Galloping down a cross-country course, leaping three-foot fences or sliding to a stop puts an enormous amount of stress on fine, delicately built equine legs. But there is a lot going on behind the scenes. A sound horse maintains balanced joint function. But joints that bend and give to absorb that shock are comprised of structures—bone, cartilage, soft tissues, protective synovial fluid—that can all break down. Horse owners seek out both oral supplements and systemic injections, which are popular defenses against joint problems. But sometimes therapy goes beyond these approaches and directly into the joint itself.
To Inject or Not to Inject
Talk to your veterinarian about your horse’s soundness and performance issues to determine whether joint injections will be beneficial. Bill Moyer, DVM, head of the Large Animal Department at Texas A&M University, has been practicing veterinary medicine for more than 30 years. Along with Jim Schumacher, DVM, of the University of Tennessee, he co-authored A Guide to Equine Joint Injections (Veterinary Learning Systems Co., 2002). “Athletes seldom have just one thing wrong. Often we are looking at changes in the hocks, a sore back, some navicular changesand maybe the feet are in bad shape. In performance horses, there’s just a lot of wear and tear,” Dr. Moyer says.
Many things can go wrong in an equine joint, but one of the most common problems is arthritis, or degenerative joint disease, which leads to progressive destruction of joint structures. There is no cure for this disease, but managing it starts with a veterinary lameness exam to confirm diagnosis. Simple flexion tests, diagnostic nerve blocks and radiographs (X-rays) to evaluate bony changes are all used during the exam. MRI technology is also available, which gives veterinarians a good look at both bone and soft tissues, but the cost is prohibitive for the majority of horse owners.
Dr. Moyer says the most common joints to inject include the hock, pastern, coffin joint, fetlock, carpal (knee) and stifle joints. Keep in mind that some joints (knee, stifle and hock) are complex joints made up of more than one joint (for example, the hock has four joints).
Dr. Moyer continues, “Treating joints, the first thing that you need is a diagnosis to know what you are attempting to treat. If you have a swollen knee and it has a chip or fracture, and you inject it and the horse feels better, then you can end up doing more damage.” According to Dr. Moyer, some questions horse owners should ask themselves after talking to their veterinarians are, “Do I have the right diagnosis?” and “Do I understand the damage in the joint?”
Dr. Moyer points out that he has three things to think about with each case: 1) Is the horse lame? 2) Can the problem be treated, or should the horse be retired? 3) Is the owner willing and able to pay for the treatment?
Early signs of joint disease can be subtle, so owners must carefully monitor their horses for signs of joint swelling, heat, lameness or reduced ability to perform. Sometimes, by the time symptoms are noticed, damage may have already started.
Just as with people, in some cases the joints are simply beyond repair, and a career change may be necessary. For instance, a 20-year-old show jumper or eventer may need to compete only at the lower levels, over smaller fences.
What Are They Putting in There?
Acting similarly to the grease around ball bearings, joints are lubricated via synovial fluid. It is normally clear, pale yellow and viscous; in the face of joint damage it tends to lose viscosity—it becomes watery and is not as efficient.
“For therapeutic reasons, joints that have experienced wear and tear can be injected with a variety of medications that help them heal and remain flexible. This can prolong the usefulness of the horse,” Dr. Moyer says. There is a long list of possible medications to inject; what is used depends on the diagnosis.
In cases of arthritic changes, corticosteroids can offer pain relief and reduced inflammation. “Injecting [corticosteroids] directly into the joint as opposed to intravenously, or systemically, is much more profound,” Dr. Moyer says.
He explains that in the joint, inflammation can release all sorts of substances that can damage the cartilage and joint capsule. “In some cases, decreasing inflammation has a long-term beneficial effect because inflammation itself can be damaging. That’s why it is important to look at what is going on in the joint before you inject it.”
There are options for steroids, some long-acting, some short-acting. Short-acting steroids provide results that are likely to be seen in about 12 hours rather than a couple of weeks. Dr. Moyer says that long-acting steroids work similarly to time-release drugs in humans, providing relief over an extended period of time.
Dr. Daniel warns, “The downside is that sometimes people overuse steroids. They can be extremely beneficial if used properly, but they can be detrimental if used improperly. They are often misunderstood—it’s not that your horse will never be the same again because you have put steroids in a joint.”
Sodium hyaluronate, often called hyaluronic acid (HA), helps restore the function of the naturally occurring hyaluronic acid within the joint to improve the lubrication, stimulate natural production of HA and generally improve the synovial fluid. Injectable forms of varying molecular weights exist and have been demonstrated to have a positive effect in reducing the pain of arthritis. Also, HA is often used in conjunction with steroids. Oral forms of HA are also available on the consumer market, but their effectiveness is still being researched.
Adequan I.A. (polysulfated glycosaminoglycan) is an additional option, available for the treatment of non-infective joint disease in the carpal (knee) joint.
Joint injections are not without risk, including:
Any time you insert a needle into the body there is the potential to introduce bacteria, which can lead to infection. With proper handling and technique, and thorough preparation of the limb, the risk of infection can be minimized to a large degree. Yet even under the best of conditions, there is always some risk of infection following a joint injection. Symptoms of infection include heat, swelling and tenderness around the joint, and a reluctance to use the joint normally. Despite prompt treatment with antibiotics, once a joint infection is established, extensive destruction of the articular cartilage may still occur, resulting in debilitating lameness or permanent loss of use. If you have an infection there can be some time delay, and the onset of symptoms can be rapid and severe. Contact your veterinarian immediately if your horse shows any signs of infection.
Injecting corticosteroids into a damaged joint can help reduce inflammation and relieve pain, but then the joint is more at risk for re-injury when the horse returns to work.
In very rare instances, a needle can break. Though it sounds horrendous, the chances of this happening are slim. Dr. Moyer explains that this used to be a more common occurrence when needles were made of stainless steel and were brittle. Now they are made of alloys and are more flexible, thus less likely to break. “It’s been years since I’ve heard of it, but the potential is always there, so we have to mention it,” he says.
Adverse Reaction to the Chemicals
Rarely, some horses react adversely to medication, the same way some people react to a flu shot. Any adverse reaction should be treated as an emergency.
There is a long-term risk of corticosteroids causing cartilage breakdown. This depends on the individual horse: how much damage there was to begin with and how much joint stress the horse will continue to endure.
While corticosteroids are very useful in treating joint disease, some vets think that in certain instances steroids, especially triamcinolone, can contribute to the onset of laminitis or founder. Sticking to a small dose and regular schedule, and using steroids only when truly necessary, should help reduce this possible risk.
Following an injection, a return to work depends on the joint involved. “The ivory tower approach is extended lay-up, but we don’t find that necessary,” Dr. Daniel says. “Nobody is wrong here, but we give the horses 24 hours of stall rest and then two to three days of turnout, then they can start light flat work. We are often dealing with horses that can’t take extended time off. That has forced our hand at minimal lay-up, but it seems to work well.”
Often, older horses have a lot of lumps and bumps to show for their years. If a joint has been swollen for a long time, the vet will need to remove the fluid, inject the joint, and then the horse will probably need a couple of weeks off.
Take Home Message
While not for every horse, and not without risk, joint therapy can be a tool for prolonging your horse’s athletic usefulness. But Dr. Moyer warns that he never uses therapeutic joint injections as a preventive measure where there is no existing problem. “I won’t be sticking needles into [a joint] because it might have a problem,” he says. “Every time someone sticks a needle into a joint, there is a risk.”
Success with joint injections has many variables. Everyone has different goals: One owner may be happy if a horse can walk across the paddock comfortably, while another will rate success by how an athlete can perform. “One of the things you have to ask yourself is, ‘How am I defining success?’ ” Dr. Moyer points out. “Was your horse lame and now he isn’t? Was he lame and then sound, and then even worse than ever? The result is going to vary with the severity of the problem and what is being expected of the horse. Dressage is more forgiving than steeplechasing, for example.” In the end, each individual responds differently to the various treatments, so tailoring a program to each horse is essential to success.
Amber Heintzberger is a freelance equine journalist based in South Carolina. An active member of the horse community, she competes at the Preliminary level of eventing.
This article originally appeared in the February 2006 issue of Horse Illustrated. Click here to subscribe.
To Whom It May Concern:
Your article on joint injections for senior horses seems to offer as many, or more, risks than rewards. It seems like it would be a pain for there to be as many side affects as there are cures.
This probably works great; I’m not saying it doesn’t, just that people won’t be as eager to buy this when they realize it might do more bad then good; if they are unlucky. There are many risks, including getting the needle caught in the joint, an adverse reaction to the chemicals, laminitis, and joint degeneration, just to name a few. This article says; ‘Injecting corticosteroids into a damaged joint can help reduce inflammation and relieve pain, but then the joint is more at risk for re-injury when the horse returns to work.’ So then isn’t it better for the horse to not get this and retire early? Or should the owner have this done and keep doing it regularly so that it does not get re-injured? I have a friend that is interested in getting a joint injection for her horse, but she also wants to keep working her. Should she do that? And how often should the joints be treated then?
This seems like a great way to get horses back on their working routine, it just seems that your article on joint injections for senior horses seems to offer as many, or more, risks than rewards.
Thanks for the interesting article. Although I have never had a situation that I have had to consider using such an injection it’s very good info to keep in mind. I hope I never have to dig this out of my memory to use!!!
I like how you told us the risks in using joint injection. I believe that a lot of people are in such a hurry to ‘fix’ their horse that they take any solution thrown at them. Not all look at the risks in putting a needle into the joint of such a large animal. I am writing an essay for my class argueing the pro’s and con’s of joint injections and this article really helped me understand more then I could of hoped for. thank you
I might have to do more research, but I would rather feed supplements.
I found this article very interesting. My horse was injected today in both hocks – one with steroids and HA and the other just with steroids.
Your article echoed everything my vet had told me.
Just be careful. My gelding had both hocks injected 4/13/10, and we followed the rest/light moving instructions carefully. He seemed to be OK and was ridden lightly in 2 weeks. On 5/3/10 he was lame and has had abscesses on three different feet over the next several months. He displays other signs of founder (tender front feet, reluctance to move downhill, a dish in the RF), but the vet thinks not and denies connection to the injections. It now takes 4G(!) bute to make him comfortable for jogging on a soft flat surface, and I may have to put him down. Another friend had the same experience (another vet) and lost her show horse.
I liked the article, but need more info. Several years ago had my saddlebred in training. He received injections in either his shoulders or withers. This loosened and freed up his front end. Was I dreaming this or do vets still do it.
I have a 26 year old Western pleasure gelding who is still in amazing shape. I have owned him for 17 years. He has never been abused or pushed, but he has however developed arthritis in his left hock. I injected him for the first time last year with amazing results. After two weeks lameness was gone and he was much more comfortable. I don’t think this should be a first resort for anyone, but it has made my boys life much more enjoyable and comfortable in his golden years. He was able to return to the show pen and is still being lighty shown by my 9 year old daughter.
my horse was injected 2 wks ago told to ride her as usual all the time even though she had previously gone down on roads did it again today wont be riding her again very upset.