Answer Man

Broken leg? Be glad you’re not a horse

Q: During the races leading up to the final event of the Preakness, two horses died. One had a heart attack, the other broke a leg and had to be “put down.” Why? If a dog breaks its leg, we take it to a vet and immobilize the leg with a splint or a cast, just as humans are treated for the same injury. Why can’t this be done for horses?

Bill Craft, of Edwardsville

A: Is there a sadder moment in a stereotypical Western than when the rootin’-tootin’ cowboy hero has to shoot poor Old Paint after it fractures one of its once-sleek, powerful limbs? Why, it can bring a tear to the eye faster than you can say “ol’ Yeller.”

Of course, such a fate was understandable in the wild, wild West of the 1800s. While chasing the guys in the black hats, you couldn’t very well email your vet to come treat your trusty steed in the middle of an Oklahoma mesa. But with all the advances we’ve made in medicine, surely this grim picture has changed after 150 years, right?

Sorry, pardner, not much. Despite the most revolutionary animal rehabilitative services available, even a Triple Crown winner likely would have to be euthanized immediately should it stumble and break a leg while enjoying life on the stud farm. Once you learn a little about the physiological and behavioral differences between horses and humans (and dogs, cats, etc.), it’s not hard to understand why.

All you have to do is look at a horse and human side by side to get a major clue. If you break a leg, usually the worst you can expect is having your broken bone(s) set and your leg put in a cast for several weeks or months as it heals. Often you’ll be moving around in a walking cast before it fully heals. Despite the inconvenience, recovery is in most cases relatively quick and painless.

“Our bodies are relatively light compared to a horse’s and our leg bones are larger in ratio to a horse’s,” says horse expert Katherine Blocksdorf, writing on about.com. “We also know that we must stay off of the injured leg, so that the bones mend properly without stressing or damaging the healing bone.”

In contrast, the average horse can weigh in excess of 1,200 pounds. That’s a half-ton more than most humans — and it often has to be supported on lighter leg bones developed through selective human breeding. That’s especially true, for example, on those thoroughbreds that so often make the headlines when they are “put down.”

“When (horses’) bones break, it often means they shatter,” Blocksdorf said. “And it’s almost impossible to reconstruct the fractured leg. While (humans) have some large muscles and a bit of tissue below the knee that helps stabilize a broken bone along with your cast, a horse has no muscle or any other tissue besides tendons and ligaments below the knee. Even with a cast, the broken bone has little to support it.”

Eighty of a horse’s 205 bones — nearly 40 percent — are in the horse’s legs (humans have 62, albeit in two legs not four). When you consider the pounding that those legs take while supporting hundreds of pounds being urged on to fly to a two-minute Kentucky Derby finish, it’s probably surprising that they’re aren’t even more injuries. According to a New York Times study, about 1,200 thoroughbreds die in races each year, roughly one out of every 200 times a horse leaves the gate.

“And there are many fragile bones below the knee and hock,” Blocksdorf said. “Some of the bones are within the hoof, and when they shatter, they are far more difficult to stabilize and let heal. Even if a horse’s bones are healing, other complications can set in, such as static laminitis ( a disease of the foot of hoofed animals), making it difficult for the horse to fully recover without living a life of unsoundness and pain.”

To this rather fragile physical makeup you have to add one more downside: a horse’s instinctive behavior that has evolved over the millennia. When we break a leg, we simply stretch out on a sofa or bed whenever the discomfort becomes too great. If my cat broke a limb, it probably would curl up in my bed and sleep 23 hours instead of 22.

Horses, on the other hand, literally don’t know what it means to get off their feet. They are biologically programmed to stand much of the time — even while they sleep. As a species of prey, they still are always ready to gallop from a dangerous situation. Unless you used some sort of fancy sling that could both immobilize them while keeping them upright, making a horse wait patiently for a month, two months or longer would be impossible. Even then, the sling might produce the same kind of life-threatening pressure sores, humans sometimes develop in hospitals and nursing homes. A horse’s weight, infection and pain as well as cost all play a role.

“They are creatures of flight,” Blocksdorf said. “That means a horse is likely to instinctively flee when it’s startled instead of reasoning that it must keep weight off of its fractured leg. The chances of re-injury are high.”

That said, not all leg injuries today result in a death sentence. If a bone merely cracks without fully breaking (a so-called “greenstick” or stress fracture), a horse often can recover successfully. Younger horses also stand a better chance of surviving because they are lighter and their bones are still growing. The location of the break also plays a role: A fracture in the lower leg, for example, poses a graver threat because there are fewer blood vessels to aid healing. To prevent fractures, responsible owners mix exercise along with plenty of rest and a host of nutritional supplements.

Even with all the time and money in the world, owners usually can’t allow their injured equines to ride peacefully into the sunset. Remember the sad case of Barbaro, who won the 2006 Kentucky Derby by 6 1/2 lengths before breaking his right hind leg in more than 20 places in the Preakness? After struggling for months to recover, he was euthanized on Jan. 29, 2007, when his owners said they wanted to end his suffering.

Today’s trivia

What famous piece of classical music celebrates the battle of Borodino?

Roger Schlueter: 618-239-2465, @RogerAnswer

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