Although the equine hoof is a marvel of resiliency, it’s not made of rubber, or titanium, or diamond. As a living structure, it has its vulnerabilities, and when faced with unusual stresses, it shows them. Stone bruises, those reddish-purple (on a white hoof) or dark gray (on a dark hoof) spots sometimes visible on the soles of your horse’s feet, especially right after the farrier’s knife has removed the surface crud, are one of the most common signs that the hoof has taken some abuse. But by the time you see the bruise, it’s just a reminder of a long-past trauma; the injury is already several months old.

Fortunately, stone bruises usually aren’t serious. When they’re fresh, they can cause minor lameness, for a few minutes or a few days. Some horses seem to be able to ignore them better than others. But if a stone bruise happens right before an important competition, it’s a crisis. If your horse shows a predilection for repeatedly bruising his soles, it’s a chronic problem that you’ll want to solve.

Stone bruises generally are the product of your horse’s environment. Traveling on hard, rocky ground can batter your horse’s soles, especially if he’s used to more manicured conditions. (Remember as a kid how you tiptoed very gently over a gravel driveway early in the summer, yelping, "Ouch, ouch, OUCH!" before your bare feet had gotten tough?) But a hard knock against a solid object (a fence rail or a tree root, for instance), can have the same effect. So can shoes that are too small, or those equipped with caulks, grabs, or trailers that alter the foot’s natural flight path, or concentrate an unusual amount of pressure on a small area. Hooves that grow up and around a shoe left on too long also can bruise, particularly if the shoe is loose and bangs on the sole with every step. The end result is rather like the aftereffects of your big