SEVERE TIBIAL GROWTH-RETARDATION IN TOTAL FIBULAR HEMIMELIA AFTER LIMB LENGTHENING

Seven patients with total fibular hemimelia who underwent limb-lengthe ning procedures prior to skeletal maturity were evaluated for tibial a nd femoral growth after lengthening. The average preoperative follow-u p was 6.5 years and all patients were followed to skeletal maturity. T hirteen segments (eight tibiae and live femora) were lengthened by thr ee methods (Wagner, Ilizarov, and modified Ilizarov). The average preo perative limb-length discrepancy was 9.7 cm, and the average projected limb-length discrepancy at skeletal maturity was 12.5 cm. The average tibial lengthening was 6.7 cm (range, 5.3-10) with an average percent age of lengthening of 26% (range, 19-40%). The average postoperative g rowth rate of the tibia was 80% (range, 70-100%) and of the femur, 83% (range, 70-90%) of the normal side. Five tibial showed a decrease in the average preoperative growth rate from 82.5% (range, 70-100%) to 39 % (range, 26-54%) of the normal side. Two tibiae had no longitudinal g rowth after lengthening. The average postoperative growth rate of the femur decreased from 83% (range, 70-90%) to 61% (range, 26-125%). In o ne patient there was an increase in the rate of growth of the femur. T hese findings suggest that limb lengthening in skeletally immature chi ldren with total fibular hemimelia results in severe growth retardatio n of the tibia after lengthening. The subsequent growth of the tibia a fter lengthening in patients with total fibular hemimelia is unpredict able.