Navicular Bursa Injections in Horses: When They Help Heel Pain

By Dr Duncan Houston

Navicular bursal injections can be one of the more useful treatments for selected horses with chronic heel pain, but they are not a first step and they are not a shortcut around diagnosis.

The navicular bursa sits deep inside the hoof, between the navicular bone and the deep digital flexor tendon. When that bursa becomes inflamed, painful, or involved in navicular syndrome, targeted treatment can sometimes improve comfort significantly. But if the real problem is a deep digital flexor tendon tear, poor hoof balance, coffin joint pain, laminitis, a hoof abscess, or soft tissue injury elsewhere in the foot, injecting the bursa may not solve the actual problem.

The best outcomes come from working out exactly where the pain is coming from before placing a needle into one of the deepest, most delicate structures in the horse’s foot.

Quick Answer

Navicular bursal injections may help horses with palmar foot pain when the navicular bursa is inflamed or when MRI and diagnostic blocks show that the navicular region is a major pain source. They are usually performed with imaging guidance, such as radiography, ultrasound, or fluoroscopy, because the bursa is deep inside the hoof and sits next to the deep digital flexor tendon. They are not appropriate for every horse with heel pain, and they should usually be considered only after a full lameness exam, diagnostic nerve blocks, radiographs, hoof balance assessment, and often MRI. Merck Veterinary Manual notes that navicular syndrome can involve the navicular bone, bursa, deep digital flexor tendon, distal impar ligament, collateral sesamoidean ligaments, and other structures, which is why diagnosis matters before treatment. (Merck Veterinary Manual)

What Is the Navicular Bursa?

The navicular bursa is a small fluid-filled sac inside the back of the hoof.

It sits between:

• The navicular bone

• The deep digital flexor tendon

Its job is to reduce friction as the deep digital flexor tendon glides over the back of the navicular bone before inserting on the coffin bone.

When this area becomes inflamed, damaged, or compressed, the horse may develop heel pain, shortened stride, toe-first landing, stumbling, or chronic front limb lameness. The problem is that pain in this region can come from multiple structures, not just the bursa.

What Is Navicular Syndrome?

Navicular syndrome is a broad term for chronic pain arising from the back of the horse’s foot.

It may involve:

• Navicular bone

• Navicular bursa

• Deep digital flexor tendon

• Distal impar ligament

• Collateral sesamoidean ligaments

• Coffin joint region

• Frog, heel, and digital cushion structures

• Hoof capsule balance and breakover

This is why “navicular disease” can be misleading. A horse may have classic heel pain but only mild navicular bone changes on X-ray. Another horse may have obvious radiographic navicular changes, but the main pain source may actually be soft tissue. University of Illinois notes that MRI is considered the gold standard for navicular syndrome because it can evaluate both bony and soft tissue structures inside the hoof capsule, unlike radiographs, which mainly show bone. (Veterinary Medicine at Illinois)

When Are Navicular Bursal Injections Considered?

A navicular bursal injection may be considered when there is evidence that the bursa or podotrochlear region is clinically important.

This may include:

• Lameness localised to the palmar foot with diagnostic nerve blocks

• MRI evidence of navicular bursitis

• MRI evidence of adhesions or inflammation between the deep digital flexor tendon and navicular region

• Pain associated with navicular bone and bursal interface disease

• Poor response to simpler treatment such as shoeing, rest, NSAIDs, or coffin joint medication

• A case where the treating vet believes direct bursal medication is more logical than indirect treatment

A large retrospective study of 101 horses found that response to navicular bursa injection with corticosteroid and hyaluronan depended on MRI-detected disease process and duration of lameness before treatment. Horses lame for less than 6 months before treatment were more likely to return to intended use and remain sound for longer. (PubMed)

That is the real-world lesson: timing and diagnosis matter.

When Navicular Bursal Injections May Not Help

A bursal injection is less likely to be the main answer when the primary problem is:

• Hoof abscess

• Laminitis

• Thin soles

• Severe hoof imbalance

• Long toes and low heels without bursal disease

• Deep digital flexor tendon tear needing rest or surgical consideration

• Coffin joint pain

• Sole bruising

• White line disease

• Higher limb lameness being mistaken for heel pain

• Neck or shoulder-related gait change

• Poor farriery or shoeing mechanics that have not been addressed

The mistake I see owners make is thinking “heel pain equals navicular bursa.” It does not. Heel pain is a region. The bursa is only one possible structure within that region.

Signs That May Suggest Navicular Region Pain

Horses with navicular region pain may show:

• Short, choppy front stride

• Toe-first landing

• Stumbling or tripping

• Reluctance to turn tightly

• Worse lameness on hard ground

• Worse lameness on circles

• Sensitivity over the frog or heel with hoof testers

• Pointing one front foot

• Performance decline

• Lameness that seems to shift between front feet

• Improvement after a palmar digital nerve block

Merck notes that navicular syndrome is often bilateral in the front feet, although one limb may appear worse. Many horses show heel or frog sensitivity with hoof testers and improve after palmar digital nerve blocks. (Merck Veterinary Manual)

Why Diagnosis Comes Before Injection

A navicular bursal injection should not be used just because a horse has sore heels.

A proper workup usually includes:

• Full lameness examination

• Hoof tester examination

• Gait assessment on straight lines and circles

• Hard and soft surface evaluation

• Diagnostic nerve blocks

• Radiographs

• Hoof balance and farrier assessment

• MRI when radiographs do not explain the signs or soft tissue injury is suspected

The key distinction is this:

A palmar digital nerve block tells you pain is coming from the back of the foot. It does not tell you whether the bursa, bone, tendon, ligament, coffin joint, sole, or hoof capsule is the main problem.

That is why MRI has become so important in advanced navicular cases. Merck notes that MRI can delineate lesions in all structures of the podotrochlear apparatus and provides a more complete definition of each case than radiographs alone. (Merck Veterinary Manual)

Why X-Rays Are Useful but Limited

Radiographs are still important.

They can show:

• Navicular bone shape

• Medullary sclerosis

• Flexor cortex irregularity

• Distal border fragments

• Enlarged synovial fossae

• Coffin bone position

• Sole depth

• Palmar angle

• Hoof balance

But radiographs cannot properly show:

• Deep digital flexor tendon injury

• Navicular bursitis

• Bursa adhesions

• Distal impar ligament injury

• Collateral sesamoidean ligament injury

• Early soft tissue inflammation

So if the horse blocks to the foot but X-rays do not explain the lameness, MRI may be needed before choosing a treatment.

How Are Navicular Bursal Injections Performed?

The exact technique varies, but the general process is:

1. The horse is restrained and usually sedated.

2. The foot is cleaned and prepared using strict aseptic technique.

3. Local anaesthetic may be used.

4. A needle is placed into the navicular bursa using imaging guidance.

5. Correct placement is confirmed.

6. Medication is injected.

7. The horse is monitored afterwards.

Commonly used medications may include:

• Corticosteroid

• Hyaluronic acid

• Antibiotic such as amikacin in some protocols

• Biologic products in selected specialist cases

The procedure requires precision because the navicular bursa is deep and closely associated with the deep digital flexor tendon. Traditional palmar approaches can involve needle passage through the deep digital flexor tendon, which is one reason newer or alternative guided approaches have been studied. A 2016 Equine Veterinary Journal study described a lateral technique designed to avoid penetration of the deep digital flexor tendon, while still noting synovial penetration risks that must be considered. (PubMed)

Why Image Guidance Matters

Navicular bursal injections are not simple surface injections.

The bursa is small, deep, and surrounded by important structures. Accurate placement matters for both effect and safety.

Guidance may involve:

• Radiography

• Fluoroscopy

• Ultrasound

• Other specialist imaging techniques

Ultrasound-guided techniques have been proposed because they can allow real-time needle placement and may reduce trauma compared with some traditional approaches. However, image-guided technique selection should depend on the vet’s experience, equipment, hoof condition, and the individual case. (Hospital Equino)

The practical point for owners: this is not a “quick jab in the heel.” It is an advanced injection into a deep synovial structure.

How Well Do Navicular Bursal Injections Work?

They can work well in selected horses.

In one 2003 study of horses with navicular-area pain that had not responded to other treatments, 20 of 25 horses, or 80%, were sound and returned to intended activity 2 weeks after navicular bursa treatment. The mean duration of soundness was 4.6 months. (PubMed)

Another study of 101 horses found that 76 of 101 horses, or 75%, returned to intended use after navicular bursa injection, with a mean response duration of 9.66 months. However, only 35% were sound at follow-up, and outcome depended on MRI findings and how long the horse had been lame before treatment. (PubMed)

So the fair owner explanation is:

Navicular bursal injections can give meaningful relief, but the response is not guaranteed, may not be permanent, and depends heavily on the underlying MRI diagnosis.

How Long Does Relief Last?

Relief may last:

• A few weeks in some horses

• Several months in many responders

• Longer in selected well-managed cases

• Very little time if the wrong structure is being treated or hoof mechanics remain poor

The studies above reported average responses of several months, but individual horses vary widely. (PubMed)

If a horse improves briefly but relapses quickly, ask:

• Was the bursa truly the main pain source?

• Is the shoeing plan correct?

• Is there a deep digital flexor tendon lesion?

• Is there coffin joint involvement?

• Is the horse doing too much work too soon?

• Is there bilateral disease?

• Was MRI performed?

• Is the heel structure still compromised?

A short response is information, not failure. It tells you the plan needs reassessment.

How Worried Should You Be?

Low Concern

This is more likely when:

• Lameness is mild and intermittent.

• The horse is comfortable at walk.

• There is no strong digital pulse.

• The horse improves with farriery and rest.

• Radiographs show mild changes only.

• MRI does not show major bursal or tendon pathology.

Action: focus on hoof balance, workload adjustment, and monitoring before jumping into advanced injections.

Moderate Concern

This is more likely when:

• Lameness is recurring.

• The horse is worse on circles or hard ground.

• Palmar digital nerve blocks improve the lameness.

• Hoof testers cause heel or frog pain.

• Radiographs show navicular changes.

• The horse is not improving with basic farriery and management.

Action: discuss MRI and targeted treatment options with your vet. Navicular bursal injection may be considered if the diagnosis fits.

High Concern

This is more likely when:

• MRI shows navicular bursitis.

• MRI shows bursal inflammation with deep digital flexor tendon involvement.

• The horse has chronic palmar foot pain.

• Coffin joint treatment or shoeing has failed.

• The horse cannot maintain work comfortably.

• Lameness has been present for months.

Action: a more advanced treatment plan is needed. This may include navicular bursal injection, specialist farriery, rest, bursoscopy in selected cases, or other targeted treatment depending on MRI findings.

Critical

Treat this as urgent if:

• The horse is suddenly severely lame.

• There is a puncture wound in the frog or sole.

• A nail or sharp object may have entered the foot.

• There is swelling above the hoof.

• The horse has fever or depression.

• The horse is non-weight-bearing.

• A septic navicular bursa, septic coffin joint, tendon sheath infection, or deep foot infection is possible.

Action: call your vet immediately. This is not routine navicular management.

When Is This an Emergency?

Navicular bursal inflammation itself is usually not a same-hour emergency. Deep foot infections are.

Call your vet urgently if your horse has:

• Sudden severe lameness

• Non-weight-bearing lameness

• A puncture wound in the sole or frog

• A nail or sharp object in the foot

• Heat and swelling extending above the hoof

• Fever or depression

• Severe pain after a recent injection

• Persistent drainage from the foot

• Strong digital pulse with severe pain

• Sudden worsening after shoeing

Sepsis of the navicular bursa is most commonly associated with deep solar penetrating wounds or distal limb penetrating injuries, and it requires urgent treatment. (PMC)

Do not remove a nail from the foot before veterinary assessment unless instructed. The direction and depth of penetration can be critical for diagnosis and treatment planning.

Risks of Navicular Bursal Injections

Risks are uncommon when performed correctly, but they matter.

Potential risks include:

• Infection of the navicular bursa

• Post-injection flare

• Pain or soreness after injection

• Failure to improve

• Needle trauma to the deep digital flexor tendon

• Accidental medication into the wrong structure

• Worsening if a soft tissue lesion is missed and work continues too soon

A general study of equine synovial injections found septic synovitis occurred at a rate of 10.4 cases per 10,000 injections, or about 1 in 967 injections, with proper aseptic technique being central to risk reduction. (PMC)

A rare case report has also described suspected iatrogenic deep digital flexor tendinopathy after navicular bursa centesis, reminding us that repeated or poorly selected injections into this region should not be treated casually. (Frontiers)

The injection can be very useful. It is still a procedure into a deep synovial structure inside the foot.

What Should Happen After a Navicular Bursal Injection?

Your vet will provide a specific plan, but aftercare may include:

• Short rest period

• Clean, dry environment initially

• Monitoring for increased lameness

• Monitoring for heat, swelling, fever, or depression

• Gradual return to controlled work

• Farrier plan review

• Repeat assessment if lameness returns

• Avoiding hard ground, deep footing, and tight circles during early return

Do not assume pain relief means the foot is “fixed.” If the horse has deep digital flexor tendon disease, poor hoof balance, or chronic heel collapse, pain relief without load management can increase the risk of worsening injury.

Navicular Bursa Injection vs Coffin Joint Injection

Both may help selected horses, but they are not the same target.

A coffin joint injection may help when:

• Coffin joint inflammation is part of the pain

• Medication may diffuse to adjacent structures in some cases

• The horse has distal interphalangeal joint pain

• The case is less clearly bursal

A navicular bursal injection may be more logical when:

• MRI shows navicular bursitis

• Bursal disease is a major finding

• Previous coffin joint injection did not help

• The vet believes direct bursal treatment is required

University of Minnesota notes that coffin joint injections are commonly used for navicular syndrome and can relieve lameness in many cases, but some horses may benefit more from navicular bursa injection. It also notes that bursal injection is harder and requires imaging to correctly place the needle. (University of Minnesota Extension)

What Else Should Be Part of the Treatment Plan?

A navicular bursal injection should rarely be the only treatment.

A complete plan may include:

• Corrective trimming and shoeing

• Shorter breakover

• Heel and palmar support

• Frog or digital cushion support where appropriate

• Hoof-pastern axis correction

• Rest or workload modification

• NSAIDs where appropriate

• Coffin joint treatment if indicated

• Bisphosphonates when bone pathology is part of the case

• PRP, IRAP, or other biologics in selected cases

• Bursoscopy in selected severe bursal or tendon cases

• Controlled return to work

• Repeat imaging or lameness reassessment

Merck lists trimming and shoeing changes, NSAIDs, bisphosphonates, intra-articular corticosteroids or biologics, navicular bursoscopy, and palmar digital neurectomy among treatment options for navicular syndrome. (Merck Veterinary Manual)

The injection may reduce inflammation. The farrier plan changes the load. Both matter.

When Is Bursoscopy Considered?

Navicular bursoscopy is a surgical endoscopic procedure that allows direct visualisation and treatment of the navicular bursa.

It may be considered in selected cases involving:

• Adhesions between the deep digital flexor tendon and navicular structures

• Significant bursal pathology

• Deep digital flexor tendon surface damage

• Contaminated or septic navicular bursa

• Cases not responding to medical management

Merck lists navicular bursoscopy as a treatment option for navicular syndrome, and surgical literature describes it as both a diagnostic and therapeutic approach for selected palmar foot pain cases. (Merck Veterinary Manual)

This is referral-level territory, not a routine first step.

Common Mistakes Owners Make

Treating Heel Pain Without Localising It

Heel pain is not a diagnosis. It is a location. The bursa may or may not be the problem.

Relying on X-Rays Alone

Radiographs are important, but they do not show the deep digital flexor tendon, bursa, or key ligaments properly.

Skipping MRI in Chronic Cases

If the horse blocks to the foot but radiographs do not explain the pain, MRI can prevent wasted treatment.

Thinking the Injection Replaces Farriery

A bursal injection may reduce inflammation, but poor hoof balance can keep loading the same painful structures.

Repeating Injections Without Reassessing

If the effect is short-lived or diminishing, the diagnosis and mechanics need review.

Returning to Full Work Too Quickly

Pain relief does not mean the internal structures are ready for full load.

Ignoring Sudden Severe Foot Pain

Sudden severe lameness may be an abscess, laminitis, puncture wound, or deep infection, not routine navicular syndrome.

What Should You Do Right Now?

If your horse may have navicular region pain:

1. Reduce Hard Work

Avoid hard ground, tight circles, fast work, jumping, and deep footing until the horse is assessed.

2. Watch the Landing

A toe-first landing can suggest the horse is avoiding heel loading.

3. Check Digital Pulses and Hoof Heat

Strong pulses and heat can indicate acute foot pain, laminitis, abscess, or inflammation.

4. Take Hoof Photos and Videos

Useful footage includes:

• Walk from the front

• Walk from the side

• Trot from the front

• Trot from the side

• Circles both directions

• Hoof landing in slow motion if possible

• Side, sole, and heel photos of the feet

5. Book a Veterinary Lameness Exam

Ask for proper localisation with diagnostic blocks before advanced treatment decisions.

6. Discuss Radiographs and MRI

Radiographs are a good start. MRI may be needed if soft tissue injury or bursal disease is suspected.

7. Involve Your Farrier

The farrier needs to know the diagnosis, radiographic findings, and treatment plan. Shoeing should not be copied from another horse.

8. Ask Whether the Bursa Is Truly the Target

Before agreeing to navicular bursal injection, ask: “What evidence shows the bursa is part of the pain source?”

That one question can save a lot of wasted time.

Prevention and Long-Term Management

You cannot prevent every navicular case, but you can reduce risk and recurrence.

Practical steps include:

• Maintain regular farrier care

• Avoid long toes

• Improve breakover

• Support the palmar foot appropriately

• Treat crushed or underrun heels early

• Protect thin soles

• Use radiographs for chronic hoof imbalance

• Avoid repeated concussion on hard ground

• Avoid excessive tight circles on hard footing

• Investigate heel pain early

• Do not keep working through toe-first landing

• Match shoeing to diagnosis and discipline

• Reassess if lameness returns quickly after treatment

• Use MRI when the diagnosis remains unclear

The best prevention is not one shoe or one injection. It is keeping the back of the foot functional and diagnosing pain before it becomes chronic.

Myth vs Reality

Myth	Reality
Navicular bursal injections fix all navicular horses	They help selected horses when the bursa or podotrochlear region is the right target
Normal X-rays mean the bursa is fine	X-rays do not properly assess the bursa or deep digital flexor tendon
A nerve block proves the bursa is the problem	A nerve block localises the region, not the exact structure
The injection replaces shoeing	Hoof mechanics are still central to long-term comfort
Relief means the foot is healed	Pain relief does not always mean structural healing
Repeat injections are always safe	Repeated deep injections should be justified by diagnosis and response

FAQs About Navicular Bursal Injections

Are navicular bursal injections safe?

They can be safe when performed by an experienced veterinarian using strict aseptic technique and imaging guidance, but risks include infection, post-injection soreness, incorrect placement, and possible trauma to nearby structures such as the deep digital flexor tendon.

How long do navicular bursal injections last?

Response varies. Some horses improve for weeks, others for months. Studies have reported mean soundness durations of several months in responders, but outcome depends on MRI findings, lameness duration, hoof mechanics, and workload. (PubMed)

Does my horse need MRI before a navicular bursal injection?

Not always, but MRI is strongly useful in chronic, unclear, or nonresponsive cases. It helps identify whether the main issue is bone, bursa, deep digital flexor tendon, ligament, or multiple structures. (Veterinary Medicine at Illinois)

Can a coffin joint injection treat navicular pain?

Sometimes. Coffin joint injections can help selected navicular syndrome cases, and some medication may diffuse toward the navicular region. But when MRI or clinical findings point specifically to navicular bursa disease, a direct bursal injection may be more appropriate. (University of Minnesota Extension)

When should I call a vet urgently?

Call urgently for sudden severe lameness, non-weight-bearing lameness, a nail or puncture wound in the foot, fever, swelling above the hoof, strong digital pulses, or severe worsening after an injection.

The Bottom Line

Navicular bursal injections can be a valuable advanced treatment for selected horses with heel pain.

But they should be used with precision.

The bursa is only one structure in a complicated region. A horse with palmar foot pain may have navicular bone disease, deep digital flexor tendon injury, navicular bursitis, ligament injury, coffin joint pain, poor hoof balance, thin soles, laminitis, or an abscess. These problems can look similar from the outside but need different treatment plans.

The safest approach is:

• Localise the lameness.

• Image the foot properly.

• Use MRI when soft tissue disease is suspected.

• Confirm the bursa is a logical target.

• Use image-guided injection technique.

• Maintain strict asepsis.

• Combine treatment with smart farriery.

• Return to work gradually.

• Reassess if relief is short-lived.

A good navicular bursal injection is not just a treatment. It is the final step in a chain of good diagnostic reasoning.

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If your horse has chronic heel pain, suspected navicular syndrome, MRI changes, or you are unsure whether a navicular bursal injection is the right next step, ASK A VET™ can help you organise the lameness history, hoof photos, radiographs, MRI findings, and questions to discuss with your treating veterinarian and farrier.