TKA BONE CUTS — Hip & Knee Book | 合法醫療器材資訊網

2017年2月24日—MechanicalAlignment.ThegoalistoplacetheTKAinneutralmechanicalalignment.·ExtensionGap.Ifbonecutsaredonecorrectly(0fortibia ...

However, in the native knee, the posterior femoral condyles are not equal size and therefore a line across them is not parallel to the tibial cut, rather they are in 3° of valgus (to match the native tibial plateau angle of 3° varus).  You therefore cannot place a flat jig under the posterior femoral condyles to obtain a neutral rotation (it will cause your cuts to be internally rotated by 3°).  Instead you can take a jig that has 3 ° of external rotation dialed into it as compensation, and place it under the posterior femoral condyles to obtain a neutral rotation.  Alternatively, you can use other landmarks to orient the cutting jig to obtain neutral rotation.  Whitesides line is a vertical line parallel to the mechanical axis, or the Transepicondylar Axis Line (line connecting the medial and lateral epicondyles) is a horizontal line that is perpendicular to the mechanical axis.  Use ...