Abstract
Background
Lengthening over nail (LON) and the use of internal lengthening nails have been developed to minimize patients' time in a frame during femur lengthening. This study compares the outcomes of two techniques of femur lengthening, LON and Intramedullary Skeletal Kinetic Distraction (ISKD).
Methods
In this retrospective study, 12 consecutive ISKD procedures were performed for femoral lengthening and followed for an average of 76 months. After the ISKD group, 20 consecutive femoral lengthening procedures were performed as an LON technique and followed for an average of 27 months.
Results
There was no significant difference in achieving the lengthening goals between the two procedures. The healing index for the LON group averaged 1.4 months/cm, while the ISKD group was 3.2 months/cm (p=0.242). The distraction rates for the ISKD had a fast group (>1mm/day) with an average distraction rate of 1.7 mm/day and a slow group (<1mm/day) with a distraction rate of 0.84 mm/day. The LON group had an average distraction rate of 0.88 mm/day (p<0.001). The incidence of complications that required further unanticipated surgeries for the LON group was 1/20 (5%), while the ISKD group had complications in 6/12 femurs (50%, p=0.004).
Conclusions
We concluded that the LON technique is a more predictable and reliable method for femoral lengthening than the ISKD.