Shimosawa Hiroshi, Nagura Takeo, Harato Kengo, Kobayashi Shu, Nakamura Masaya, Matsumoto Morio, Niki Yasuo
Department of Orthopaedic Surgery, Keio University School of Medicine, Shinanomachi 35, Shinjyuku-ku, Tokyo, 1608582, Japan.
Surg Radiol Anat. 2019 Dec;41(12):1489-1495. doi: 10.1007/s00276-019-02323-7. Epub 2019 Sep 13.
Anatomically, the femoral bone shows sagittal and coronal bowing. Pronounced bowing would affect femoral implant surgery accuracy, but factors associated with degrees of three-dimensional (3D) femoral bowing have not yet been identified. This study measured 3D femoral bowing and examined the correlation between 3D femoral bowing and risk factors.
3D femoral bone models of unaffected legs from 125 patients were reconstructed from computed tomography data. A trans-epicondylar axis (TEA)-based coordinate system was introduced into bone models and the reproducibility of this coordinate system was evaluated. The cross-sectional contours of the femoral canal were extracted along the vertical axis of the TEA-based coordinate system, and the angles of 3D femoral bowing were examined.
The reproducibility to set the coordinate was very high. Total, sagittal, and coronal femoral bowing were 8.9 ± 1.8°, 8.7 ± 1.8°, and 0.1 ± 1.9°, respectively. There was no significant difference in the degrees of femoral bowing between males and females. Total, coronal, and sagittal femoral bowing correlated with age, height, and femoral length, but only femoral coronal bowing correlated with bone mineral density (BMD) of the femur and lumbar spine.
We introduced a highly reproducible method for measuring femoral sagittal and coronal bowing by constructing a femoral 3D coordinate system. Anterior femoral bowing was the dominant direction of bowing in our Japanese cohort, whereas the degree of lateral bowing correlated with age, height, femoral length, and BMD. Our results suggest that lateral femoral bowing could increase with aging and decreasing BMD.
在解剖学上，股骨呈现矢状面和冠状面弯曲。明显的弯曲会影响股骨植入手术的准确性，但与三维（3D）股骨弯曲程度相关的因素尚未明确。本研究测量了3D股骨弯曲，并检查了3D股骨弯曲与危险因素之间的相关性。
从125例患者未受影响的腿部的计算机断层扫描数据重建3D股骨模型。将基于经髁上轴（TEA）的坐标系引入骨模型，并评估该坐标系的可重复性。沿着基于TEA的坐标系的垂直轴提取股骨髓腔的横截面轮廓，并检查3D股骨弯曲的角度。
设置坐标系的可重复性非常高。股骨总弯曲、矢状面弯曲和冠状面弯曲分别为8.9±1.8°、8.7±1.8°和0.1±1.9°。男性和女性之间股骨弯曲程度没有显著差异。股骨总弯曲、冠状面弯曲和矢状面弯曲与年龄、身高和股骨长度相关，但只有股骨冠状面弯曲与股骨和腰椎的骨密度（BMD）相关。
我们通过构建股骨3D坐标系引入了一种高度可重复的测量股骨矢状面和冠状面弯曲的方法。在我们的日本队列中，股骨前向弯曲是弯曲的主要方向，而外侧弯曲程度与年龄、身高、股骨长度和BMD相关。我们的结果表明，股骨外侧弯曲可能随着年龄增长和BMD降低而增加。
