Why Do Dogs Have an Extra Finger on the Feet?

Agility and working dogs need dewclaws to help with traction.
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Dogs have four digits on each foot, but it's typical for them to also have a fifth finger on their front feet and sometimes on their hind feet, too. They're called dewclaws, and your pooch may have them but you'll have to look closely, as they're located up the wrist a short way from the rest of his fingers. Dewclaws are sometimes considered useless, but there are times when those extra fingers come in handy.

What Are They Good For?

Just a cursory glance at Rudy's dewclaws and you might think they're useless little digits. But dewclaws have several tendons attached to them that assist your dog in moving. If Rudy is running, for example, his front feet hit the ground in a way that his dewclaws actually do make contact with the ground, digging in to support his legs and prevent torque. This means that if Rudy is a working dog or a competitor in agility, he'll need his dewclaws to help keep from stretching and tearing his carpal ligaments. Extremely active dogs without their dewclaws can develop arthritis in their wrists from the stress that the extra finger would have relieved.

To Remove or Not to Remove

If your dog is a dog of leisure and isn't into agility, he won't have much use for his dewclaws. In fact, they can become a nuisance, getting caught on things like carpeting in the house or brush and other items outdoors. It can be painful if this happens to Rudy, especially if his dewclaws tear. That could even lead to infection. This is the reason that most people choose to have the extra fingers removed from puppies, usually when they're around 3 to 5 days old. However, there are reasons to leave a pup's dewclaws intact other than on working and agility dogs who need their dewclaws for running and jumping. Some breed standards, like the Great Pyrenees, stipulate that show dogs have dewclaws not only on their front feet, but on their rear feet, as well.

Veterinary Care Required

You should always have your vet remove the dewclaws from puppies rather than attempting to do it yourself. If it is done incorrectly it could result in deforming or crippling the pups. The vet will be able to perform the procedure without harming them. If you want the dewclaws removed from an older puppy or dog, it's a major operation that would require anesthesia, making the vet the only safe and logical option.

Nail Trimming

If Rudy's dewclaws are intact, the nails on them will grow just like the rest of his nails. They may even seem to grow longer quicker, as they don't get worn down through everyday walking. Make sure that the nails are trimmed to a short length without cutting into the quick. If the nail on a dewclaw grows too long, it could curve back around and grow into the pad of the dewclaw, which would be very painful and could cause infection. Have a professional groomer or vet clip your dog's nails and show you how.