I have a three-year-old Thoroughbred filly who was shipped from Texas. When she arrived, she had a swelling on her hock that was called a capped hock. What exactly is a capped hock and how should I deal with it? Will it affect her ability to race successfully?

PHOTO BY DUSTY PERIN

To understand fully what a capped hock is, it is helpful to know something about anatomy. The horse’s body, like a human’s body, is filled with sacs knows as bursae. These sacs are filled with synovial fluid and are found at points where there are bony protrusions like the hock, or the human elbow. There also is one that lies deeper within the shoulder. These bursae are located at these points to help facilitate the movement of the tendon over that particular angulation. They are, in short, cushioning devices.

A capped hock is merely a distention and inflammation of the bursa that lies at the point of the hock. This is a common injury in all horses, not just Thoroughbreds. It is not anything that develops on its own, but rather is caused by some kind of injury to that particular area