Emara Khaled M, Mahmoud Ahmed Nageeb, Emara Ahmed K, Emara Mariam K
Khaled M Emara, Ahmed Nageeb Mahmoud, Ahmed K Emara, Mariam K Emara, Limb Reconstruction and Deformity Correction Unit, Orthopaedic Surgery Department, Ain Shams University Hospitals, Cairo 11566, Egypt.
World J Orthop. 2017 May 18;8(5):431-435. doi: 10.5312/wjo.v8.i5.431.
To review and study the effect of lengthening along the anatomical axis of long bones and its relation to the mechanical axis deviation.
We try in this review to calculate and discuss the exact clinical impact of lengthening along the anatomical axis of the femur on affecting the limb alignment. Also we used a trigonometric formula to predict the change of the femoral distal anatomical mechanical angle (AMA) after lengthening along the anatomical axis.
Lengthening along the anatomical axis of the femur by 10% of its original length results in reduction in the distal femoral AMA by 0.57 degrees. There is no objective experimental scientific data to prove that the Mechanical axis is passing the center of the hip to the center of the knee. There is wide variation in normal anatomical axis for different populations. In deformity correction, surgeons try to reproduce the normal usual bone shape to regain normal function, which is mainly anatomical axis.
Lengthening of the femur along its anatomical axis results in mild reduction of the distal femoral AMA. This may partially compensate for the expected mechanical axis lateralisation and hence justify its minimal clinical impact.
回顾并研究沿长骨解剖轴延长的效果及其与机械轴偏差的关系。
在本综述中，我们试图计算并讨论沿股骨解剖轴延长对肢体对线影响的确切临床影响。此外，我们使用三角函数公式预测沿解剖轴延长后股骨远端解剖机械角（AMA）的变化。
沿股骨解剖轴延长其原始长度的10%会导致股骨远端AMA减少0.57度。没有客观的实验科学数据证明机械轴是从髋关节中心穿过到膝关节中心的。不同人群的正常解剖轴存在很大差异。在畸形矫正中，外科医生试图重现正常的骨形状以恢复正常功能，这主要是解剖轴。
沿股骨解剖轴延长会导致股骨远端AMA轻度降低。这可能部分补偿预期的机械轴外偏，因此证明其临床影响最小。
