This photo show's Billy's upper knee joint. Dr. Letson has released all of the tendon's, ligament's, and muscle's from their attachment points, and is removing the femur from Billy's leg. During this surgery, Dr. Letson was pleased at the fact that he was able to save all of Billy's muscle tissue. This proved to be very crucial in Billy's recovery, and subsequent re-habilitation. As you know, Billy's leg was opened two more time's. The original prosthesis was removed due to infection, and replaced with a "temporary" spacer so that Billy would have a greater chance at surviving his bone marrow transplant. After a successful BMT, Billy's leg was re-opened, and the spacer was replaced by another prosthesis, like the one pictured in the photo of his 1st surgery. Billy will have to undergo yet another prosthesis replacement when he stops growing, to install an "adult" prosthesis (femur and knee).