The first three-legged dog I knew was named, appropriately, Troika. She had been a stray who was struck by a vehicle. She suffered a catastrophic injury to her left front leg in the incident. She was rescued by a veterinary student, and the limb was amputated. That veterinary student was a classmate of mine at UC Davis in the 1990s. In that era, the veterinary school hosted weekly events called “TGs.” Every Friday, the students and many of the faculty would gather with a keg of beer, a barbecue, potato chips, salad, and dogs. Lots of dogs. In fact, those TGs could have had a subtitle: Dogs Gone Wild. My kindhearted classmate was not alone among veterinary students as a dog lover. Half of the people who came to those TGs brought dogs, and those dogs really knew how to party. A large pack formed every Friday to engage in fetching, chasing, begging, peeing, pooping, and humping. Here is what I remember about Troika: She always led the charge (in the fetching and chasing, at least).

Since the 1990s I have known many, many three-legged dogs, and they generally have had that in common. They generally manage to outrun everybody else at the dog park. They generally are the first to the ball after it leaves the Chuckit. I don’t know whether it’s coincidence or whether tripod dogs are out to prove something. But I do know this: Dogs can lead absolutely normal lives with a missing limb. It does not matter whether the missing limb is in the front or the back. Whether a dog is born without a leg or loses a leg to injury or cancer, one thing is nearly certain: The dog won’t act like he misses it.

This raises a question: How low can a dog go? Just how many legs does a dog need to lead a happy life? The answer is zero. Let’s work our way down. I will assume that every dog lover has known three-legged dogs, so for most folks the fact that dogs can be happy without a limb is essentially self-evident. But what about two-legged dogs? Dogs with two legs need to adapt. And they almost always do. It is most common for dogs to lose or be born without either both front legs or both hind legs. And in either case (for small dogs especially) it turns out that dogs can walk on two limbs. Dogs missing front limbs tend to do especially well. It is relatively easy for a dog to shift his center of gravity to a spot over the hind limbs by leaning backward. A cursory Google search will reveal many images of such dogs strolling down the street, or hopping along like kangaroos. Dogs who don’t have rear limbs also can do just fine. Small dogs especially are able to shift their weight to the front limbs in order to walk. See the video below of the two-legged Boxer named Duncan Lou Who:

This is a more challenging task for larger dogs, or for dogs such as Dachshunds or Corgis with especially long backs. Fortunately, such dogs usually don’t have to go through life alone. If such a dog has a human companion, then a world of resources opens up. Dog wheelchairs or carts have been around for decades, but in recent years there has been astronomical progress in the development of mobility devices for disabled canines. So even if a dog can’t walk on two legs, he can still happily and readily get around with a cart. It is less common, but not unheard of, for dogs to lose one limb in front and one in back. If the missing limbs are on opposite sides, the dog often can make a go of walking. Things are more difficult if the missing limbs are on the same side; such a situation makes balancing tough. However, never underestimate the spirit of a dog — it absolutely is possible for such dogs to walk and run.

And even if they can’t they’ll get along just fine with a cart. It is hard to imagine a one-legged dog walking (although I wouldn’t put it in the realm of the impossible for such a creature to find a way to hop around). However, one leg is all that’s needed for a dog to propel himself in a cart. Dogs with no legs are rare. Such circumstances usually arise from birth anomalies. Traumatic injury, or — sad to say — abuse at the hands of a sociopath also could lead to a dog with no legs. Small dogs with no legs can be carried by their owners. And never underestimate a dog’s resourcefulness — I have seen videos of dogs without legs moving around on bedding without appearing distressed in the slightest. Also, be aware that the field of canine prosthetics is exploding. Veterinary journals regularly publish case studies in which resourceful humans craft artificial limbs for disabled dogs. If even a small portion of a single limb remains, a prosthetic device can probably be designed to allow the dog to propel himself in a cart. Regardless of how many limbs a dog has, he can be counted upon not to dwell on his circumstances. Dogs love life, and they power through adversity. We can learn a great deal from them.

Learn more about dogs with Dogster:

• The 10 Biggest Misconceptions About Guide Dogs for the Blind
• 6 Things to Remember When You Have a Fearful Dog
• Four Things You Should Know About Your Dog’s Growl

Got a question for Dr. Barchas? Ask our vet in the comments below and you might be featured in an upcoming column. (Note that if you have an emergency situation, please see your own vet immediately!)