Key Takeaways

• Osteoarthritis accounts for an estimated 60% of equine lameness cases, making it the leading cause of unsoundness in horses¹.

• Joint injections and joint supplements do not do the same job. They work on different timelines and address different needs.

• Injections treat acutely. A well-formulated supplement program supports the joint day in and day out.

• Building blocks like glucosamine, chondroitin, and hyaluronic acid are only part of the picture. Supporting the body's inflammatory response is equally important.

• Joint health is a whole-horse issue: body condition, conditioning, hoof care, and gut health all play a role.

• The earlier you start, the better.

Quick Answer

Joint injections and joint supplements are not interchangeable. Injections address acute injury or inflammation directly inside the joint. Supplements, when properly formulated and dosaged, support the joint's daily environment: the cartilage, the inflammatory response, and the systemic conditions that determine how a joint holds up over time. For horses already receiving injections, a full-spectrum supplement fills the gaps that injections are not designed to address. As Dr. Rob Franklin, board-certified equine internal medicine specialist, puts it: they go hand in glove.

Osteoarthritis Is Not Just an Old Horse Problem

Every horse has stress on its joints - from standing in the stall to every run, stop, and turn. 

Joint issues rarely announce themselves. They build quietly through wear, through inflammation, through stress that compounds over time. By the time something is visible, the problem has usually been developing for a while.

As Dr. Keith Latson, equine orthopedic specialist, describes it: "There is a quiet whisper within the joint that riders will feel and describe as a horse just not striding out, or it's taking longer to warm up, some of those subtle signs before we really start to see the clinical signs of heat or pain or lameness."

Osteoarthritis is the leading cause of lameness in horses, accounting for an estimated 60% of lameness cases in the U.S. horse population.¹ It is not a condition that only affects older horses in retirement. It shows up in young performance horses. It shows up in horses that look and move well, right up until they don't.

When we ignore those early whispers, Dr. Latson notes they become compounded. "Osteoarthritis is created by subtle change over time. If we're asking an inflamed joint to do that over and over, it's just not able to repair and keep up with the demands on that joint."

The way you manage your horse every day has a direct impact on how those joints hold up over time.

Think About the Whole Joint, Not Just the Cartilage

One of the most common mistakes in joint management is narrowing focus to cartilage alone.

"When we think about joint disease, we should think about it as the whole joint, not just the cartilage," Dr. Latson explains. "We've got to think about the synovium, the lining of the joint itself, the joint capsule, the cartilage within the joint, the fluid within the joint. Each of those components is susceptible to inflammation."

Dr. Rob Franklin, equine internal medicine specialist, adds another layer: joint inflammation is often a reflection of whole-body inflammation, not just a local problem. "There are some horses that have a lot of inflammation in their body and that can be due to illness, it can be due to disease, it can be due to nutrition, it can be due to environment, and it can also be due to injury. The more joints affected, the more you start to think about whole body versus one acutely affected joint."

Understanding that distinction changes how you approach the program.

What Injections Do and What They Don't

Joint injections are an important tool. For acute inflammation, an injury, or a flare from ongoing wear and tear, they can provide targeted, meaningful relief directly at the source.

But injections treat the moment. They are not designed to provide daily, ongoing support to the joint environment. They wear off. They need to be repeated. And depending on the substances used and the frequency, there are considerations around long-term cartilage health that your veterinarian can speak to.

What injections do not do is address the daily inflammatory environment of the joint, support cartilage integrity over time, or manage the systemic factors including gut health that influence how inflammation originates and travels through the body.

That is where a well-formulated supplement fits.

What a Supplement Does

A joint supplement, when vet-formulated and dosed correctly, supports the joint from the inside out every single day.

Building blocks like glucosamine, chondroitin sulfate, and hyaluronic acid provide raw materials the joint uses to maintain cartilage structure and synovial fluid quality. In vitro studies have shown that glucosamine and chondroitin sulfate can reduce cartilage degradation and have anti-inflammatory effects on chondrocytes.² One published field study followed 10 horses over eight years and found that consistent glucosamine and chondroitin supplementation was associated with a meaningful reduction in the frequency of joint injections needed over the course of the study.

But building blocks alone are not the whole picture.

Dr. Franklin is direct on this point: "The idea of just providing the body a set of Legos to repair itself is a bit short-sighted. We really need to call out the things that we can do to really help that joint stay healthy. The more time that a horse has inflammation in his joint, the more that arthritis is going to manifest and it's going to be a permanent change."

Most basic formulas do not address inflammation. Four Sixes Joint Health Pellets were formulated to cover the full picture. Building blocks including glucosamine, chondroitin, and hyaluronic acid, alongside Boswellia serrata, which has been shown in research to inhibit pro-inflammatory pathways including 5-lipoxygenase, with effects on cytokines linked to cartilage destruction.³ The formula also includes Cetyl-M, a fatty acid Dr. Franklin describes as something that "will congregate in the joint and then will help to reduce the amount of inflammation that's in that joint," and a targeted postbiotic designed to support the gut-joint inflammatory connection.

The Gut-Joint Connection Most People Miss

One of the most overlooked drivers of joint inflammation in performance horses is the gut.

Dr. Franklin explains: "The amount of inflammation that shows up in a joint is largely governed by the inflammation that's going on in the gut. So if we can really help keep that gut stabilized, then the amount of inflammation that overflows from that gut will be very low and won't end up in the joint."

This is not theoretical. Dr. Latson points to specific research on the postbiotic in the Four Sixes formula: "Research horses had something injected into their joints that causes inflammation experimentally. The horses that were getting the postbiotic had significantly decreased inflammatory mediators in their joints. They actually demonstrated that direct gut-joint axis and how correcting nutrition and supplementing nutrition can have such a positive effect on joint health."⁴

Dr. Franklin puts it plainly: "It's widely unknown amongst most horse people how important it is for us to minimize the inflammation in the gut in order to minimize the inflammation in the joint."

How to Choose a Joint Supplement That Actually Works

Not all joint supplements are equal, and the differences matter.

Dr. Franklin's first filter is trust in the brand and the people behind it. "There are just so many charlatans out there that we recognize as veterinarians. People go into feed stores and they're inundated with choices and it's very difficult to look at that package and to know and trust what's in it."

The second filter is whether the formula takes a multimodal approach. "Any product that's just providing building blocks is probably not going to have a tremendous effect on that horse. Having that multimodal would include not only the building blocks, but also as many ways as we can specifically minimize joint inflammation as possible."

The third is dosage. Dr. Franklin describes what he calls label dressing: "Someone may put a tiny amount of hyaluronic acid in something and say this has joint health benefits because it has hyaluronic acid. It may be in just such an unmeaningful concentration that there's just really no hope that you're going to get a response from feeding that."

Dr. Latson adds a practical test: "If it's a really tiny scoop and it's got a hundred ingredients in it, you can feel pretty sure that for a thousand to twelve hundred pound horse, it's probably label dressing."

Management Tips That Actually Protect Joints Long-Term

These are not quick fixes. They are the daily decisions that determine how your horse's joints hold up over a career.

1. Manage Body Condition

Extra weight adds direct, daily stress to joints, tendons, and ligaments. Even modest excess body condition increases the mechanical load on joint structures with every step. Take an honest look at your horse. The goal is athletic and appropriate for the workload.

2. Do Not Skip Conditioning

A horse that is not conditioned for the work being asked of it is a horse at risk. The body adapts to progressive, consistent demands. Joints, tendons, ligaments, and musculature all become more resilient with appropriate loading over time. Cross-training reduces the repetitive strain of single-discipline movement patterns. Conditioning is joint protection.

3. Use a Full-Spectrum Supplement

Most owners believe they have joint health covered when they have a supplement in the feed room. But many products only address one piece of the puzzle. Building blocks without inflammatory support leaves the joint environment unaddressed. A full-spectrum approach covers cartilage building blocks, inflammatory response support, and the gut-joint connection.

4. Address the Gut-Joint Connection

Research has established a meaningful connection between gut microbiome disruption and systemic inflammatory responses that affect joints.⁴ A horse's gut is where much of the body's immune signaling originates. When that system is under stress from hauling, competition, feed changes, or NSAID use, it can influence the inflammatory environment of the joints. 

5. Pay Attention to Feet

No foot, no horse. That saying exists for a reason. Hoof balance and proper trimming directly affect how concussive forces travel up through the limb and into the joints. Uneven wear, imbalanced feet, and inconsistent farrier care all place added strain on joint structures with every stride. A coordinated approach between your veterinarian and farrier matters more than most people realize.

6. Know Your Horse's Baseline

Your horse cannot tell you what hurts. Running your hands down their legs after work, knowing what heat, filling, or sensitivity feels like in their normal state, that is how you catch something early. Puffiness, stiffness at the start of a session, or a subtle change in the way they load a limb is information. Treat it that way. (Check out the leg exam walk through with Dr. Keith Latson here!)

7. Work With Your Veterinarian

Every horse is different. If your horse is receiving injections or other therapies, build a program around that individual horse with your vet's input. This is not a one-size-fits-all situation. A veterinarian who knows your horse's history and work demands is your most valuable asset in building a soundness program that holds up over time.

Actionable Checklist: Building a Joint Health Program

• ✓ Start supplementation before problems develop

• ✓ Choose a formula that covers building blocks, inflammatory response support, and the gut-joint connection

• ✓ Assess body condition honestly and adjust feeding and exercise accordingly

• ✓ Build conditioning progressively. Workload should match fitness

• ✓ Schedule regular veterinary exams, not just when something goes wrong

• ✓ Get familiar with your horse's legs. Know the baseline

• ✓ Coordinate with your veterinarian and farrier on hoof balance and shoeing adjustments

• ✓ Support gut health year-round, especially during hauling, competition, and NSAID use

• ✓ Increase supplement support during periods of heavier demand

Frequently Asked Questions

Does a supplement still help if my horse is already being injected? Yes. Injections and supplements do not overlap. Injections address acute inflammation at the joint level. A supplement supports the daily environment those joints live in: cartilage maintenance, inflammatory response, and the systemic conditions that affect how the joint holds up between injection cycles. They work better together than either does alone.

How long before I see results from a joint supplement? Oral joint supplements work gradually. Dr. Latson describes it this way: "We may see an effect in the first 14 to 21 days from the inflammation starting to quiet down. But where we start to see the real benefits, where the riders start to feel the real benefits with the horses having the propulsion from behind that they used to, we may not see that for 30 to 60 days if we're looking at supplementation alone." Start early and stay consistent.

When should I start and stop supplementing? Dr. Franklin is clear: "As soon as the horse is in training, it's started on joint supplements, it remains on joint supplements while it's in training." For horses with chronic joint issues, he recommends year-round supplementation regardless of activity level, because inflammation continues even when the horse is not working. "Once that inflammation starts, it starts the process of arthritis, and that is a progressive condition."

What is the gut-joint connection? The gut is where a significant portion of the body's immune and inflammatory signaling originates. When gut health is disrupted, that signaling can ripple systemically including to joint tissues. Research has demonstrated a connection between gut microbiome disruption and inflammatory responses associated with osteoarthritis and joint disease. Supporting the gut is part of supporting the joint.

What makes Four Sixes Joint Health Pellets different from other joint supplements? Most joint supplements provide building blocks: glucosamine, chondroitin, hyaluronic acid. The Four Sixes formula goes further by including Boswellia serrata and Cetyl-M to support the inflammatory response at the joint level, and a targeted postbiotic to address the gut-joint inflammatory connection. The goal, as Dr. Franklin describes it, is a multimodal approach. "Don't settle for just building blocks in cartilage and the joint fluid. Look for things that minimize inflammation and look for things that help support the gut-joint axis."

What signs tell me my horse's joints need more support? Subtle stiffness at the start of a ride that works off, reluctance to engage, heat or filling in joints after work, changes in willingness or way of going. These are early signals worth paying attention to. Do not wait for obvious lameness. By the time a horse is visibly lame, the problem has usually been building for a while.

Should I change the dose during heavier competition seasons? Yes. Many horses do well at a maintenance dose during lighter work and benefit from increased dosing during peak training, hauling periods, or competitive seasons.

The Takeaway

Joint injections have their place. They are not the whole program.

Whether you are supporting a horse that is already being injected or working to protect joints before problems develop, daily support is what determines the long term.

Learn more about joint health here. 

We focus on the whole horse. The science. What works and stands the test of time, not chasing trends or quick fixes.

Formulated by veterinarians. Trusted on the ranch and in the arena. Built for horses that work.

The 6666 Equine Supplements Team

 

References

1. McIlwraith CW, Frisbie DD, Kawcak CE. The horse as a model of naturally occurring osteoarthritis. Bone Joint Res. 2012;1(11):297-309.

2. van de Water E, Oosterlinck M, Dumoulin M, et al. The preventive effects of two nutraceuticals on experimentally induced acute synovitis. Equine Vet J. 2017;49(4):532-538.

3. Beghelli D, Zallocco L, Angeloni C, et al. Dietary supplementation with Boswellia serrata, Verbascum thapsus, and Curcuma longa in show jumping horses. Life (Basel). 2023;13(3):750.

4. Favazzo LJ, Hendesi H, Villani DA, et al. The gut microbiome-joint connection: implications in osteoarthritis. Curr Opin Rheumatol. 2020;32(1):92-101.