Canine osteoarthritis and treatments: a review

Arthritis is a commonly occurring chronic illness in human and animals alike. Among all domestic and pet animal species, dogs suffer from arthritis more often because of excessive running or exercise, injury, and/or genetic predisposition. Presently, one in four of 77.2 million pet dogs in the United States are diagnosed with some form of arthritis. In dogs, osteoarthritis is more common than rheumatoid arthritis and pain is the number one observation. Osteoarthritis, also known as degenerative joint disease, is a slowly progressive inflammatory disease, which is characterized by degeneration of the cartilage, hypertrophy of bone at the margins, and changes in the synovial membrane, and that eventually results in pain and stiffness of joints. Alterations in joint structures, decreased flexibility, and severe pain ensues, due to lack of hydration and inflammation. Cells within the damaged joints release pro-inflammatory cytokines, which further the inflammatory process. This causes more breakdown of the cartilage collagen type II and proteoglycans, which results in a perpetual destructive cycle. This perpetuating cycle ultimately results in cartilage destruction, subchondral bone thickening, and synovial membrane inflammation. This review focuses on osteoarthritis, the disease, causes, treatments, and presents a glimpse of some new therapies under study.