UMR 7179 CNRS-Muséum National d'Histoire Naturelle, Paris Cedex, France.
J Anat. 2012 Nov;221(5):465-76. doi: 10.1111/j.1469-7580.2012.01565.x. Epub 2012 Sep 12.
A common problem in the quantification of the orientation of the femoral neck is the difficulty to determine its true axis; however, this axis is typically estimated visually only. Moreover, the orientation of the femoral neck is commonly analysed using angles that are dependent on anatomical planes of reference and only quantify the orientation in two dimensions. The purpose of this study is to establish a method to determine the three-dimensional orientation of the femoral neck using a three-dimensional model. An accurate determination of the femoral neck axis requires a reconsideration of the complex architecture of the proximal femur. The morphology of the femoral neck results from both the medial and arcuate trabecular systems, and the asymmetry of the cortical bone. Given these considerations, two alternative models, in addition to the cylindrical one frequently assumed, were tested. The surface geometry of the femoral neck was subsequently used to fit one cylinder, two cylinders and successive cross-sectional ellipses. The model based on successive ellipses provided a significantly smaller average deviation than the two other models (P < 0.001) and reduced the observer-induced measurement error. Comparisons with traditional measurements and analyses on a sample of 91 femora were also performed to assess the validity of the model based on successive ellipses. This study provides a semi-automatic and accurate method for the determination of the functional three-dimensional femoral neck orientation avoiding the use of a reference plane. This innovative method has important implications for future studies that aim to document and understand the change in the orientation of the femoral neck associated with the acquisition of a bipedal gait in humans. Moreover, the precise determination of the three-dimensional orientation has implications in current research involved in developing clinical applications in diagnosis, hip surgery and rehabilitation.
在确定股骨颈方向的过程中，一个常见的问题是难以确定其真实轴线；然而，该轴线通常仅通过目测进行估计。此外，股骨颈的方向通常通过依赖于解剖参考平面的角度进行分析，仅在二维平面上量化其方向。本研究旨在建立一种使用三维模型确定股骨颈三维方向的方法。准确确定股骨颈轴线需要重新考虑股骨近端的复杂结构。股骨颈的形态既来自内侧和弧形小梁系统，也来自皮质骨的不对称性。考虑到这些因素，除了经常假设的圆柱形模型外，还测试了另外两种替代模型。随后，使用股骨颈的表面几何形状拟合一个圆柱、两个圆柱和连续的横截面椭圆。基于连续椭圆的模型比另外两个模型（P < 0.001）提供了更小的平均偏差，并减少了观察者引起的测量误差。还对 91 个股骨样本进行了与传统测量和分析的比较，以评估基于连续椭圆的模型的有效性。本研究提供了一种半自动且准确的方法，用于确定功能三维股骨颈方向，避免使用参考平面。这种创新方法对于未来旨在记录和理解与人类获得双足步态相关的股骨颈方向变化的研究具有重要意义。此外，精确确定三维方向对当前涉及诊断、髋关节手术和康复的临床应用开发的研究具有重要意义。
