Arthritis: How to treat arthritis
By Gil Riley
19 November 2009 09:53
Far from being a life sentence, with the right approach, it's possible to fight arthritis and give your horse an active, enjoyable life. Vet Gil Riley helps us prepare for battle.
There are a variety of treatments that can be used, either on their own or in combination with others.
The most widely used treatment is phenylbutazone, better known as bute. This is both an anti-inflammatory and a painkiller so, apart from masking the pain, it decreases the inflammation occurring within the joint. Although effective and reasonably safe, some health problems can develop in horses fed bute, particularly if it’s for high dosages over long periods. These include stomach ulceration, colic and liver damage. Another disadvantage is that bute has been shown to undermine the regeneration of joint cartilage. Although these effects are small, they do mean that in efforts to make our horses more comfortable, we may be actually worsening the situation in the long-term.
Rather than treating the whole body, as in the case of bute, joint injections are a more direct method. This involves injecting medicines into the affected joint and thereby delivering a high dose to exactly where it’s required. For this reason, joint injections have become a popular method of treating early stage arthritis and reducing inflammation. The two types of medication most often used are corticosteroids and hyaluronic acid. Corticosteroids are the most common drug-injected antiinflammatory. They shut down the cycle of inflammation that rages in the arthritic joint, and their positive effects can be dramatic, leading to rapid improvement in joint swelling and lameness. However, repeat administration is often needed and their use carries the slight risk of inducing laminitis. Hyaluronic acid is a normal constituent of synovial fluid. In addition to lubricating the joint cartilage, there is good evidence that it also impedes some of the mediators involved in joint inflammation, which damage the cartilage.
Some arthritic joints are best treated by keyhole surgery, a process known as arthroscopy. This is most likely to be advised by your vet if more conservative treatments have failed to address the problem. Arthroscopy involves making two keyhole openings into the joint. A small camera (known as a scope) is inserted into one of these holes and the internal structures of the joint carefully examined. If any debris needs to be removed it can be done by the surgeon inserting tools through the other opening. Provided the arthritis is not too advanced, the prognosis after surgery is often good.
Irap therapy uses the horse’s own natural protection to fight inflammation in the joint. A blood sample is taken and the sample cultured to encourage blood cells to produce large quantities of anti-inflammatory proteins. The resulting solution is injected directly into the joint, and results to date are promising. The most revolutionary treatment being developed is gene therapy. In US studies, researchers have been able to shut down the vicious inflammatory cycle in a horse’s arthritic joint by injecting a harmless virus that carries genes directly in to the joint, instructing the horse’s own cells to switch off the inflammation. The results, although dramatic, are currently short-lived. If a way can be found to increase the duration of action, we may be seeing an exciting new chapter opening on our approach to treating arthritis.