Ji Hyung-Min, Jin Dong San, Han Jun, Choo Ho-Sik, Won Ye-Yeon
Department of Orthopaedic Surgery, Ajou University of College of Medicine, 164, World Cup-ro, Yeongtong-gu, Suwon, 443-721, South Korea.
Knee Surg Sports Traumatol Arthrosc. 2016 Aug;24(8):2402-6. doi: 10.1007/s00167-015-3506-y. Epub 2015 Jan 20.
Accurate rotational alignment of the femoral component is of vital importance for successful total knee arthroplasty (TKA). Two anatomical references located on the anterior femur were recently introduced. To determine which is more reliable reference axis for the femoral component rotation in female patients receiving TKA, the trochlear anterior line was compared with the femoral anterior tangent line.
Preoperative computed tomography in 76 patients receiving TKA for varus deformity was performed, and the images were reconstructed into three-dimensional models. The trochlear anterior line was defined as the line connecting the most anterior portion of the lateral and medial femoral condyles and the femoral anterior tangent line as the line parallel to distal anterior femoral surface. The two angles between these reference axes and the surgical transepicondylar axis (TEA) in three-dimensional images (trochlear anterior line/TEA, femoral anterior tangent line/TEA) were measured. The correlation between these two angles was computed. We investigated to see whether a significant difference in variance existed.
The trochlear anterior line was internally rotated by 6.1° ± 2.5° with respect to TEA, whereas the femoral anterior tangent line by 9.5° ± 3.8°. The trochlear anterior line was externally rotated by 3.4° ± 3.3° with respect to the femoral anterior tangent line. There was a significant correlation between the trochlear anterior line/TEA and the femoral anterior tangent line/TEA.
The variance of the trochlear anterior line/TEA was significantly smaller than that of the femoral anterior tangent line/TEA demonstrating a more consistent distribution. When conventional reference axes such as the posterior condylar axis or the anteroposterior axis are unclear or differ, surgeons can rely on these alternative references. When trochlear anterior line and femoral anterior tangent line contradicts, the former might be more reliable for the rotational alignment of the femoral component in female patients.
Case series with no comparison group, Level IV.
股骨组件的精确旋转对线对于全膝关节置换术（TKA）的成功至关重要。最近在前股骨上引入了两个解剖学参考标志。为了确定在接受TKA的女性患者中哪个是股骨组件旋转更可靠的参考轴，将滑车前线与股骨前切线进行了比较。
对76例因膝内翻畸形接受TKA的患者进行术前计算机断层扫描，并将图像重建为三维模型。滑车前线定义为连接股骨内外侧髁最前部的线，股骨前切线定义为与股骨远端前表面平行的线。在三维图像中测量这些参考轴与手术髁间轴（TEA）之间的两个角度（滑车前线/TEA，股骨前切线/TEA）。计算这两个角度之间的相关性。我们研究了方差是否存在显著差异。
滑车前线相对于TEA内旋6.1°±2.5°，而股骨前切线相对于TEA内旋9.5°±3.8°。滑车前线相对于股骨前切线外旋3.4°±3.3°。滑车前线/TEA与股骨前切线/TEA之间存在显著相关性。
滑车前线/TEA的方差显著小于股骨前切线/TEA的方差，表明分布更一致。当传统的参考轴如后髁轴或前后轴不明确或不同时，外科医生可以依赖这些替代参考。当滑车前线和股骨前切线相互矛盾时，对于女性患者股骨组件的旋转对线，前者可能更可靠。
无对照组的病例系列，IV级。
