Arthritis is a major problem for horses. The size of the horse joint supplement industry reflects this. There are at least 50 different products out there-probably more. Supplements, however, are not magic bullets for horses. It's important to understand how joint problems get started in your horse, what you can do to prevent or slow their progress and how to manage joints in a kind and comprehensive way.
A number of things factor into the arthritis equation:
Conformation. You really can't do anything about your horse's conformation, but it is important when buying a horse and understanding what types of activities he may or may not be able to do without running into joint problems. We can't go into all the possible conformation faults here that affect horses, but some common examples are sickle hocks and offset cannon bones.
When viewed from the side, the cannon bone of a sickle-hocked horse slopes forward, rather than being perpendicular to the ground. This puts the horse's hoof and ankle, his base of support and major shock-absorbing region, too far forward, which increases the forces delivered to the hock. In addition, the forces along the front of the hock, where arthritic changes occur, increase. A sickle-hocked horse has a higher risk of developing arthritic hocks.
In the front legs, offset cannon bones mean that, when viewed from the front, the cannon bone is not positioned squarely under the knee but is shifted to the outside. This leaves the inside of the knee joint, where much of the weight is concentrated, without adequate support and is a risk factor for arthritis.
- Keep hooves well trimmed and balanced to prevent arthritis.
- Use exercise to keep joints mobile while being careful not to overstress arthritic joints.
- Slow arthritic progression by supplementing before extensive joint changes have occurred.
- Feed a loading dose of your chosen supplement until maximum improvement occurs.
- After the initial loading period, Experiment with lower doses to find the level that maintains the positive effect.
Trimming and shoeing. Although "corrective" shoeing used to be all the rage and is still practiced to some extent, the truth is that trimming, balancing and exotic shoes can't really fix anything. When there is pain relief, it is temporary and often comes at a high price.
The feet are the horse's base of support. It's important to avoid overstressing arthritic joints and prevent arthritis from developing by making absolutely sure the horse's feet are kept well trimmed and meticulously balanced. This is true regardless of whether the horse is shod or barefoot.
Imagine how uncomfortable, tiring and eventually painful it would be to try to move around all day with a lift under only half of your heel. Pain would develop from your heel to your hip. The severity of the problem will depend on how bad the imbalance is. But even slight imbalances change the way the joints are loaded and can cause trouble over time.
Stand in front of the horse and picture what happens if you put a piece of wood under either the inside or outside of the foot. On the side that is higher, the bones are forced closer together than normal, while on the lower side the joint capsule and ligaments are stretched. Both can cause inflammation and eventually arthritis.
To understand what happens to a horse with overly long toes and under-run heels, try walking with a sandal taped to your foot so that it extends an inch or so in front of your toes, leaving the back inch or more of your heel hanging over the back end of the sandal. You'll feel pressure across the heel at the edge of the sandal (translating to navicular-area irritation in the horse) and excessive pull/stretch in your Achilles tendon. You'll also feel ankle strain.
In a horse, heels that are too short or too high may cause abnormal forces in one of the most common and difficult-to-treat sites for arthritis-the coffin joint (articular ringbone).
Exercise. Exercise is blamed for causing arthritis, but the truth is that exercise is essential for healthy joints. Joint cartilage has no blood supply. It is nourished and cleaned by joint fluid being compressed out of the cartilage when the horse moves, fresh fluid flowing in when the joint is not bearing weight. Exercise also stimulates cartilage to become stronger in areas that are being stressed. It strengthens the ligaments between bones, holding them in alignment. Controlled, sane exercise is very important for the health of arthritic joints and should be part of the treatment plan.
On the other hand, extremes of exercise, such as work at speed, sharp turns, exaggerated gaits, or years of jumping, do stress the joints. Avoiding arthritis in these hard-working athletes involves always working the horse within the limits of his conditioning and conformation, plus constant surveillance for early indicators of a problem. Personality changes, changes in gait, stiffness and any obvious joint swelling, heat or pain are all signs that something might be wrong.
Weight. Although often overlooked, a horse's weight puts considerable stress on the joints. Avoiding obesity greatly reduces the load the joints have to carry. It's one risk factor that is 100% under our control. If the horse is already arthritic, weight control should be an integral part of the treatment plan.
Hands-on care. While there is an important place for supplements and drugs, don't overlook the value of hands-on care. It doesn't have to involve expensive therapy, equipment or wraps. Two of your most potent tools are heat and cold.
Horses with arthritic changes who tend to get stiff (such as standing overnight or in cold weather) can benefit greatly from inexpensive Neoprene wraps, or even regular stall bandages for stiff fetlocks. These keep the area warm and relieve stiffness. A brisk rub with a warming liniment before exercise also helps loosen stiff joints.
Cold, on the other hand, is the best inflammation buster out there and also puts the brakes on destructive enzymes. Horses suffering painful flare-ups of arthritis can be brought under control quickly by aggressive icing. Routinely icing old problem areas after exercise is a good way to avoid those painful flare-ups in the first place. You may want to invest in gel pack ice boots, or you can just use crushed ice packed into Ziploc bags and secured to the leg.
When Joint Supplements Need a Boost
Joint supplements target cartilage breakdown and inflammatory responses in general. This makes them of some use in almost all horses, but there's more to arthritis, especially advanced arthritis, that can severely limit how well the horse responds. Limited response can be expected in the following circumstances:
- Horses with stresses on the joints caused by poor conformation or improperly trimmed and balanced feet.
- Horses with structural instability in the joint. This includes tears in the joint capsule, the ligaments supporting the sides of the joints, small ligaments between bones in the hock or knee joint, and damage to the menisci or the "X" shaped internal stabilizing cruciate ligaments in the stifle.
- Joints where cartilage loss is so extensive that the joint space is abnormally narrow on X-rays.
- Joints with development of osteophytes/bone spurs (commonly seen in the hock and fetlock joints), or with diffuse proliferation of bone (e.g., ringbone in the coffin or pastern joint).
For as long as joint supplements have been around, you'd think we would have a lot of good scientific information available about them, but that's just not the case. Even in the human medicine field, where more research money is available, we still have gaps in information. In horses, only two products have actually been tested by formal scientific studies-Nutramax's Cosequin™ and Equine America's Corta-Flx™.
Joint supplements range from single ingredient products to "combination products," some of which contain almost 30. There are two general classes of ingredients: those that are components of joint fluid and joint cartilage or are involved in the metabolism of those tissues; and ingredients added to control pain or inflammation. Costs per day run from under $1 to more than $5 a day at higher ends of dosing.
Glucosamine (sulfate or hydrochloride) and chondroitin sulfate were the first components to be used in joint supplements, and are compounds naturally found in the joints. Hyaluronic acid (also used as an injectable-see sidebar on page 15) is the most recent addition to oral supplements and is also a natural component in joints. Some ingredient lists may show "cartilage." This is a source of chondroitin. Collagen is also sometimes added, the basic protein building block for cartilage, bone and all connective tissues.
Also on the list of ingredients important to building and maintaining joint tissues are vitamin C and trace minerals like manganese and copper. In addition to providing "food" for building and repairing the joint, these ingredients have an anti-inflammatory effect, probably by tying up destructive enzymes that would otherwise be attacking the cartilage.
Ingredients targeting pain and inflammatory responses include herbals such as tumeric, curcumin, devil's claw, cat's claw, boswellia, white willow and yucca. Other ingredients in this category are MSM (methylsulfonylmethane), anti-inflammatory fatty acids, grapeseed extract and other plants/fruits with high antioxidant activity.
If you had a major headache, would you expect one baby aspirin to take care of it? If you have an infection, would you expect to be able to skip doses or cut the dose of antibiotics in half and still have it control the infection? Of course not. It's no different for joint supplement ingredients.
Dosages in individual products vary tremendously, from very generous to so low that about the only reason to include the ingredient is so that it can appear on the label. Below is a list of the major joint supplement ingredients, and usual effective doses.
Glucosamine Sulfate or Glucosamine Hydrochloride
- Loading dose, dose for horses in regular work: 10,000 mg (10 grams) per day
- Maintenance dose when not in regular work, dose in combination products: 5,000 to 7,500 mg (5 to 7.5 grams) per day
- Loading dose, dose for horses in regular work: 3,500 to 5,000 mg (3.5 to 5.0 grams) per day
- Maintenance dose when not in regular work, dose in combination products: 1,750 to 2,000 mg (1.75 to 2.0 grams) per day
- Single ingredient product, acute conditions: 100+ mg per day
- As part of a combination product: 20 mg per day
What to Expect
We still don't have a solid grip on what to expect from these products. Can they be used to prevent arthritis? Do they actually help healing? What types of problems are best treated this way, and at what stages?
We don't know if feeding joint supplements will prevent or delay arthritis, but there are many people who use them for exactly that reason. And whether or not they actually help heal diseased joints has been debated as well.
Dr. Jason Theodosakis' 1997 book, The Arthritis Cure, claims that supplements do work. And some recent reports seems to support that assertion. A study published in March of this year in the journal Physiological Research created cartilage defects in rabbit joints and then compared healing in unsupplemented rabbits and in rabbits given a glucosamine/chondroitin/antioxidant supplement. The supplemented group had less joint swelling, better quality joint fluid and superior healing.
However, most studies in naturally occurring arthritis have been done with people. The majority of these do show relief of pain, better movement and, in some cases, a slowing of arthritic progression. It is generally agreed that the sooner supplements are started, the better the result will be.
The same holds true for horses. Best results will be seen when the problem is identified before extensive joint changes have occurred, and also when careful attention is paid to meticulous foot balance, regular but controlled exercise (the equivalent of physical therapy for your horse), and local joint care.
Selecting a Product
Liquid and gel joint supplements are more expensive and have a shorter shelf life, but tend to work more quickly and sometimes at lower dosages than powders. The more ingredients a product has, the higher the price tends to be. Potency/dose also influences price, so be sure to check the dosages of ingredients against the guidelines in the dosing sidebar above. Older or relatively inactive horses may respond well at lower dosages than horses being ridden regularly.
If you are using a joint supplement for the first time, start with one based on glucosamine or glucosamine and chondroitin in combination. Feed enough to provide the loading dose on the chart for seven days.
The first sign of a positive response is usually an improvement in how freely the horse moves overall. You may see better stride length, a more relaxed way of going, and more fluid movement. Any swelling or heat in problem joints should begin to improve.
If you are not seeing any difference after seven days, 10 at the most, try adding hyaluronic acid or MSM to the program, or switch to another product that contains one or both of these ingredients. If you are dealing with a long-standing problem, and the horse really only seems to respond maximally when given pain-relieving drugs like phenylbutazone, adding devil's claw (or using a combination product that contains it) may be your best choice.
Once you have found a product that works for your horse, stay with the loading dose until no further improvements are seen. At that point, you can try reducing the dose to see if you can maintain those improvements on a lower dose. However, while most products talk about both loading and maintenance doses, in reality many horses need to stay on the higher doses to get good relief.