Scientists haven't yet found a replacement for good ol cartilage. In the knee, this is the medial and lateral menisci, and covering the ends of the femur and tibia, articular cartilage. Stem cells may someday provide a solution to growing cartilage in a lab, but that's in the future.

In the meantime, joint replacement is a wonderful, life changing procedure. To work, it requires a skilled surgeon and a motivated patient. Like a lot of things, there are no shortcuts.