Osselets (Fetlock Arthritis) in Horses

Fetlock arthritis is common in racehorses and high performance horses. Horses showing symptoms of osselets require prompt veterinary examination. It is important to diagnose and address arthritis early to prevent further joint damage. This disorder commonly affects either both front or both hind limbs.

Symptoms of fetlock arthritis can vary in severity depending on the progression of disease.

It is important to note that symptoms don’t always correlate to the severity of disease. Arthritis results in new bone formation around the joint. Symptoms will vary in location, presentation, and severity depending on the characteristics and progression of bone deposition in a given case.

For example, a severely affected joint may cause mild changes in performance in one horse, whereas a mildly affected joint may result in a severe performance reduction in another horse.

The fetlock is a highly mobile joint, and is subject to repeated stress during movement. The most common cause of fetlock arthritis is strain of the fetlock joint during training in young racehorses. Traumatic injury, such as fractures or osteochondrosis of the fetlock can also lead to fetlock arthritis

Diagnosis begins with a physical examination, including a lameness exam and nerve or joint blocks. If fetlock arthritis is suspected, X-rays are required for diagnosis.

If recognized early, the arthritis may be treated with stall or small pen rest for weeks to months. For more advanced disease, other possible treatments include:

• Applying cold packs to the affected area
• Administration of anti-inflammatory drugs
• Joint injections
• Arthroscopic removal of joint tissue
• Surgical correction of the joint, including surgically fusing the joint

Osteoarthritis is a progressive disease and cannot be definitively treated. Long-term treatment and preventative measures are key to management of this disease.

Fetlock arthritis has a variable prognosis regarding athletic performance. Outcome is dependent on the progression of disease, patient’s age, and response to treatment. Athletic horses often need a reduced workload or an alternative sport as their condition progresses. Some horses develop chronic lameness that requires retirement.

Fetlock arthritis can be prevented by:

• Preventing trauma to the fetlock joint
• Addressing joint abnormalities with appropriate treatments promptly
• Trimming feet appropriately

Fetlock arthritis is common in horses, particularly in racehorses and high performance horses.

• Stall rest
• Cold compression
• Anti-inflammatory drugs
• Joint injections
• Arthroscopy
• Surgery