Akman Alp, Demirkan Fahir, Sabir Nuran, Oto Murat, Yorukoglu Cagdas, Kiter Esat
Department of Orthopaedics and Traumatology, School of Medicine, Pamukkale University, Denizli, Turkey.
Department of Radiology, School of Medicine, Pamukkale University, Denizli, Turkey.
Indian J Orthop. 2017 Jan-Feb;51(1):49-54. doi: 10.4103/0019-5413.197219.
Femoral bowing plane (FBP) is the unattended subject in the literature. More over the femoral shaft with its bowing is neglected in established anteversion determination methods. There is limited information about the relationship between FBP and anteversion. Thus we focused on this subject and hypothesized that there could be an adaptation of FBP to anteversion.
FBP is determined on three-dimensional solid models derived from the left femoral computerized tomography data of 47 patients which were taken before for another reason and comparatively evaluated with anteversion. There were 20 women and 27 men. The mean age of patients was 56 years (range 21-84 years).
The anteversion values were found as the angle between a distal condylar axis (DCA) and femoral neck anteversion axis (FNAA) along an imaginary longitudinal femoral axis (LFA) in the true cranio-caudal view. The FBP was determined as a plane that passes through the centre-points of three pre-determinated sections on the femoral shaft. The angles between DCA, FNAA and FBP were comparatively evaluated. The independent samples -test was used for statistical analysis. At the end, it was found that FBP lies nearly perpendicular to the anteversion axis for the mean of our sample which is around 89° in females and 93° in males (range 78-102°). On the other hand, FBP does not lie close to the sagittal femoral plane (SFP); instead, there is an average 12.5° external rotation relative to the SFP. FBP is correlated well with anteversion in terms of FBP inclination from SFP and femoral torsion (i.e., angle between FBP and femoral neck anteversion axis ( < 0.001; = 0.680 and = -0.682, respectively). Combined correlation is perfect ( = 1) as the FBP, SFP, and posterior femoral plane forms a triangle in the cranio-caudal view.
We found that FBP adapts to anteversion. As FBP lies close to perpendicularity for the mean, femoral component positioning perpendicular to the FBP can be an alternate way in the replacement surgeries. In addition, it has been found that FBP lies externally rotated relative to the SFP.
股骨弓状平面（FBP）在文献中未受到关注。此外，在已有的前倾角测定方法中，带有弓形的股骨干被忽视了。关于FBP与前倾角之间的关系，信息有限。因此，我们关注了这个问题，并假设FBP可能会适应前倾角。
FBP是在从47例患者的左股骨计算机断层扫描数据导出的三维实体模型上确定的，这些数据因其他原因之前已采集，并且与前倾角进行了比较评估。其中有20名女性和27名男性。患者的平均年龄为56岁（范围21 - 84岁）。
在前倾角值方面，是在真正的颅尾视图中沿着假想的股骨干纵轴（LFA）确定远端髁轴（DCA）与股骨颈前倾角轴（FNAA）之间的角度。FBP被确定为一个穿过股骨干上三个预先确定截面中心点的平面。对DCA、FNAA与FBP之间的角度进行了比较评估。采用独立样本t检验进行统计分析。最后发现，对于我们样本的平均值，FBP几乎垂直于前倾角轴，女性约为89°，男性约为93°（范围78 - 102°）。另一方面，FBP并不靠近股骨干矢状面（SFP）；相反，相对于SFP平均有12.5°的外旋。就FBP相对于SFP的倾斜度和股骨扭转（即FBP与股骨颈前倾角轴之间的角度）而言，FBP与前倾角相关性良好（分别为<0.001；r = 0.680和r = -0.682）。由于在颅尾视图中FBP、SFP和股骨干后平面形成一个三角形，综合相关性完美（r = 1）。
我们发现FBP适应前倾角。由于FBP平均值接近垂直，在置换手术中，将股骨部件垂直于FBP定位可能是一种替代方法。此外，还发现FBP相对于SFP向外旋转。
