Can flexible intramedullary nails provide proper fixation of long bone fractures in patients weighing over 100 pounds?

Length stable diaphyseal femur and tibial shaft fractures in paediatric patients may be fixed with flexible intramedullary nails (FINs) in selected paediatric patients. Previous studies based on biomechanical models have suggested that the forces of gait may overcome the stability of this construct in patients weighing more than 45 kg. Surgeons occasionally use FINs for fixation in patients outside this limit. The purpose of this study was to evaluate whether FINs could be used in paediatric patients weighing over 45 kg without increasing the rate of complications. A retrospective cohort review was performed for 12 patients weighing over 45 kg with femoral or tibial fractures treated with FINs, matched 1:2 for gender and bone type with 24 patients weighing less than 45 kg; also with femoral or tibial fractures treated with FINs over the same period. There was no significant differences in rate of major complication or increases in angulation between the study and control group. The study group had major complication (8.3%) of hypertrophic nonunion in the tibia, and the control group had one major complication (4.2%) of increased anterior bowing in the femur. The odds ratio of developing a major complication in the study group was 2:1 which was not significant (p = 0.06). FINs can be considered as a treatment option for fixation of femoral and tibial fractures in a select group of paediatric patients weighing more than 45 kg. Clinical and functional outcomes measurements in larger sample sizes are needed before making any definitive conclusions. 在選定的兒科患者中，可以使用彈性髓內釘（FINs）固定長度穩定的股骨和脛骨骨幹骨折。基於過往生物力學模型的研究表明，在體重超過45公斤的患者中，步態應力可能會克服這種結構的穩定性。 外科醫生偶爾會使用FINs來固定超出此限制的患者。 本研究的目的是評估FINs是否可用於體重超過45 公斤的兒科患者，而不會增加併發症的發生率。 對12名體重超過45 公斤的患者進行了回顧性隊列評估，其中股骨或脛骨骨折採用FINs治療； 與同時期24名體重低於45公斤的患者使用FINs治療股骨或脛骨骨折，以性別和骨骼類型匹配，比率為1：2。 研究組和對照組之間主要併發症的發生率或成角增加無顯著差異。 研究組有脛骨肥大性骨不連的主要併發症（8.3%），對照組有一個主要併發症（股骨前弓增加4.2%）。研究組發生主要併發症的比值比為不顯著的2：1（p = 0.06）。 在選定的體重超過45公斤的兒科患者中，FINs可被視為固定股骨和脛骨骨折的治療選擇。 在做出任何明確的結論之前，需要更大樣本量的臨床和功能結果測量。