The following article from Laura Werner, DVM, MS, DACVS, a veterinarian at Hagyard Equine Medical Center near Lexington, Kentucky, describes a variety of therapies used for treating joints that are damaged or inflamed.
From the moment a horse stands and walks, his joints are at a steady rate of degradation. Repeated trauma or stress to the joint during everyday riding, athletic training or performance, results in joint inflammation at some level in your horse, which leads to the start of arthritis.
Osteoarthritis is the inflammation and subsequent bony changes that occur as a result of damage to the cartilage padding the ends of bones in joints. As osteoarthritis progresses, veterinarians have several different therapy options available to help combat your horses aching joints. The goals of treatment are to minimize pain and inflammation, to slow down the degenerative process and to control the clinical signs of joint disease while extending the useful life of the horse.
Success is better achieved with early normalization of the acutely inflamed joint before cartilage damage occurs and early initiation of therapy before the condition becomes chronic. Treatment often includes a combination of therapies to provide the best response. Non-steroidal anti-inflammatory drugs (NSAIDs) are one of our first lines of defense with treatment of joint disease in the horse. These include phenylbutazone, flunixin (Banamine), ketoprofen, firocoxib and diclofenac.
Newer NSAID’s such as firocoxib (Equioxx) and topical diclofenac (Surpass) are good options as they are safer for longer-term use with less ulcerogenic effects than phenylbutazone or flunixin. Longer (14-day treatment periods) of the drug firocoxib are allowed within drug rule guidelines for competition.
Oral joint supplements are important as they do more to prevent inflammation and joint breakdown than they do to treat it once it has started. Two excellent first-level joint nutraceuticals are glucosamine and chondroitin sulfate, as these products exhibit anti-inflammatory properties for joints.
There is a wide variety in the cost, amount of nutrients in each product, and quality control in manufacturing, so it is important to purchase your supplements from a reputable source, such as veterinary-owned companies.
Additional supplement ingredients such as hyaluronic acid (HA), MSM (methysufonylmethane) and avocado soybean unsaponifiables (ASU) have also been shown to reduce joint inflammation and improve the appearance of cartilage in patients with arthritis.
Sodium hyaluronate is a major component of joint fluid and cartilage. Products containing hyaluronate or hyaluronic acid are available for intravenous (such as Legend) or intra-articular use. Research has shown decreased lameness and decreased inflammatory factors in the joint. It has few adverse reactions, and intravenous use of the product has a wide distribution throughout body.
The intra-articular products are often used in combination with corticosteroids.
Hyaluronate is legal for competitions and the intravenous product is allowed during FEI competitions.
Polysulfated glycosaminoglycans (Adequan) also help decrease inflammation, improve cartilage remodeling, improve mobility of the joint and help decrease pain. The product can also be used intramuscularly or intra-articularly. The intra-articular products are also often used in combination with corticosteroids. The product is very safe and is also allowed for use during competitions.
Tildren, a bisphosphanate compound similar to drugs used for osteoporosis in humans, is another therapy for joint disease. It helps regulate the remodeling process of bone and clinical trials show positive results for arthritis of hocks, spine and navicular syndrome.
Still a popular option for direct joint therapy is intra-articular injections with corticosteroids. Corticosteroids are powerful anti-inflammatory agents for the joint and achieve long lasting anti-inflammatory effects by inhibiting the tissues with in the joint from releasing several chemical mediators that cause the initial process of inflammation--heat, pain, swelling and excess fluid.
Triamcinolone and betamethasone may help protect cartilage at lower doses, while betamethasone may be a safer choice in an older patient with metabolic disease.
Intra-articular injections of hyaluronate or glycosaminoglycan products alone will maintain some horses as well.
Newer therapies, such as regenerative medicine, also show positive results in the treatment of joint disease. IRAP (or interleukin receptor antagonist protein) is a product that helps block the negative effects of interleukin 1 in the joint. Interleukin 1 increases inflammation in the joint and increases the degradation of protein within the joint. The product is derived from the patient’s blood, then used directly in the joint for a series of 3-5 injections. The product is easy to use, has few adverse reactions and is safe to use around the time of competitions.
Platelet rich plasma (PRP) is al so obtained from the patient’s own blood and is rich in growth factors to help tissue healing and is another option in the treatment of joint disease. PRP is easy to use, relatively low cost and is available for almost immediate use.
Stem cells derived from a patient’s own fat or bone marrow or banked stem cells from a donor horse are also used frequently. The fat or bone marrow is collected and stem cells are cultured over 2-3 weeks to be injected into an affected joint or joints. Stem cells from a donor source are available for immediate use, but reactions occur at a higher rate since they are not derived from the individual patient. Technology is improving for stem cells to be selectively cultured to help repair cartilage within the joint. Gene therapy may also hold the key in the future for treatment of joint disease.