Gooding CR et al. – Total knee arthroplasty is a very successful procedure in the treatment of end–stage osteoarthritis of the knee. However, the various components of the arthroplasty are interdependent, and correct spatial orientation in all 6 degrees of freedom is crucial for optimal functioning and longevity of the implant. In particular, the rotation of the femoral component is important for balancing the knee in flexion and for proper functioning of the patellofemoral joint. From a historical perspective, one can appreciate the evolution of the various techniques used to achieve correct alignment.