Femur lengthening with a telescopic ISKD nail – long-term clinical and radiological results

Introduction. Among various modern systems of limb lengthening, lengthening with an intramedullary nail seems to be most modern and comfortable for the patient. The aim of this study was to evaluate the femur lengthening with a self-distracting intramedullary skeletal kinetic distractor (ISKD). Material and methods. This is a retrospective study, conducted in one hospital and involved 10 patients with a mean age of 15.9 years. All patients underwent femur lengthening with an ISKD nail. The mean follow-up period was 38.7 months. We evaluated: gained length; treatment duration; healing index; problems, obstacles and complications during treatment; and the final result. At the last visit, we assessed the condition of the knee joint and daily performance. Results. Mean femur lengthening was 5.7 cm. Mean treatment duration was 7.8 months and mean distraction index was 1.4 months/cm. The main problems and obstacles were related to the initial nail distraction, occurring in 5 patients: ineffective distraction occurred in 4 of the patients and distraction was too rapid in 1 patient. Delayed union was observed in 1 patient. The most common problems reported by the patients were: limping, different thigh circumference, slight difficulties with squatting, and occasional knee pain during great effort accompanied by the feeling of instability. Conclusions. Intramedullary nail lengthening seems an effective method of limb equalization in teenagers and young adults, although patients should be warned that distraction with an intramedullary nail would not result in achieving perfect limb function.