Capped Elbow Treatment in Horses by a Vet – 2025 Guide to Shoe Boils, Prevention & Recovery 🐎💉

By Dr Duncan Houston, BVSc

Introduction

If you've noticed a soft, fluid-filled swelling at your horse’s elbow—particularly on the backside of the joint—you may be dealing with a capped elbow, also known as a shoe boil. In 2025, this condition remains a challenge to treat effectively, but early recognition and prevention can make a significant difference.

What Is a Capped Elbow? 🤔

• A fluid-filled swelling that develops at the back of the elbow joint
• Caused by repetitive trauma, typically from the horse's own hoof or shoe hitting the elbow when lying down
• Similar to a hygroma in dogs or capped hocks in horses

Causes of Shoe Boils 🔍

• Most commonly from the horse's heel striking the elbow while rising or lying down
• Can occur in both shod and barefoot horses
• More frequent on hard ground or bedding lacking cushioning
• Occasionally from external trauma or repeated pressure from laying down

Symptoms 📋

• Soft, movable swelling near the point of the elbow
• Usually not painful unless infected
• May fluctuate in size depending on activity level
• Occasionally becomes firm or fibrous if chronic

Diagnosis 🩺

A veterinarian can confirm the diagnosis by:

• Visual inspection and palpation
• Ultrasound to assess bursa thickness and fluid content
• Ruling out joint involvement or abscess

Why Treatment Is Challenging ⚠️

• The bursa that forms continues to secrete fluid
• Even if drained, it typically refills unless the pressure source is removed
• Infection risk is high with invasive drainage or surgery
• Recurrent trauma from lying down can reopen surgical sites

Treatment Options 💉🧼

1. Drainage

• Sterile aspiration can reduce swelling temporarily
• Must be done with strict aseptic technique
• Risk of introducing infection is high

2. Compression & Anti-Inflammatories

• Use of pressure bandages post-drainage
• Topical or systemic NSAIDs to reduce inflammation

3. Surgical Treatment

• Excision of the bursa may be performed for chronic or fibrous cases
• Difficult to manage due to constant pressure when horse lies down
• Horse must be tied or cross-tied for 3 weeks post-op to prevent dehiscence

4. Cauterization

• Applying strong iodine to scar and shrink the bursa lining
• Less commonly used due to irritation risks

Prevention Is Key 🧲

Shoe Boil Rolls

• Doughnut-shaped pastern wraps
• Prevent the heel from striking the elbow during lying down
• Recommended for any horse prone to capped elbows

Additional Prevention Tips

• Provide soft bedding or stall mats
• Avoid prolonged time on hard ground
• Monitor horses with history of shoe boils during travel or show stabling

Case Example: Performance Horse with Chronic Shoe Boil

1. 7-year-old gelding presented with soft elbow swelling, recurring despite draining
2. Surgical removal attempted, but wound reopened within 5 days
3. Rehab plan included tie-stall rest for 3 weeks, topical antibiotics, and NSAIDs
4. Shoe boil roll applied once healed to prevent recurrence

FAQs About Capped Elbows 🧠

Q: Is a shoe boil dangerous?

A: Not usually—but if it becomes infected or fibrous, it can cause discomfort or permanent swelling.

Q: Can it resolve on its own?

A: Small swellings may regress with padding and a shoe boil roll, but chronic ones often persist.

Q: Does it require antibiotics?

A: Only if there's infection. Most are sterile unless punctured or drained improperly.

Conclusion

Capped elbows are tricky—not because they’re medically dangerous in most cases, but because they are frustratingly recurrent and resistant to treatment. Prevention is your best ally. Use soft bedding, manage early signs quickly, and apply a shoe boil roll if needed. If the swelling becomes large or chronic, consult your veterinarian for safe drainage or surgical options.

Need help managing a persistent capped elbow? Visit AskAVet.com or download our app 📱 to connect with Dr Duncan Houston for customized treatment plans and prevention strategies. 🩺🐴