By: Dr. Lydia Gray

What is it?

This X-ray shows a horse’s foot, with Sidebones present on both sides of the coffin bone

Sidebone is hardening of the cartilages on either side of the coffin bone in the hoof. Experts aren't sure why these usually springy tissues calcify, or turn to bone, but theories include genetics, hoof concussion or trauma, poor hoof and limb conformation, and poor trimming and shoeing. Sidebone is primarily seen in heavier breeds such as draft horses, warmbloods and cob-type ponies.

What can be done about it?

Because Sidebone itself is not believed to be a significant cause of lameness but an accidental finding on X-ray of the foot, no specific treatment is necessary. However, fracture of these cartilages or damage to nearby ligaments may be an issue when lameness is localized to the foot. Ultrasound, nuclear scintigraphy or advanced techniques such as MRI or CT may help determine how active the Sidebone is in a horse and if any inflammation is present.

What else do I need to know?

The cartilage tissue involved in Sidebone is specifically known as the collateral cartilages. Quittor is the name of condition when the cartilages in the hoof actually become infected. This can be a significant cause of lameness and should be promptly diagnosed and treated to prevent further tissue damage.


SmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.