摘要
目的 探究采用股骨近端防旋髓内钉(PFNA)治疗股骨粗隆间骨折时,远端交锁的必要性.方法 南方医科大学解剖教研室提供8对(16例)防腐股骨标本,根据Evans-Jensen分型,将8对股骨左右两侧采用随机数字表法分入两组并制备相应的股骨粗隆间骨折模型,其中稳定组(8例)为顺转子的两部分骨折(Ⅰ/Ⅱ型),不稳定组(8例)为内侧壁不完整骨折(Ⅳ型).分别测量骨折模型在轴向、外展、外旋承重下的刚度值,记录远端交锁与否的刚度值的变化,采用配对样本t检验或符号秩和检验(Wolcoxon检验)进行统计分析.结果 稳定组在轴向承重时,远端交锁时的刚度值小于非交锁[(401.13±121.54)N/m 比(404.75±134.15)N/m,t=-0.596,P＞0.05],差异无统计学意义,而外展和外旋承重时,远端交锁的刚度值大于非交锁[(111.14±52.43)N/m比(108.88±48.35)N/m;(30.92±6.93)N/m 比(29.68±8.09)N/m,t=0.632、1.785,P＞0.05],差异均无统计学意义;不稳定组在轴向、外展承重时,远端交锁的刚度值大于非交锁[(438.97±157.86)N/m 比(420.5947±139.17)N/m,Z=0.700,P＞0.05;(107.25±39.11)N/m 比(105.44±36.81)N/m,t=0.611,P＞0.05],差异无统计学意义,而外旋承重时[(33.76±10.60)N/m比(29.98±13.16)N/m,t=3.186,P＜0.05],差异有统计学意义.结论 从生物力学角度看,当股骨粗隆间骨折为稳定型时,PFNA远端交锁可能不是必须的,但当骨折不稳定时,远端交锁则很有必要.
Abstract
Objective To discuss the necessity of distal locking in the treatment of femoral inter-trochanteric fractures with proximal femoral nail antirotation(PFNA).Methods According to the Evans-Jensen classification,8 pairs of preserved femurs(n=16)were randomly divided into two groups and frac-ture internal fixation models were prepared.A two-part fracture along the trochanter(type Ⅰ/Ⅱ)was made in the stable group(n=8),and an incomplete medial wall fracture(type Ⅳ)was made in the unsta-ble group(n=8).Stiffness values of fracture model under axial,abduction and external rotation load were measured respectively,and the change of stiffness value with or without distal locking was recorded.Paired sample t-test or Wolcoxon test was used for statistical analysis.Results In stable group,the stiffness val-ue with distal locking was lower than that without locking under axial force,and the difference was not sta-tistically significant[(401.13±121.54)N/m vs.(404.75±134.15)N/m,t=-0.596,P＞0.05].The stiffness with distal locking was higher than that without locking under abduction and external rotation,and the difference was not statistically significant[(111.14±52.43)N/m vs.(108.88±48.35)N/m;(30.92±6.93)N/m vs.(29.68±8.09)N/m,t=0.632,1.785,P＞0.05].In unstable group,the stiff-ness with distal locking was higher than that without locking under axial and abduction forces,and the differ-ence was not statistically significant[(438.97±157.86)N/m vs.(420.5947±139.17)N/m,Z=0.700,P＞0.05;(107.25±39.11)N/m vs.(105.44±36.81)N/m,t=0.611,P＞0.05],while in external rota-tion,the difference was statistically significant[(33.76±10.60)N/m vs.(29.98±13.16)N/m,t=3.186,P＜0.05].Conclusion From a biomechanical point of view,PFNA distal locking may not be necessary when the intertrochanteric fracture is stable,but it is necessary when the fracture is unstable.
基金项目
广州中医药大学第三附属医院创新基金(SY2019009)
NETL
NSTL
万方数据