For surgical preferences, the Femur Rotational Axis can be chosen as which?

• A. CT-based Alignment
• B. Anatomic Axis
• C. PCA or Manually Define
• D. None

Answer: (C)

Rotational alignment of the femoral component in knee surgery is set against a reference axis, and the two practical options are using the posterior condylar axis or defining the axis manually. The posterior condylar axis is a reliable, identifiable landmark on the back of the femoral condyles and usually provides good patellofemoral tracking and knee mechanics. However, when those landmarks are distorted or unreliable, the surgeon can define the axis manually to tailor rotation to soft-tissue balance and individual anatomy. This combination—PCA as the standard reference, with manual definition as needed—covers common surgical preferences for setting the femur’s rotational axis.