Leg Length Discrepancy and Angular Deformity after Flexible Intramedullary Nail fixation in Pediatric Femoral Shaft Fractures

Abstract

Objective Femoral fracture is one of the most frequent fractures in children and complications occurs such as malunion and leg length discrepancy after internal fixation using flexible intramedullary nail. The author intended to consider operational treatment using flexible intramedullary nailing through a quantitative data including age, pattern and location of fracture for angulation, and leg length discrepancy. Methods A retrospective survey was performed by 30 cases of child patients who underwent internal fixation using flexible intramedullary nail for femoral shaft fracture. Using a simple radiography, duration of union and angulation were measured. Leg length discrepancy was evaluated by scanogram. By measuring each 2 times at an interval of 1 week by 2 observers, error among observers and error in observer were excluded. For statistical validation, t-test and lineal regression analysis were used. Results Immediate postoperatively, valgus condition of 7 degrees was represented and affected side was represented to show varus of 5.6 degrees on average in 46.6% of child patients. The more age of patient is young, more angulation was represented to be significantly taken place in transverse fracture rather than oblique fracture, but depending on fracture location, significant difference was not observed. Leg length discrepancy showed overgrowth of 6.39 mm on average. And cases of overgrowth over 5 mm being were represented and age of all the child patients was below 9 years old. As a result of statistical analysis, it was observed that the age is younger, leg length discrepancy was prone to be occurred, and its significant relevance with fracture form or fracture location was not represented. Conclusion Transverse fracture is represented at the time of performing internal fixation using flexible intramedullary nail. Occurrence rate of angulation and leg length discrepancy was high but follow-up period is required to be extended even after the time when growth is completed on a long-term basis and in case of imperfect correction, additional treatment such as physeal plate stapling is required. Bone shortening and lengthening may be required and it is considered to be a useful method for femoral shaft fracture of children. Key words: Femoral fractures; Fracture fixation; Intramedullary nailing; Leg length inequality; Lower limb deformity