I had my left knee reconstructed at 19 and the right at 30 and have had 8 surgeries total on both knees. I used a variety of MSM/Chondroitin/Glucosamine remedies for years and did not see any benefits. I think that strengthening the supporting muscles around the knee area have been the most beneficial thing I’ve done and have not any issues since I quit taking the supplements over 3 years ago. Just my .02