This is Duke. He's 71/2 and we believe he tore his ACL this winter when he came charging down my stairs and went flying into the wall. Surgery is not an option with his age. My vet, Alpine Vet in Bend, OR recommended the Austin & Kat Get Up and Go wafers. They have been a game changer. He's able to go on long walks, run and play, and get up on the bed without pain. If he strains it, I just give him an extra half. Thank you for this amazing product!