Lower Limb Skin Coverage Problems And Prosthetic Adaptations
Gael R. Frank, M.D. Ralph E. Payne, Jr., M.D.
As children grow older they are increasingly exposed to the possibility of accidents which may lead to traumatic amputation. These amputations are of infinite variety and frequently create problems related to bone growth, skin coverage, and blood or nerve supply to the amputation stump. The skin deficiencies of these stumps often present special problems in prosthetic fitting. This is especially true in the lower extremities where limbs which sometimes have only a borderline capacity to tolerate repeated trauma are subjected to the insult of weight bearing.
Increase in Skin Coverage Problems
Since modern machine age trauma presents a wide range of amputation possibilities, each case must be evaluated on its own merits. Several unusual cases encountered in our clinic recently illustrate problems in obtaining satisfactory skin coverage and in adapting the prosthetic prescription to the surgical end product.
Our attempts to solve these problems may be of Interest to others since an increasing incidence of similar problems can be anticipated in the future, for the following reasons:
Increased knowledge of vascular surgery techniques will produce more amputation stumps with severely traumatized residuals. Formerly these stumps would simply have been amputated at a higher level, but now are salvaged. They provide a challenging problem to the clinic team and a severe handicap to the patient unless solutions can be found. The circulation to these stumps may be derived from an arterial graft, or from an artery imbedded in scar tissue. In such cases, extreme care must be exercised to assure that the prosthesis does not cause further trauma by exerting pressure along the course of the artery.
Better initial soft tissue management in trauma cases will result in longer amputation stumps which, however, may require revision for various reasons. In some it may be desirable to replace split thickness skin graft coverage by pedicle flap skin grafts when it is of advantage to maintain the length for prosthetic fitting or to save a growth center.
Reimplantation of amputated limbs is now becoming popular. It can be anticipated that the terminal portions of some of the salvaged limbs will prove to be less than satisfactory. When amputation of a peripheral segment becomes necessary following partially successful reimplantation, some unique problems will be presented to the amputating surgeon, as well as to the prosthetic team called upon to fit a stump with borderline sensation or circulation. It will be necessary to determine which traumatic hemipelvectomy should be reimplanted to save an ischium at least, or possibly to salvage an above-knee stump; and which traumatic above-knee amputations should be reimplanted to save a knee and leg. Repair of the cutaneous sensory nerves and adequate blood supply will share equal importance with motor return. Most certainly the more favorable results will be obtained in younger children and herein lies the challenge to be prepared, for the problem will not be encountered too frequently.
The continued development and refinement of prosthetic devices and techniques will make it possible to fit amputation stumps which formerly would have needed major revisions or which could not have been fitted at all.
The following three cases were selected to illustrate solutions to unique skin coverage problems and prosthetic adaptations to the resulting stump.
Case #1: D.M.
At age eight the patient sustained an amputation of both lower extremities in a railroad accident. One lower limb was amputated at a high thigh level and the other was disarticulated through the knee. He received his initial care elsewhere and was referred to our clinic seven months later.
Examination revealed that there was complete skin coverage on the side of the knee disarticulation, but that most of the skin over the distal five inches of the stump was too thin to permit any attempt at prosthetic fitting (Fig. 1 ).
We felt that an attempt to save the distal femoral epiphysis was justified in view of the very short above-knee stump on the opposite side. A large pedicle graft was raised from the chest and abdomen in stages (Fig. 2A and B ) and transferred to the end of the stump.
The prosthesis now worn on the knee-disarticulation side consists of an open type, quadrilateral, knee-bearing socket with laced opening to accommodate the enlarged condyles, outside knees, and SACH foot. The above-knee stump is fitted with a conventional wood quadrilateral socket. Suspension is by a bilateral hip control belt (Fig. 5A and Fig. 5B ). When growth ceases the knee disarticulation stump will be revised to remove the patella and shape the condyles.
Case #2; A.W.
At age twelve, this white female sustained a compound fracture of the femur in an auto accident. The artery was severely contused and a periarterial sympathectomy was performed by "stripping the artery". The fractured left femur was fixed with an intermedullary rod and an extensive laceration on the left foot was debrided and closed. The circulation to the foot and leg was never entirely satisfactory and gangrene developed necessitating a Guillotine below-knee amputation on the tenth post injury day. Skin traction was applied but it was not possible to obtain skin closure. When the patient was referred to us two months post injury, the skin edges had retracted and the dead bone ends were projecting far beyond the confines of the soft tissues (Fig. 6 ).
A.W. also had open granulating wounds in the thigh, laterally as a result of the trauma and medially along the incision made to explore the femoral artery. In this particular case there would have been no advantage in covering the below-elbow stump since it was too short for prosthetic fitting and the bone ends were necrotic. Since the growth potential in the distal femur was insignificant (Fig. 7 ), a supracondylar amputation was performed. The granulating wounds in the thigh were covered with split skin. After closure of all wounds was complete, the larger scars were excised and more desirable scars obtained. The final result is shown in Fig. 8A and Fig. 8B .
A total contact plastic socket with outside knee joints and SACH foot was fitted. Even with the total contact socket, she occasionally had areas of skin breakdown in the stump. However by limited initial use of the prosthesis, the skin adapted to the pressures and she has had no difficulty recently.
Case #3: W.W.
Both extremities of this adult white male were amputated by a train. In order to obtain satisfactory skin closure it was necessary to amputate through the subtrochanteric area bilaterally. He was referred to our clinic four months following the injury with skin coverage as illustrated in Fig. 9 .
The area of split skin coverage on the left just anterior to the long skin flap (arrow) is in a non-weight-bearing area. Discussion of a prosthesis with this man revealed that his first goal was sitting stability. Amputation was a secondary consideration. He was prescribed a modified Canadian hip-disarticulation prosthesis consisting of a large bucket seat, well padded in the weight bearing areas, with a single prosthetic limb utilizing primarily the hinging and alignment of the standard Canadian hip-disarticulation prosthesis. This limb was constructed shorter than normal and aligned in adduction to assist balance. The prosthesis accomplished the primary goal of giving sitting stability (Fig. 10 ).
It also provided a means of locomotion with crutches (Fig. 11 ). He was able to master the use of this prosthesis in about one month with twenty-five sessions in Physical Therapy. It was necessary to teach him to fall without injuring himself and to get from the floor to a standing position without help. In addition he obtained an added psychological boost by being able to stand at a height somewhat comparable to his associates.
Three case reports selected from our Amputee Clinic to illustrate problems relative to skin closure in amputation stumps in the lower limbs following trauma have been presented. We feel that problems such as these will be seen with increasing frequency in the future. Better initial care of the trauma victim will salvage some longer amputation stumps with inherent problems requiring adaptations for prosthesis wear. Formerly, these stumps would probably have been amputated at a higher level. As the attempts at reimplantation of amputated limbs increase, there will be an increasing number of amputations of non-viable or non-functional terminal segments of these limbs. The remaining stump will undoubtedly have a diminished circulation, and the skin sensation will likewise be compromised.
Each case presents its own unique problems and must be judged on its own merits. The prosthetic team should avoid any tendency to stereotype the management of these patients, but should draw from the ever increasing storehouse of surgical and prosthetic techniques.
Gael Frank is an Assistant Professor and Ralph Payne is a Clinical Assistant at the Department of Orthopaedic Surgery University Medical Center, Oklahoma City, Oklahoma