University of Tennessee, College of Medicine Chattanooga, Department of Orthopaedics, 975 East Third Street, Hospital Box 287, Chattanooga, TN 37403, USA.
Injury. 2012 Jun;43(6):802-6. doi: 10.1016/j.injury.2011.09.012. Epub 2011 Oct 21.
The purpose of this study is to determine the biomechanical stability of a novel prototype femoral neck locking plate (FNLP) for treatment of Pauwels type C femoral neck fractures compared with other current fixation methods.
Forty femur sawbones were divided into groups and a vertical femoral neck fracture was made. Each group was repaired with one of the following: (CS) three parallel cancellous screws; (XCS) two cancellous lag screws into the head and one transverse lag screw into the calcar; and (FNLP) a novel FNLP with two 5.7 mm locking, one lag screw into the calcar and two screws into the shaft; and (AMBI) a two-hole, 135° AMBI plate with a derotation screw. All groups were tested for change in axial stiffness over 20000 cycles, and rotational stiffness was measured before and after cyclic testing. A maximum load to failure test was also conducted. Results were compared with one-way analysis of variance (ANOVA) and Fisher protected least significant difference (PLSD).
Results for axial stiffness show that AMBI, CS, XCS and FNLP are 2779.0, 2207.2, 3029.9 and 3210.7 N-m mm(-1), respectively. Rotational rigidity results are 4.5, 4.1, 17.1 and 18.7 N-m mm(-1). The average cyclic displacements were 0.75, 0.88, 0.80 and 0.65 mm, respectively. Destructive failure loads for AMBI, CS, XCS and FNLP were 2.3, 1.7, 1.6 and 1.9 kN, respectively.
The results of this experiment show statistically significant increases in axial stiffness for the FNLP compared with three traditional fixation methods. The FNLP demonstrates increased mechanical stiffness and combines the desirable features of current fixation methods.
本研究旨在比较新型股骨颈锁定板（FNLP）与其他当前固定方法治疗 C 型股骨颈骨折的生物力学稳定性。
将 40 个股骨标本分为几组，并制作垂直股骨颈骨折。每组分别采用以下方法进行修复：（CS）三枚平行松质骨螺钉；（XCS）两枚头内松质骨拉力螺钉和一枚骺板横向拉力螺钉；（FNLP）新型 FNLP，带有两枚 5.7 毫米锁定螺钉、一枚骺板拉力螺钉和两枚螺钉入骨干；和（AMBI）带有旋转移位螺钉的两孔、135° AMBI 板。所有组均进行 20000 次循环后轴向刚度变化测试，循环测试前后测量旋转刚度。还进行了最大失效负荷测试。结果采用单因素方差分析（ANOVA）和 Fisher 保护最小显著差异（PLSD）进行比较。
轴向刚度结果显示，AMBI、CS、XCS 和 FNLP 的刚度分别为 2779.0、2207.2、3029.9 和 3210.7 N-m mm(-1)。旋转刚度结果分别为 4.5、4.1、17.1 和 18.7 N-m mm(-1)。平均循环位移分别为 0.75、0.88、0.80 和 0.65 mm。AMBI、CS、XCS 和 FNLP 的破坏性失效负荷分别为 2.3、1.7、1.6 和 1.9 kN。
本实验结果表明，FNLP 与三种传统固定方法相比，轴向刚度有统计学显著增加。FNLP 表现出增加的机械刚度，并结合了当前固定方法的理想特征。
