Weinstein Lovell and Winters Pediatric Orthopaedics 7e

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CHAPTER 30  |  The Child with a Limb Deficiency

If the deformity was present in the lateral femoral condyle, they suggested temporary ­stapling of the medial femoral con- dyle, since osteotomy has a very high recurrence rate unless performed near the end of growth. The authors’ experience indicates that it is not as simple as this and that the recurring nature of the valgus following good correction of alignment suggests other causes of this problem. Ankle Reconstruction.  Any attempt to save the limb of a child with significant fibular deficiency will require efforts to realign and stabilize the ankle. There is renewed interest in this subject with attempts to lengthen the leg. The Gruca procedure is designed to provide lateral stabil- ity to the foot in the absence of the fibula. Serafin gives the first report of the technique in the English literature and recounts the various attempts at bone grafting and other procedures that were described before Gruca developed his technique (118). In the Gruca procedure the tibia is split longitudinally. The medial segment is displaced proximally with the talus, leaving the lateral fragment as a lateral buttress. Thomas and Williams describe the early results in nine patients treated with this procedure. The follow-up is short and the evaluation of function incomplete (119). More recently, a newer proce- dure was described to provide lateral stability that involves transplantation of a tricortical iliac crest graft with apophysis and gluteal fascia to the lateral distal tibia (120). Neither sur- gery has been widely used and would seem to have little to recommend it. Arthrodesis of the talus to the distal tibia is a logical plan in conjunction with leg lengthening, but there are no reports on its outcome. It is likely that this would also require release of all of the tendons crossing the ankle joint to prevent foot deformity. Drift of the foot through the physis or the fusion itself with lengthening and over time seems a possibil- ity. There are also case reports of tibial lengthening with an extra-articular screw from the calcaneus to the tibia to prevent progressive equinus (121). Neither technique can be recom- mended at this time. The ball-and-socket ankle joint, seen in the Kalamchi type IA deficiencies, usually require no treatment. The authors have, however, seen several children with increasing valgus during adolescence or following leg lengthening who become symptomatic with normal athletic activity. They have been successfully treated by a distal tibia varus angular osteotomy. Prosthetic Management.  Prosthetic management of the fibular- deficient limb is different than management of a Syme ampu- tation in an adult after trauma. In the child, the prosthesis is designed to accommodate growth and to help stabilize knee laxity and hyperextension through socket design and align- ment. Emphasis is placed on socket alignment and minimizing rotational forces acting on the knee. The socket fitting for a Syme or Boyd amputation may be designed to bear all of the weight on the end of the resid- ual limb, as intended, on the patellar tendon and flare of the proximal tibial condyles, as in a transtibial amputation, Text continued on page 1552

FIGURE 30-14.  It is not necessary to remove the cartilage from the distal tibia or to cut any bone from the distal tibia. Closure is accomplished by suturing the deep layer of the heel pad to the deep fascia and periosteal tissue of the proximal part of the dorsal incision. This will anchor the heel pad. Fixation pins are not neces- sary and are largely ineffective because posterior migration of the heel pad occurs late as a result of the imbalance of forces created by the failure to section completely all tendons pulling on it. It is wise to deflate the tourniquet before closure in order to check the circulation to the flaps and to control the bleeding. Drains do not appear to be necessary. (Fig. 30-19A–E). When correction of the bow is necessary in older children who are already in their prosthesis, several ­fixation options, including crossed Steinman pins, plates, or intramedullary devices are available. Correction of Genu Valgum.  Development of progressive genu valgum has long been known as a complication of fibular defi- ciency. It is one of the major problems seen in the gait of chil- dren with this problem. At first, it is merely cosmetic and can be accommodated with prosthetic alterations. However, if it becomes more severe, it will increase the forces on the lateral compartment and make good alignment impossible. Westin et al. noted that the tibia often developed an ante- rior flexion along with the valgus, and attributed the ­problem to an abnormality in growth in the lateral and ­posterior ­portions of the proximal tibial physis (36). This problem is different from anterior bow in the diaphysis of the tibia. Most recently, Boakes et al. (82) documented a decrease in the height of the lateral femoral condyle that was not present prior to walking. There was a suggested relation between the extent of anteromedial bowing of the tibia and the subsequent decrease in height of the lateral femoral condyle. They sug- gested that tibial osteotomy might prevent the changes in the lateral femoral condyle and correct the anteromedial ­bowing.