Bone spavin in horses: causes, symptoms and treatment

What exactly is bone spavin?

Bone spavin is osteoarthritis of the small joints on the inside of the hock, particularly the distal intertarsal joint and the tarsometatarsal joint. Wear or overloading damages the cartilage, and the body responds by forming bone tissue to stabilise the joint. In the early stages this bone formation is painful; once the joints are fully fused (ankylosis), the pain often disappears on its own. That process takes an average of one to three years. Young horses aged 5 to 10 are disproportionately affected, but older horses can also develop spavin. Warmbloods and horses that do a lot of jumping are at higher risk.

Recognise the early signs

Spavin often begins subtly. Watch for these signs, especially after rest or in cold weather:

• Stiffness in the first steps after getting up or after standing still
• Mild lameness in one or both hind legs that 'works out' after 10–15 minutes
• Visible swelling on the inside of the hock joint
• Reduced flexion of the hock joint during movement
• Positive flexion test of the hind leg during veterinary examination

Diagnosis: how do you confirm spavin?

Do you suspect spavin? Consult your veterinarian. The diagnosis begins with a clinical gait assessment and a flexion test. This is almost always followed by X-ray examination: radiographs can reveal bone growths, narrowing of the joint space and sclerosis. An ultrasound can provide additional information about soft tissues. Sometimes a diagnostic nerve block is injected to confirm the source of pain. Record the findings, X-rays and veterinary reports in one place immediately in the EquiSight horse profile, so that you have a complete overview ready at follow-up consultations.

Treatment options at a glance

There is no treatment that reverses osteoarthritis, but the symptoms can be managed effectively. The approach depends on the stage and severity:

• NSAIDs (such as phenylbutazone) for pain relief in acute and painful phases
• Intra-articular corticosteroids or hyaluronic acid for local anti-inflammatory effects and joint lubrication
• Radiofrequency ablation (RFA) or chemical ankylosis with sodium monoiodoacetate to accelerate fusion
• Surgical ankylosis in persistent cases where conservative treatment is insufficient
• Bar shoe or orthopaedic shoeing to reduce the load on the hock joint
• Targeted physiotherapy or rehabilitation training to support the surrounding muscles

Movement and training with spavin

Rest is rarely the best solution. Controlled movement keeps the joint environment supple and slows further degeneration. A progressive schedule of 20 minutes of walking per day is a good starting point during a painful phase. Once the horse moves more comfortably, you can gradually build up with more walking and light trotting. Avoid heavy collection, sharp turns and a lot of jumping as long as the joint is irritated. Use the calendar in EquiSight to track training sessions and recovery periods, and ask EquiCoach for a training schedule tailored to the stage of recovery.

Nutrition and supplements: what works?

No supplements can cure osteoarthritis, but several ingredients can support joint health. Always consult your veterinarian about dosage and combinations:

• Glucosamine and chondroitin sulphate: support cartilage metabolism, beneficial with long-term use
• MSM (methylsulfonylmethane): has anti-inflammatory properties and is well tolerated
• Omega-3 fatty acids (linseed, fish oil): reduce systemic inflammation
• Turmeric (curcumin): promising, but bioavailability in horses is limited

Prevention and long-term management

You cannot always prevent spavin, but you can reduce the risk and slow its progression. Ensure correct hoof balance: an imbalance of just a few millimetres noticeably increases pressure on the small tarsal joints. Have hooves trimmed every 6 to 8 weeks by a qualified farrier. Build training intensity gradually, especially with young horses. Keep an eye on weight: every extra kilogram increases the load on the joints. Regularly record hoof scores, weight and movement patterns in the EquiSight horse profile so that you can spot trends early.