I went down the rabbit hole years ago of why horses don't recover from alot of leg injuries. It's pretty interesting if you never learned exactly why. I always just accepted that if they break their leg, they got put down, but not the why.
A lot of people think it's just because a horse breaks its leg, but it's more complicated than that. Horses have relatively poor blood supply to the lower parts of their legs, which makes healing slower. On top of that, they weigh over 1,000 pounds and can't stay off the injured leg like humans can. They have to stand most of the time, so the healthy legs end up carrying too much weight, which can lead to serious complications like laminitis. If the fracture is severe and there's little chance of a pain-free recovery, euthanasia is often the kindest option. Some horses do recover from broken legs, though. It depends on the type and severity of the fracture.
Importantly, horses don’t have the ability to send blood back to the heart from the legs without aid from systems in the hooves. So on top of it being a nightmare for leg injuries anyways, horses require their hooves on the ground (taking steps) to be able to send blood back to the heart.
I've heard they evolved to be much smaller, and it's modern, human-bred horses which are oversized. Would it also be fair to say that's caused a lot of these problems?
I'm just a natural tease. It's pretty interesting how they use their lower legs kind of like secondary hearts. They depend on them for proper bloodflow and not being able to walk causes edema and circulatory failure among other really bad things.
On top of that, their leg bones don't break like human leg bones do. They splinter and shatter like glass, which introduces a ton of other complications.
Humans do, too. If you don't walk around, your heart had to do more work. Our leg-veins have loads of one-way valves. Turns out, that our ass muscles can force those valves to pump blood easier than shitty little hearts. It's why after sitting down for a few hours, you get the dumb...lack of brain oxygen forces you into power-saving.
Yeah, it's more complicated than they are brittle or they like other horses. Their lower legs are pretty fragile. They don't have muscles in their lower legs. Their circulatory system depends on them moving. The pressure in their lower legs that is generated by moving and running helps move blood through their bodies. Without the pressure on the lower legs, they have circulatory issues and inflammation that can kill them.
Not a vet. But I remember asking myself why they can't try some kind of prosthesis and investigated the real reasons why lower legs injuries are so critical. They also tend to have inflammation in their other legs if they favor one, which can cause damage to the hoofs and structure of uninjuried legs.
Pretty simple really, it's cause they're 1 ton animals with delicate bone structure and a powerful instinct to run.
I mean, have you seen a horse's ankles before? They're thinner than your wrist, and they hold up over 1000 pounds. So this is to say that they can break pretty easily, which is important because of the second part. Horse's are kinda stupid, and their instincts tell them to run whenever they sense danger.
So like, you have a 1400 pound horse with a broken leg and a split holding the leg in position to heal. It's laying in the grass, keeping the weight off it's broken leg, when suddenly the horse hears something in the distance, and it's head suddenly jolts to alert. It hears the sound approaching, so it stands up and tries to run away, the horse's instincts override it's thoughts, and it runs away. However, it's ankle is still broken, and now has 1400 pounds slamming down on it every time the horse gallons. So naturally, the splint breaks, because that's way too much weight, and then the ankle gives out, causing the horse to fall to the ground again.
Or you can stick them in a stall for the next month and watch them slowly die from other complications caused by being held in a stall for such a long time. Turns out horses are social animals with a lot of needs that cannot be met inside of a stall.
33
u/PookieDood Jun 19 '26
I went down the rabbit hole years ago of why horses don't recover from alot of leg injuries. It's pretty interesting if you never learned exactly why. I always just accepted that if they break their leg, they got put down, but not the why.