Horses have been around for a long time. And they have been hurting themselves for a long time (shocking, I know). So there are some interesting terms that have developed over the years to describe these various ailments. Here are just a few and their definitions:
Bone Spavin: arthritis of the hock joint
Curb: distention or inflammation on the plantar tarsal ligament. This ligament is on the outside and back of the leg, just below the hock. It can become inflamed from over-flexing the hock.
Shoe boil: a swelling that occurs at the point of the elbow, usually caused by inflammation from pressure of the hoof onto the elbow when the horse is laying down
Thoroughpin: a swelling that occurs above the hock on the outside of the leg. This swelling indicates inflammation of the tarsal sheath of the deep digital flexor. This usually does not cause any lameness.
Capped hock:This is a soft swelling at the point of the hock (the calcaneus), usually caused by trauma such as kicking walls, etc. This usually does not cause lameness.