Horse anatomy
Stifle
A joint in the hind leg, like a knee. Bends as the horse steps and pushes off.
A closer look
The stifle is the joint high on the hind leg, at the front of the thigh near the flank, and it matches the human knee. Like our knee, it has a kneecap, called the patella. The stifle and the hock below it are linked, so they bend and straighten together.
Why it matters
The stifle is one of the largest joints in the horse's body. It helps drive the horse forward and takes a lot of force when the horse lands, stops, or turns, so stifle problems can affect the whole hind leg.
Care tip
Find the stifle by running your hand down from the flank to the bony bump at the front of the thigh. Swelling, heat, or a stiff, catching step in a hind leg are worth reporting to an adult.
Common mistake
Many people think the joint that points backward on the hind leg is the horse's knee. That joint is the hock; the true match for the human knee is the stifle, higher up near the belly.
Fun fact
Horses can lock their kneecap in place, which helps them doze standing up with almost no muscle effort.