A 3D kinematic estimation of knee prosthesis using X-ray projection images: clinical assessment of the improved algorithm for fluoroscopy images.

In this paper, we propose three ideas to improve a kinematic estimation algorithm for total knee arthroplasty. The first is a two-step estimation algorithm that improves estimation accuracy by excluding certain assumptions needed for the pattern matching algorithm reported by Banks and Hodge. The second is incorporating a 3D geometric articulation model into the algorithm to improve estimation accuracy substantially for the depth translation, and to introduce contact points' trajectories between the articular surfaces.