Two Techniques for Retrograde Flexible Intramedullary Fixation of Pediatric Femur Fractures: All-Lateral Entry Versus Medial and Lateral Entry Point.

BACKGROUND: Multiple techniques for flexible intramedullary nailing (FIMN) of pediatric femur fractures have been described. To our knowledge, no study has compared combined medial-lateral (ML) entry versus all-lateral (AL) entry retrograde nailing. This study compares surgical outcomes, radiographic outcomes, and complication rates between these 2 techniques.

METHODS: A retrospective review of a consecutive series of patients treated by retrograde, dual FIMN of femur fractures was performed from 2005 to 2012. Demographics and operative data were recorded. Radiographs were analyzed for fracture pattern, fracture location, percent canal fill by the nails, as well as shortening and angulation at the time of osseous union. Rates of symptomatic implants and their removal were noted. Data were compared between patients treated with medial and lateral entry (ML group) nailing and those treated with all-lateral entry (AL group) nailing using the Student t test and correlation statistics.

RESULTS: Of the 244 children with femoral shaft fractures treated with retrograde FIMN using Ender stainless steel nails, 156 were in the ML group and 88 were in the AL group. There were no statistical differences in sex (74% vs. 82% males), age (8.0 vs. 8.6 y), weight (29.4 vs. 31.1 kg), or fracture pattern between the 2 groups. The average total anesthesia time was less in the AL group (133 vs. 103 min) (P<0.0001). There was no difference between the techniques in shortening (3.9 vs. 3.0 mm), coronal angulation (2.9 vs. 2.6 degrees), or sagittal angulation (3.3 vs. 2.7 degrees) at union. In the AL group, there was a correlation between canal fill and reduced shortening at union. No differences were found in the presence or degree of varus alignment, procurvatum deformity, or recurvatum angulation between the constructs. There were 5 malunions in the AL group and 9 malunions in the ML group (5.7% vs. 5.8%, P=1). The incidence of having a healed femur fracture with >10 degrees of valgus was higher in the AL group (0% vs. 3.4%) (P=0.04). There were no differences between the groups in the rate of symptomatic implant removal or surgical complications.

CONCLUSIONS: The AL entry technique for FIMN of pediatric femur fractures is 30 minutes faster without worse final fracture alignment, additional complications, or increased rates of symptomatic implants. When using the AL technique, specific attention should be paid to percentage of canal fill and ensuring that the fracture is not reduced in a valgus position.

LEVEL OF EVIDENCE: Level III-therapeutic.