Managing Navicular Syndrome
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- 8 min read
Navicular syndrome is a chronic degenerative condition affecting the structures within a horse’s hoof, especially the navicular bone and surrounding tissues. It’s a leading cause of front limb lameness in mature riding horses. Most veterinarians regard it as ‘incurable’.
A diagnosis of navicular syndrome is very distressing for any horse owner, but there is hope.
There are aspects of management that you as a horse owner can control.
What is a syndrome?
A syndrome is a collection of signs and symptoms that tend to occur together and characterise a particular condition or disorder. It doesn’t always point to a single cause—it’s more about the pattern of clinical features. Unlike a disease, which usually has a defined cause, a syndrome might be multifactorial or idiopathic (which is a medical word for “we don’t know”).
Navicular syndrome involves damage to the navicular bone, navicular bursa, deep digital flexor tendon (DDFT), and/or other soft tissues in the heel region of the hoof. Being a ‘syndrome’ it’s not a single disease but a collection of related pathologies that result in chronic heel pain and lameness, often in both front feet.
Key Signs and Symptoms of Navicular Syndrome
Intermittent or chronic lameness, especially in the front limbs
Shortened stride, particularly on hard surfaces
Reluctance to turn or work in circles
Choppy gait and toe-first landing
Improved movement after rest, but worsens with work
Causes and Risk Factors
Poor hoof conformation (negative palmar angle and broken back hoof-pastern axis)
Biomechanical stress from repetitive concussion
Genetic predisposition
Vascular compromise within the navicular bone
Shod horses are more likely to suffer navicular syndrome than barefoot horses
Stabled horses are more likely to suffer navicular syndrome than turned out horses.
Navicular syndrome is rare in ponies and the feral population (which generally don't exceed 15hh) so there may be an element of scale.
It is most prevalent in showjumpers, reiners and similar sport horses. There is clearly an element of wear and tear. But it is not necessarily just concussion, because while navicular syndrome can occur in gallopers, subject to high-velocity strain, sustained speed and stride extension, they are more likely to succumb to suspensory ligament strain or fetlock issues.
It seems to occur more in horses that routinely perform abrupt stops, sharp turns, sliding, roll-backs and hyperextension of tendons and ligaments during take-offs and landings over obstacles.
Feral horses do many more miles every day than domestic horses, but they don't generally voluntarily jump obstacles and spin. While a horse's physiology allows it, it's not natural to perform these movements repetitively and routinely.
Diagnosis of Navicular Syndrome
Veterinarians use a combination of:
Clinical examination
Hoof testers
Nerve blocks
Radiographs or MRI to assess bone and soft tissue changes (general anesthesia is required to conduct an MRI)
Routine Treatment and Management
Veterinary treatment for navicular syndrome focuses on managing pain, improving hoof mechanics, and slowing disease progression. While vets claim it’s not curable, many horses can return to work temporarily using these methods.
Veterinarians manage navicular syndrome with:
Corrective shoeing to support the heel and reduce stress on the navicular region - rockers, wedges, egg bar or heart bar shoes (short-term relief, but rarely long-term soundness)
Anti-inflammatory medications (which in the long-term can cause ulcers and leaky gut)
Bisphosphonates to slow bone degeneration (another medication with potential side effects, such as gastrointestinal upset, not recommended to be used alongside NSAIDs due to potential kidney damage)
Corticosteroid injections: Target inflammation in the navicular bursa or coffin joint. 30% of horses improve with steroid use. Long-term steroid use causes a whole range of nasty side effects. One of which is osteoporosis. Given that bone density loss is already likely to occur with navicular syndrome, this seems to be a suboptimal solution. Other side effects are cataracts and glaucoma (blindness), muscle wastage, immune suppression, adrenal suppression and sometimes death. Death is a particularly bad side effect. You should probably try to avoid that one.
Shockwave therapy (~$3000 for a course + travel expenses), it is unclear how useful this therapy is.
Turnout. I like this one. It's the only one that is natural, and is about promoting healing rather than masking symptoms. There’s no blindness or kidney failure or death associated with spelling. It is less popular though, because results are measurable in months not hours, and you can't put it on the invoice.
Just a side note here: Old farrier books, and we’re talking less than a century ago, recommend pulling shoes and spelling for all kinds of conditions that relate to repetitive strain, concussion or wear.
“Hickman’s Farriery” from 1977, for example, was a foundational text for farriers and veterinary students. It references spelling as a vital part of hoof rehabilitation, particularly for horses with navicular symptoms, laminitis, or chronic bruising.
Question - if you don’t know what’s causing it, how do you know it’s not curable?
If it starts with heel pain, what are the most widespread and obvious causes of heel pain?
Repetitive strain on tendon and ligaments as per above.
Abscess. But that’s not usually bilateral (in both feet at once).
Bruising, but that’s generally temporary, not chronic.
Potentially laminitis, but usually that’s pain in the front of the hoof with heat in the hooves and bounding pulses, which are not common symptoms of navicular syndrome.
Thrush. While no studies formally document co-occurrence of navicular syndrome and thrush, several sources emphasise that poor hoof care, long toe–low heel conformation, and contracted heels, common in navicular cases, also predispose horses to thrush.
The problems associated with navicular syndrome are all downstream of the initial heel pain.
This article emphasises how the toe-first landing is the cause of the problem and not the other way around.
If there is pain in the heel, horses begin to toe-land and adopt a posture that reduces pressure on the heel - like standing over at the knee. Over time these postures and movements remodel the bones, and that in turn causes strain on the tendons, which causes more heel pain. This bone remodelling, inflammation and tendon damage is what vets are looking for to reach a diagnosis of navicular syndrome (all downstream of the original source of the pain).
Bone Density Loss
The theory is that distal (furthest away from the centre) bone density loss in “navicular syndrome” can occur due to reduced mechanical loading, vascular compromise, and chronic inflammation affecting the navicular bone and surrounding structures.
1. Reduced Mechanical Loading
Horses with navicular pain often shift weight away from the heel, landing toe-first.
This altered gait reduces normal mechanical stimulation of the navicular bone.
Bone requires regular loading to maintain density—without it, osteoclastic activity increases. Basically osteoclasts break down bone and reabsorb the minerals.
2. Chronic Inflammation and Synovial Penetration
Inflammation in the navicular bursa and adjacent structures can trigger synovial fluid invasion into the bone. Synovial fluid is the gel-like lubricant between joints.
This process erodes the medullary architecture (this is the spongy part of bone), especially at the distal end.
Combined with fibrocartilage damage on the flexor surface, this leads to progressive degeneration.
3. Medullary Sclerosis and Remodeling Imbalance
As bone density decreases, the body attempts to stabilise the area by laying down sclerotic bone. This new bone is often poorly organised and less functional, contributing to stiffness and pain.
In short, first there is heel pain, and then there is toe walking, gait changes and posture changes, and then we have bone density loss, chaotic bone remodelling and compromised vasculature.
All of the research focuses on biomechanics, genetics and conformation factors. What if the bone density loss is because the diet is deficient in the ingredients that make bones (calcium, phosphorous and magnesium)? Horses on high oxalate pastures - kikuyu and setaria in particular - are frequently deficient in calcium. Potentially horses are robbing their own bones for those minerals - starting distally (at the ends), and this contributes to the pain that causes the toe-first landing, and that becomes a cycle.
Blood Flow & Vascular Compromise
The distal border of the navicular bone is supplied by small arterioles.
Studies show thrombosis or narrowing of these vessels in affected horses.
Reduced blood flow leads to hypoxia, impairing bone remodeling and promoting medullary bone loss. The spongy part of the bone is responsible for shock absorption, blood cell production, and bone remodeling. In the navicular bone, this area helps distribute forces from the deep digital flexor tendon.
The hoof acts like a hydraulic pump: each step compresses and releases blood through a network of vessels. Key structures include the digital cushion, laminar bed, and circumflex artery, which rely on hoof flexion to maintain circulation.
This video is old (it starts out looking like an English detective show from the 1980s), but it shows a model of a hoof in motion with the expansion and contraction of a heel in flight and the internal structures, including flexor tendons. It shows clearly how heel compression is essential for blood flow to the hoof.
Metal shoes limit the hoof’s ability to expand and contract with each step, reducing that vasculature over time, and this is one reason why shod horses are more likely to get navicular in the first place, and why corrective shoeing rarely improves navicular syndrome in anything other than the very short-term.
Furthermore - this expansion and contraction of the hoof in motion causes the hoof to expel the dirt plug, which is nature’s way of keeping the hoof clean. Shod hooves can’t expel their dirt plug, or at least it’s less frequent. You need to do that manually. Many owners don’t pick their hooves every day, which makes thrush more likely.
Key Takeaways
Don’t give up hope.
Here are ways you can manage your horse that you can completely control:
If the cause is repetitive strain from jumping, reining, or similar, the horse is probably no longer suitable for this discipline. That doesn't mean it's not suitable for less demanding activities. If that means it’s not the right horse for you any more, that doesn’t mean it’s not the perfect horse for someone else.
If you have ruled out repetitive strain, the most widespread and obvious cause of heel pain is thrush. Given that topical treatments are cheap, thoroughly cleaning your horses hooves daily is free - and neither have any negative side effects, it’s definitely worth ruling out whether fungal and bacterial infections in the hoof are contributing to lameness.
Whether bone density loss comes before or after, feeding for optimal bone health gives your horse the ingredients to maintain healthy bones. These are macro-minerals calcium, phosphorus and magnesium - ideally fed in the correct ratios. You can read this article about feeding for bone health.
If chronic inflammation of the structures inside the hoof contribute to navicular syndrome, natural anti-inflammatories are a better option for long-term use than medications as they don’t have the side effects of ulcers or leaky gut, kidney damage (or death).
Barefoot hooves expand and contract naturally which improves blood flow, loads the bones which helps maintain density, and naturally expels the dirt plug. This has the potential to vastly improve hoof function.
Given that navicular is considered incurable, and that veterinary methods of treatment are more about masking the symptoms of pain, and slowing progression of the degeneration - not reversing it - and that in general, navicular health improves with rest - an extended spell with adequate turnout is a legitimate option.
These are all about naturally returning function to the hoof, rather than slowing the progression of degeneration - and they are far cheaper.