆ Transmetatarsal amputation may be indicated for ischemic tissue loss and/or infection of the

great toe or several toes. Infection that extends proximal to the metatarsophalangeal crease

or involving the deep tissues of the foot will likely need a higher level of amputation.

STEP 1: SURGICAL ANATOMY

◆ The pertinent anatomy of the foot and lower leg is illustrated in Figure 95-1.

CHAPTER

Transmetatarsal Amputation

Michael D. Trahan

Line of skin incision

with acute angle laterally

Line of divison of

metatarsal at midshaft

FIGURE 95 –1