Also known as “slipped stifles” is a common problem in small dogs. It is caused when the patellia, which has three parts; the femur (thigh bone), patella (knee cap), and tibia (calf), is not properly lined up. This causes a lameness in the leg or an abnormal gait in the dog. It is a disease that is present at birth although the actual misalignment or luxation does not always occur until much later. The rubbing caused by patellar luxation can lead to arthritis which is a degenerative joint disease. There are four grades of Patellar Luxation ranging from grade I, which is a occasional luxation causing temporary lameness in the joint, to grade IV where the turning of the tibia is severe and the patellia cannot be realigned manually. This causes a bowlegged appereance in the dog. The treatment for all grades of Patellar Luxation can be surgery.