Ringbone in Horses: High vs Low, Signs, Treatment and Long-Term Outlook

What Ringbone Actually Is

Arthritis below the fetlock, named for the ring of bone it can leave around the pastern.

Below the fetlock, a horse's leg has three bones: the long pastern bone (P1), the short pastern bone (P2) and the coffin bone (P3) inside the hoof. Between them sit two joints. The pastern joint, which vets call the proximal interphalangeal or PIP joint, joins P1 and P2. The coffin joint, the distal interphalangeal or DIP joint, joins P2 and the coffin bone, below the coronary band.

Ringbone is osteoarthritis of either joint. Cartilage wears, the joint gets inflamed, and the body lays down new bone around the joint margins as it tries to stabilise it. In bad cases that new bone can be felt as a firm ring around the pastern, which is where the name comes from. US Equestrian, with Dr. Liz Barrett of Hagyard Equine Medical Institute describes it as a degenerative disease of the pastern and coffin joints that affects horses of every breed, age and job.

It is a common reason for lameness in the pastern. A 2026 study of 58 horses with pastern-joint arthritis found that almost half (46.7% of limbs) also had damage to the straight sesamoidean ligament behind the pastern, and the worse the arthritis, the worse the ligament tended to be (Barton et al., Equine Vet J 2026). Ringbone is rarely just a bone problem.

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High vs Low, Articular vs Periarticular

Two questions decide almost everything: which joint, and does the new bone involve the joint surface?

The high-motion vs low-motion distinction and the aims of fusion come from US Equestrian, with Dr. Liz Barrett of Hagyard Equine Medical Institute.

Most horses can be described on both axes. "Articular high ringbone" is the classic progressive form that ends up being fused. "Periarticular high ringbone" may cause lameness while the new bone is forming and then quieten down. Ask your vet to describe your horse's X-rays in exactly these terms, because they predict what will happen next far better than the word "ringbone" alone.

Ringbone by the Numbers

Sources: de Souza et al., J Equine Vet Sci 2023 · Herthel et al., Equine Vet J 2016 · Hicks et al., Equine Vet J 2021 · Caston et al., Equine Vet J 2013 · Sakai et al., JAVMA 2018 · Barton et al., Equine Vet J 2026 · van Veggel et al., JAVMA 2026

The Signs of Ringbone

It usually starts as a lameness you can't quite pin down.

None of these is specific to ringbone. Navicular syndrome, coffin-bone problems, sole bruising, abscesses and laminitis all cause lameness in the same area, so a bony lump or a sore front leg is a reason to call your vet, not a diagnosis. If your vet is weighing up the foot as well, our navicular disease guide and laminitis guide cover the look-alikes.

What Causes Ringbone

Wear, impact, injury and how the horse is built, usually in some combination.

• Conformation. Upright pasterns concentrate concussion on the joints; long, sloping pasterns strain the ligaments around them. Toe-in, toe-out and offset limbs load one side of the joint more than the other.
• Hoof balance and trimming. A long toe, low heel or medial-lateral imbalance changes how force passes through the pastern and coffin joints at every step.
• Concussion and workload. Repetitive work on hard ground, and sports with sudden stops, pivots and turns, put repeated stress on low pastern structures. Older horses have simply carried more miles.
• Injury. A fall, a kick, a wire cut, a fracture of the pastern bones or a ligament strain can all start new bone formation. Dr. Barrett lists injury, infection and normal wear and tear as the main causes.
• Developmental disease. Osteochondrosis and bone cysts in young horses can damage the joint early and set up arthritis later.
• Soft-tissue damage alongside it. The 2026 Barton study found straight sesamoidean ligament injury in almost half the limbs with pastern arthritis, which suggests instability and ligament damage often travel with the bone changes.

You can't change conformation, but you can control trimming intervals, footing, body weight and how a horse is conditioned before it is asked for hard work. Those are the levers owners actually have.

How Vets Diagnose Ringbone

Find where the lameness is coming from first, then picture it.

1. History and lameness exam. Your vet watches the horse move straight and on circles, on hard and soft ground, and palpates the pastern for heat, swelling and bone.
2. Flexion tests. Holding the lower leg flexed and then trotting off can make a painful joint more obvious.
3. Nerve and joint blocks. Local anaesthetic is used to numb the leg in stages. Dr. Barrett describes starting by blocking the foot, then working up to the fetlock. If the horse goes sound after a particular block, the pain is in that region.
4. Radiographs. X-rays confirm ringbone, show whether it is high or low and whether it is articular, and grade how far it has gone. Early cases can look normal, so a repeat film weeks later is sometimes needed.
5. Ultrasound or MRI. Used to look at the ligaments around the pastern and at cartilage in the coffin joint. Standing MRI can show coffin-joint cartilage loss that X-rays miss; van Veggel's 2026 study found a joint-width measurement under 3 mm pointed to cartilage damage.

If you are buying a horse, this is where a pre-purchase exam earns its fee. Dr. Barrett recommends discussing any sign of ringbone on pre-purchase films with your vet before going ahead.

Treatment Options, Side by Side

Start simple, step up only when the horse needs it. Here is what each option involves and how strong the evidence is.

Our banamine guide covers flunixin for short-term pain: Banamine for horses.

Two honest caveats about that table. First, almost nothing in it was tested specifically in horses with ringbone except fusion. The injection and biologic data come mostly from other joints or from experimental models. Second, most of the fusion studies are retrospective case series from referral hospitals. They are the best evidence we have, but they are not randomised trials.

Pastern Fusion: What the Primary Studies Actually Found

The option that gives high ringbone a real long-term answer, and its honest numbers.

The logic of fusion is simple. The pastern joint only moves a little, so if the two bones grow into one, the painful joint is gone and most horses can still move well. The aim is a pain-free, fused pastern. Here is what each study we read found:

Sources: de Souza et al., J Equine Vet Sci 2023 · Herthel et al., Equine Vet J 2016 · Sakai et al., JAVMA 2018 · Hicks et al., Equine Vet J 2021 · Heaton et al., VCOT 2019 · Caston et al., Equine Vet J 2013

What stands out across these papers:

• Hind legs do better than front legs. The Herthel gap (73% vs 25% in athletes) is the single biggest difference owners should know about, and Hicks also saw more hind-limb than forelimb successes (11 of 13 vs 12 of 15).
• Arthritis cases do better than fracture cases. Sakai found horses fused for reasons other than fracture were significantly more likely to return to their previous work, and the meta-analysis notes return to soundness may be lower for fractures.
• Recovery is long. Expect weeks in a cast or splint and months before riding: median 7 months in Sakai, 6.5 months in Heaton, and more than 12 months in six of the Hicks performance horses.
• Complications are real. Infection runs around 12% across studies, and Hicks reported support-limb laminitis in two horses. One later study of 54 fusions had an infection rate of only 3.7%, so surgeon and hospital matter.
• Chemical fusion is the budget option, not the equal option. Caston developed it because some owners couldn't afford surgery. Half the horses came sound, and recovery took longer. An experimental study in healthy joints found alcohol alone did not reliably fuse the joint, so results depend on case selection.

Can a Horse With Ringbone Be Ridden?

Often yes for high ringbone. Low ringbone is a harder conversation.

High ringbone. Many horses with mild or periarticular high ringbone stay in light to moderate work with pain management and good farrier care. When the joint is fused successfully, a return to riding is a realistic goal: 18 of 23 surviving horses in the Sakai study returned to their intended use, and in Herthel's study most Quarter Horses went back to Western performance work. Dr. Barrett makes the point that because the pastern is a low-motion joint, a horse with high ringbone has a better chance of being ridden after fusion.

Low ringbone. The coffin joint moves a great deal, so fusing it rarely gives back an athletic horse. In the van Veggel MRI study, 22 of 25 horses with coffin-joint cartilage loss did not return to performance. Many horses with low ringbone become comfortable pasture companions or very light trail horses, and that can be a good life.

How to ride a horse with ringbone. Keep work on forgiving, even footing. Avoid tight circles, sharp pivots and long sessions on hard ground. Warm up longer. Keep the trimming or shoeing interval tight so the toe never gets long. Watch for the day the horse is sorer, and back off. Your vet should set the ceiling.

How Long Can a Horse Live With Ringbone?

Ringbone affects comfort, not lifespan directly.

No study has measured how long horses with ringbone live, and anyone quoting a number is guessing. Ringbone is a joint disease, not a fatal one. Plenty of horses live into their twenties and beyond with it, especially high ringbone that is well managed or fused. The honest limit is quality of life: a horse that cannot be kept comfortable on any combination of treatment is the horse where the conversation changes. For context on what a normal span looks like, see our guide to how long horses live, and for the older horse, our senior horse guide.

Where Hemp Fits — and Where It Doesn't

We sell hemp oil for horses, so here is the honest version.

No study has tested CBD or hemp in horses with ringbone. Not ours, not anyone's. Hemp will not remove new bone, will not stop a joint from wearing, and is not a substitute for X-rays, joint injections, shoeing or fusion. If a product claims to fix ringbone, it is ahead of the evidence.

Here is the closest evidence. In a randomised study of 20 mature horses with mild joint osteoarthritis, horses given CBD oil alongside phenylbutazone had a median Horse Chronic Pain Scale score of 3, against 7 in horses on phenylbutazone alone, with lower heart and respiratory rates (Interlandi et al., Frontiers in Veterinary Science 2024). That is joint arthritis, the same disease process as ringbone, but it was a small trial, it did not look at pasterns specifically, and the CBD was given with bute, not instead of it. Our own equine formula was studied at Tarleton State University: a single serving lowered stereotypic stall behaviours compared with a control oil (Turner et al. 2021), and a dose study found no adverse effects at 0.3 or 0.6 mg/kg. That research was about behaviour and tolerability, not lameness. You can read what Tarleton measured.

So hemp's honest role for a horse with ringbone is as one part of a daily routine, alongside the treatment, farrier work and management your vet sets, to support comfort and normal movement. It has no role in the decision about injections or fusion, and you should never use it to delay a vet visit for a new lameness.

Using Hemp Alongside the Vet Plan

How much. One pump of our 5,000 mg oil is about 20 mg. The Tarleton studies used 0.3 to 0.6 mg/kg per serving. Start at the low end and stay there for a couple of weeks before deciding anything. Full chart in our horse dosing guide.

Ranges follow the 0.3–0.6 mg/kg range used in the Tarleton studies of our formula. A bottle holds about 250 pumps, or 3–4 weeks for an average horse at about 10 pumps a day.

How to give it. Pump it onto the horse's usual feed once a day, at the same time each day, so it becomes part of the routine. Keep a simple log: lameness on a 0–5 scale, how the horse walks out of the stall in the morning, and any change in feed or work. That log is worth more to your vet than any impression.

Sourcing and quality. Ask any brand for a current certificate of analysis from an independent lab, matched to your batch, showing cannabinoid content and screening for pesticides, heavy metals and solvents. Ours are published here. Avoid products that don't state milligrams per serving.

Cautions and side effects.

• Tell your vet, especially if your horse is on bute, Equioxx or other medication. In one equine study, liver enzymes rose in 8 of 12 horses on CBD and returned to normal within 10 days, and mild low calcium was seen in all of them (Yocom et al. 2022).
• Metabolic horses: a study in Connemara ponies flagged an increased insulin response, so take extra care with horses prone to equine metabolic syndrome or laminitis. More in our pony insulin study write-up.
• Competition horses: cannabinoids are prohibited under FEI, USEF and HISA rules, and there is no published withdrawal time. Use hemp for pleasure, rehab, retired and rescue horses only. More in our horse safety guide.

When to Call the Vet

• Any new lameness that hasn't settled in a couple of days, or that keeps coming back after rest.
• A new firm swelling around the pastern or just above the coronary band.
• Sudden, severe lameness, heat or swelling in the pastern, especially after a fall or kick, which could mean a fracture or joint infection.
• A horse already diagnosed with ringbone that is getting worse despite its current plan.
• Any lameness in a horse with a history of laminitis or metabolic disease.
• Before buying a horse with pastern lumps or a known ringbone history.

What to Do If You Suspect Ringbone

1. Write down and film what you see. Which leg, on what ground, on which rein, and since when. Short phone videos at the walk and trot help your vet.
2. Book a lameness exam, not just X-rays. Blocks first, then films, so you know the ringbone is actually the source of the pain.
3. Ask the two key questions. High or low? Articular or periarticular? Those two answers shape the whole plan.
4. Get your farrier and vet talking. Bring the X-rays to your farrier and ask how they plan to balance the foot and ease breakover.
5. Agree a step-by-step plan. NSAIDs and rest, then joint injections, then a discussion of fusion if the horse is still lame. Ask your vet for realistic success rates for your horse's leg and type of ringbone.
6. Manage the basics. Good footing, a sensible body weight, regular trims and consistent, moderate exercise.
7. Add supportive care with your vet's OK. A daily supplement routine can sit alongside the main plan, never in place of it.

Frequently Asked Questions

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The Short Version

Ringbone is arthritis of the pastern joint (high) or coffin joint (low). It cannot be reversed, but most horses can be kept comfortable with rest, anti-inflammatories, good farrier work and joint injections. When high ringbone keeps hurting, pastern fusion gives about two in three horses their working life back, with hind legs doing better than front. Low ringbone is harder, and often means a gentler job. Hemp can be part of the daily routine alongside that plan, but no study has tested it in ringbone.

Bute for Horses · Equioxx for Horses · Adequan for Horses · Banamine for Horses · Navicular Disease · Laminitis · Kissing Spine · CBD for Senior Horses

These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. This article is general information, not veterinary advice. Consult your veterinarian before use, especially if your horse is pregnant, nursing, competing, or taking medication.