1. The bone-cutting line of femoral component is up to upper line. The femoral component rotate an angle of 3° and reproduce physiological patella groove, which are in favor to movement of patellar component and the rotation of femur and tibia;
2. The top part of patellar groove extended outside and simulating knee anatomy, which makes patellar prosthesis keep contact with groove during flexion and extension.
3. The design of deep patellar grooves for femoral component provides better tracking for patellar and prevent subluxation.
4. Spherical shape(domed shape)of patellar component increases Petella/Femoral contact surface, decrease contact stress of polyethylene, and apparently improves polyethylene wearability and reduces production of wear debris so as to prevent bone dissolution.
5. The design of three-peg fixation for the Patella Component prevents itself from rotation.
