Healthy Joints are critical to achieving maximum performance in our equine athlete partners. Healthy joints are made up of articular cartilage and joint fluid. Cartilage helps the bones move smoothly against one another. Joint fluid, a viscous fluid made up of hyaluronic acid and proteins, aids in shock absorption.
Joints can become damaged through trauma or degenerative joint diseases, such as osteoarthritis, trauma, or repetitive motions that create inflammation. The effect of these processes is a net loss of cartilage and viscosity of the joint fluid. The joint fluid loses hyaluronic acid which decreases its viscosity and ability to absorb concussion. These changes can cause pain as bones rub together without the cushioning. The discomfort caused by decreased joint health can present many different ways. Some examples include stiffness, lameness, positive flexion test, resistance to extending legs fully in work, hesitance to jump, or a reaction to landing from a jump.
Current proactive treatments include:
1. Adequan is a commonly used treatment for joint support. Adequan is a polysulfated glycosaminoglycan commonly abbreviated PSGAG. This is chemically similar to the substances found in cartilage. Adequan improves joint function in two ways. It increases hyaluronic acid concentration in joint fluid and inhibits proteolytic enzymes that break down cartilage and joint fluid. Adequan has the benefit of decreasing inflammation in the synovial membrane that surrounds each joint which can decrease pain.
It is recommended that an Adequan series of seven injections be given in the muscle twice a year. Studies have shown that Adequan reaches joints within two hours of injection. In forty-eight hours post injection, Adequan causes increased levels of hyaluronic acid in joint spaces. Within ninety-six hours Adequan can be found in joint cartilage.
2. Legend is another treatment for joint support that is frequently prescribed. Legend is hyaluronate sodium, commonly known as hyaluronic acid. The hyaluronate molecules are long chains that form a network with existing joint fluid. This helps restore the lubricating effect of joint fluid and eases the pain. It causes change within days of being injected. Legend is a great choice for extra joint support before a show.
3. Pentosan is a compounded drug that has anti-inflammatory properties. A dose is given in the muscle once weekly for four weeks, then once a month. It is currently not sold in the United States and therefore must be compounded by a pharmacy. It is not regulated by the FDA at this time. Starwood veterinarians recommend the use of FDA approved medications whenever possible.
These medication can be used as both a preventative measure and to slow the progression of osteoarthritis once it has begun. We encourage you to schedule an exam so that Starwood veterinarians can discuss a proactive approach to protecting your horse’s joints.