I hope your curiosity has been easy on your senses *wink*. Amazing, isn't it. This incision show's Billy's femur, To the left is the top end of Billy's knee. The incision is not yet complete, as Dr. Letson still has to continue to the top of Billy's hip, and to the lower end of Billy's knee, half way down the tibia. The previous image only show's the upper end of the prosthesis, consisting of this section of Billy's femur bone. There is another section of prosthesis attached to this, extending to the lower part of Billy's leg, and inserted into the lower leg bone called the Tibia. This lower section (not pictured) also includes the lower knee joint.