Application of three-dimensional reconstruction to improve the preoperative measurement accuracy and applicability of femoral neck torsion angle

Abstract Background: The femoral neck torsion angle (FNTA) is an important but often neglected parameter in assessments of the anatomical morphology of the femoral neck, which is often confused with the femoral neck anteversion angle (FNAA) in the current literature. Currently, the measurement methods reported in the literature all adopt the naked eye or two-dimensional (2D) visualization method, and the measurement parameters and details are not clearly defined. The objection of this research was to provide a reliable 3D method for determining the femoral neck axis, to improve the measurement method of the FNTA, and to analyze the anatomical and clinical significance of the results.Methods: Computed tomography (CT) data of 200 patients who received a lower extremity CT angiography examination were selected, and the bilateral femurs were reconstructed with three dimensional CT (3D CT). First, the 3D axis of the femoral neck was built. Second, the long axis of the cross section the femoral neck isthmus (FNI) and femoral neck basilar part (FNB) were confirmed by the “inertia axes” method, and the plane consisting of the long axis of the cross-section and the center of the femoral head was defined as the long axial plane. Third, the coronal plane of the proximal femur was determined through the long axis of the proximal femur and the femoral coronal. Finally, the FNTAs (the angles between the long axial planes and the coronal plane of the proximal femur) of FNI and FNB were measured. The size of FNTA was compared between the sexes and sides and different locations, the correlation between the parameters and age, height and weight were evaluated.Results: The difference in FNTA was statistically significant between the isthmus and the basilar part (isthmus 30.58 ± 8.90° vs. basilar part 23.79 ± 3.98°; p < 0.01). Significant difference in the FNTA was observed between the sexes (males 31.99 ± 9.25° vs. females 27.49 ± 7.19°; p < 0.01). The increase in FNTA from the basilar part to the isthmus was 6.79 ± 8.06°, and the male (7.87 ± 8.57°) was greater than the female (4.44 ± 6.23°, p < 0.01). However, no significant difference in the values was observed between sides. Height exerted the greatest effect on the FNTA according to the correlation analysis (r = 0.255, p＜0.001). Conclusions: This study found a reliable 3D method for the determination of the femoral neck axis improved the measurement method of the FNTA and made it more accurate and repeatable. The results provided a methodological basis and theoretical support for the research and development of internal fixation device for femoral neck fracture and the spatial configuration of implants in treatment. And, the optimal opening point of the femoral medullary cavity was recommended to locate at the posterior position of the top of the femoral neck cross-section during hip replacement.

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Three-Dimensional Morphological Analysis of the Femoral Neck Torsion Angle - An Anatomical Study.

10.21203/rs.2.19917/v1 ◽

2020 ◽

Author(s):

Ru-yi Zhang ◽

Xiu-yun Su ◽

Jing-xin Zhao ◽

Jian-tao Li ◽

Li-cheng Zhang ◽

...

Keyword(s):

Femoral Neck ◽

Torsion Angle ◽

Linear Regression Analysis ◽

Three Dimensional ◽

Anatomical Study ◽

Ct Reconstruction ◽

Methodological Foundation ◽

Neck Fracture ◽

The Difference ◽

Neck Torsion

Abstract Background: The femoral neck torsion angle (FNTA) is a very important but often neglected parameter in assessments of the anatomical morphology of the femoral neck, and it is often confused with the femoral neck anteversion angle (FNAA) in the current literature. Currently, naked eye or two-dimensional literature (2D) visualization method was used in the literature that the measurement method reported, and the measurement parameters and details are not clearly defined. The objection of this research was to establish a three-dimensional (3D) method to measure the FNTA, and to analyse the anatomical and clinical significance of the results. Methods: Computed tomography (CT) data of 200 patients who received a lower extremity CT angiography examination were selected for the three-dimensional CT (3D CT) reconstruction of bilateral femurs by using Mimics software. The 3D axis of the femoral neck was built, and the FNTAs of the isthmus and the basilar part were measured using the “inertia axes” method. SPSS software was used for statistical analyses. Results: The difference in FNTA was statistically significant between the isthmus and the basilar part (isthmus 30.58 ± 8.90° vs. basilar part 23.79 ± 3.98°; p < 0.01). Significant differences in the FNTA were observed between the sexes (males 31.99 ± 9.25° vs. females 27.49 ± 7.19°; p < 0.01). The increase in FNTA from the basilar part to the isthmus was 6.79 ± 8.06°, and the increase observed in men (7.87 ± 8.57°) was larger than that in women (4.44 ± 6.23°, p < 0.01). However, no significant differences in the values were observed between sides. According to the correlation analysis, height exerted the greatest effect on the FNTA (r = 0.255, p＜0.001), and the stepwise linear regression analysis produced the following final regression model: Y = -27.685 + 35.134 × HEIGHT (p < 0.001, R2 = 0.095). Conclusions: This study provides a new and reliable 3D method for measuring the FNTA. The method and results provide a methodological foundation and theoretical support for the research and development of internal fixation devices and configurations of the space for an implant designed to treat a femoral neck fracture. And, the optimal opening point of the femoral medullary cavity is recommended to be located at the posterior position of the top of the femoral neck cross-section during hip replacement.

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Three-Dimensional Reconstruction Modeling of the Spatial Displacement, Extent and Rotational Orientation of Undisplaced Femoral Neck Fractures

Medicine ◽

10.1097/md.0000000000001393 ◽

2015 ◽

Vol 94 (39) ◽

pp. e1393 ◽

Cited By ~ 4

Author(s):

Xin Fu ◽

Gui-Jun Xu ◽

Zhi-Jun Li ◽

Chang-Ling Du ◽

Zhe Han ◽

...

Keyword(s):

Femoral Neck ◽

Three Dimensional ◽

Femoral Neck Fractures ◽

Three Dimensional Reconstruction ◽

Spatial Displacement ◽

Dimensional Reconstruction ◽

Rotational Orientation

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Methods for three-dimensional reconstruction of cellular components within a thick section

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141871 ◽

1986 ◽

Vol 44 ◽

pp. 18-21

Author(s):

J. Frank ◽

B. F. McEwen ◽

M. Radermacher ◽

C. L. Rieder

Keyword(s):

Tilt Angle ◽

Tomographic Reconstruction ◽

3D Structure ◽

Three Dimensional ◽

Thick Section ◽

Three Dimensional Reconstruction ◽

Axis Ratio ◽

Dimensional Reconstruction ◽

Cellular Components

The tomographic reconstruction from multiple projections of cellular components, within a thick section, offers a way of visualizing and quantifying their three-dimensional (3D) structure. However, asymmetric objects require as many views from the widest tilt range as possible; otherwise the reconstruction may be uninterpretable. Even if not for geometric obstructions, the increasing pathway of electrons, as the tilt angle is increased, poses the ultimate upper limitation to the projection range. With the maximum tilt angle being fixed, the only way to improve the faithfulness of the reconstruction is by changing the mode of the tilting from single-axis to conical; a point within the object projected with a tilt angle of 60° and a full 360° azimuthal range is then reconstructed as a slightly elliptic (axis ratio 1.2 : 1) sphere.

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Three-Dimensional Reconstruction of Native Androctonus Australis Hemocyanin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100181014 ◽

1990 ◽

Vol 48 (1) ◽

pp. 452-453

Author(s):

Nicolas Boisset ◽

Jean-Christophe Taveau ◽

Jean Lamy ◽

Terence Wagenknecht ◽

Michael Radermacher ◽

...

Keyword(s):

Electron Microscopy ◽

Solid Body ◽

Body Surface ◽

Three Dimensional ◽

Staining Technique ◽

Three Dimensional Reconstruction ◽

Dimensional Reconstruction ◽

View Reconstruction ◽

Surface Representations ◽

Top View

Hemocyanin, the respiratory pigment of the scorpion Androctonus australis is composed of 24 kidney shaped subunits. A model of architecture supported by many indirect arguments has been deduced from electron microscopy (EM) and immuno-EM. To ascertain, the disposition of the subunits within the oligomer, the 24mer was submitted to three-dimensional reconstruction by the method of single-exposure random-conical tilt series.A sample of native hemocyanin, prepared with the double layer negative staining technique, was observed by transmisson electron microscopy under low-dose conditions. Six 3D-reconstructions were carried out indenpendently from top, side and 45°views. The results are composed of solid-body surface representations, and slices extracted from the reconstruction volume.The main two characters of the molecule previously reported by Van Heel and Frank, were constantly found in the solid-body surface representations. These features are the presence of two different faces called flip and flop and a rocking of the molecule around an axis passing through diagonnally opposed hexamers. Furthermore, in the solid-body surface of the top view reconstruction, the positions and orientations of the bridges connecting the half molecules were found in excellent agreement with those predicted by the model.

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Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180045 ◽

1990 ◽

Vol 48 (1) ◽

pp. 258-259

Author(s):

J.L. Carrascosa ◽

G. Abella ◽

S. Marco ◽

M. Muyal ◽

J.M. Carazo

Keyword(s):

Three Dimensional ◽

The Other ◽

Two Dimensional ◽

Series Method ◽

Three Dimensional Reconstruction ◽

Structural Components ◽

E Coli ◽

Dimensional Reconstruction ◽

Morphogenetic Factors ◽

Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

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