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How to Perform a Transfermoral Amputation (courtesy of emedicine.com)

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Transfemoral amputations

The patient is informed of the surgical risks and complications. All attempts are made to maintain residual extremity length to avoid the necessity of increased energy expenditure. In secondary reconstructive cases, the previous operative report should be reviewed and attention should be directed toward the treatment of the muscles and nerves, which may assist in the exposure and dissection. The extremity is prepared in standard fashion. A tourniquet may not always be feasible, and a sterile tourniquet may be used. A bump is placed under the hip of the involved extremity to assist with rotational control. The previous incisions are identified and used, if appropriate.

Dissection is carried to the muscular layer. The muscles are often retracted and atrophic, necessitating proximal dissection and muscle identification. The adductors, abductors, quadriceps, and hamstrings are isolated in their respective groups. The fascial envelope is maintained for subsequent myoplasty. The neurovascular structures are identified and separately isolated. Separating the nerve from the artery is important. In this manner, pulsatile irritation of the nerve is avoided.

The nerve trunk is mobilized by blunt dissection and distracted and transected at a higher level, allowing retraction into soft tissue surroundings. If a tourniquet has been used, it may be released to evaluate bleeding. The vascular structures are often friable and need to be handled carefully to avoid proximal retraction. The artery and associated veins are separately ligated to avoid arteriovenous connections.

Attention is directed toward the distal residual femur. The periosteum is incised anterior to posterior. Using a 45 angled osteotome, medial and lateral osteoperiosteal flaps are elevated, maintaining their proximal attachments. Elevation of the flaps is aided by rotating the chisel 180, lifting and maintaining the osteoperiosteal attachments. The femur is transected at the level of the osteoperiosteal flaps, with minimal femur necessitating removal. The medial and lateral flaps are sutured together, and circumferential periosteal sutures are placed, occluding the end of the open medullary canal. An alternative method is to prepare a longer medial or lateral based osteoperiosteal flap, securing it to the opposing and circumferential periosteum, achieving medullary coverage.

Myoplasty is performed by suturing the antagonistic muscle groups to each other and anchoring them into the periosteum, covering the osteoplasty. The adductors are sutured to the abductor group first or are anchored to the lateral femoral periosteum. The abductors are imbricated over the adductor attachment and additionally secured to the periosteum anterior and posterior. The flexors are sutured to the extensor group and the underlying adductor/abductor groups, centralizing the distal femur in a muscular envelope.

The skin is fashioned to the underlying myoplasty in a symmetric fashion, avoiding dog-ears and invaginations of the incision. A smooth contour is the goal, allowing for a better limb prosthetic-limb interface. Penrose drains are placed before the closure is completed.

Postoperatively, the residual extremity is placed in an Ace wrap hip spica or a bulky plaster splint, depending on length. Sutures are removed after 2-3 weeks, depending on wound healing. Temporary total-contact end-bearing prosthetic fitting is coordinated with the patient's prosthetist 5-8 weeks postoperatively. Physical therapy is initiated for transfers, desensitization, range of motion, aerobic conditioning, and upper body strengthening.

Postoperative details: Postoperative dressing and treatment vary, each with advantages and disadvantages. Currently, 4 generic types of postoperative dressings are available, as follows:


Soft dressings: These dressings do not control postoperative edema.

Soft dressing with pressure wrap: Soft tissue dressings with compression wrap require even distribution of pressure to avoid possible limb strangulation.

Semirigid dressings: Semirigid dressings include plaster splints and Unna paste bandages held in place with a stockinette. This dressing has the same advantages of a rigid dressing, except no immediate postoperative prosthesis can be used.

Rigid dressings: Many rigid dressings are commercially available, and intraoperative prosthetic assistance may be required. Rigid dressings may have the potential advantage of residual extremity maturation, decreased edema, less pain, wound protection, and early mobilization in combination with an immediate postoperative prosthesis. Disadvantages include poor access to the wound and excessive pressure leading to wound necrosis.
Physical therapy for transfers and assisted ambulation are initiated. Assisted ambulation is at the discretion of the surgeon and therapist, depending on the patient's rehabilitation potential. Precautionary instructions in falling are provided to avoid the potential of injuring and opening the postoperative wound.

A consultation should be obtained for psychosocial and emotional issues. Support groups for people who have undergone amputations and discussion with someone who has undergone amputation are of assistance.
Old 01-04-2005, 10:49 PM Mediocrates is offline  
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