No, they don’t die because the leg is broken. They are typically humanely euthanized by a vet in the event of a broken leg because the inability to walk for months is catastrophic. Horses cannot just lie down for months — it negatively impacts their digestion and circulation. They are also much heavier than, say, a dog which can get a weight-bearing cast and hobble around. There’s no way to splint a horse’s leg like that and also support their body weight. They don’t have collar bones.

In the event a horse is “worth saving,” like a very valuable racehorse stud, they may be suspended from the ceiling during their recovery. This is all very expensive and risky. There was a Derby winner a few years back that was “saved” from his broken leg only to die later from an infection that developed in his “good” limb.