The left image shows a knee joint in a healthy rat. (White indicates cartilage.) The second image from the left shows a joint with grade 2 untreated osteoarthritis. The third image shows a joint with osteoarthritis that has worsened from grade 2 to grade 4 after six weeks of placebo therapy. The right image shows a joint with osteoarthritis that improved from grade 2 to grade 1 (mild) after six weeks of combination therapy with alphaKlotho and sTGFbR2. Credit: Salk Institute ***************************************************************** A combination of two previously studied osteoarthritis drugs works better than either drug alone. People with osteoarthritis, or...