Updated November 28, 2020
Quick question: how many toes does a dog have? Some people say 16, others look at themselves and say 20. The correct answer is 18.
Why such a random number? It’s because dogs have four weight-bearing toes on each foot, and only two dewclaws. Of all the toes, it’s these dewclaws that cause dogs and their owners the most trouble.
What Is A Dewclaw?
A dewclaw is the extra toe that is found on the inside of a dog’s front leg. It’s a completely normal digit with three bones, two joints and a nail. Dewclaws correspond in position to the thumb in humans except without quite the same mobility or uses.
Dewclaws are only abnormal when they appear on the hind legs. Exceptions are breeds like the Pyrenean Mountain Dog or Briard where hind dewclaws are part of the breed standard. For the rest, my guess is that less that one percent have them at birth.
What Dewclaws Are For
Dewclaws are definitely not useless. Watch a dog gripping a bone and you’ll wonder how they do it without them.
Then there’s their use in running. To demonstrate, here’s a fun task: pick up your dog’s front leg and look at its underside. Above the main four pads, even above the dewclaw you’ll see a small, circular pad seemingly lost high up on the back of the ‘wrist’. This is the stopper pad. What on earth is it for?
To answer that question, and at the same time to show what dewclaws do, just watch this video of a dog at full flight.
At a run, the wrist of a dog flexes so much that both the dewclaw and the stopper pad come into contact with the ground. The dewclaw provides extra stability, the stopper pad is a bumper that protects the carpus.
Why Dewclaws Break or Split
Most urban dogs don’t run enough to wear down their dewclaws. Reasons include:
- A lack of suitable spaces
- A lack of owner time
- Medical reasons such as arthritis or being overweight
- Not enough bodyweight to wear the nail down
- Dogs that just don’t want to run!
It’s perfectly fine to just walk your dogs; the important thing is getting out, not what you do. However, for these dogs, the dewclaw often gets too long, like in the middle picture at the top. Then, it curls into a hook shape, which easily catches on anything.
Most of the time we don’t see what actually catches it, but the result is a nail that is either:
- Pulled out completely
- Half-removed (a ‘hang-nail’)
- Split down the middle
Either way, this is very painful.
What To Do If A Dog Breaks A Nail
A dog that pulls out a nail needs the exposed nailbed protected from trauma and infection. This requires a vet to gently clip away the hair, apply a semi-occlusive dressing and use antibiotics. It’s also important that the vet carefully checks for any nail remnants left behind.
A torn, broken or split nail needs to be removed completely. No matter how loose it is, never do this without a vet giving sedation. It’s far too painful, and you run the risk of your dog never trusting you again if you try. Believe me, I’ve made this mistake.
Once again, the nailbed is best protected by a dressing. This can typically be removed after 3-5 days. Then to prevent it happening again, you need to start clipping the dewclaw. Here’s how…
How To Trim Dewclaws
Trimming dewclaws is a lot easier than clipping the other nails. Here’s a good ‘rule of thumb’:
- Run your finger under the nail: a dewclaw needs trimming when it catches or hooks your finger.
- Trim it back only until your finger slides off it easily. If you cut too far you will cause pain and bleeding.
- Use good quality bypass clippers and make a quick, precise and confident cut.
Is It OK To Remove Dewclaws?
Now look at the right hand top picture. It shows a dog who had his dewclaws removed by the breeder shortly after birth. I call this a form of mutilation.
Yes, I’m aware that some breed standards demand dewclaws be removed. Some breeders also have a strong tradition of removing them. However, we used to say the same thing about tail docking.
Dewclaws on the front legs are just as useful to a dog as their tail, and should be kept unless they cause problems. I’m perfectly happy to remove them if a dog keeps getting them torn despite good clipping. In 25 years, how many times do you think I’ve had to do this? Once.
Hind Dewclaw Removal
Hind limb dewclaws are another matter. If you look again at the left hand picture and compare it with the middle image you can see how they curl tightly. To make matters worse, they almost never contact the ground enough to wear them down. Often they even lack a bony connection.
So we have a nail that:
- Keeps growing regardless of exercise
- Gets ingrown when it gets long
- Is hard to trim without bleeding
- Is not part of normal anatomy
That’s plenty of justification for removal. I’ll support owners if they want to manage them, but most people eventually forget. Without constant vigilance, hind dewclaws get ingrown, painful and infected.
The best time to have them removed is together with desexing. It’s quick, easy, and goes well if they keep their collar on to prevent licking.
If an owner ever does ask us to take the front ones off, we put it down to receiving bad advice. It only takes a minute for them to agree that their dog is better off keeping these digits. Troublesome or not, maintenance of dewclaws is within the skillset of every dog owner.
Have something to add? Comments are welcome below and will appear within 24 hours.
By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. These help topics are from a series regularly posted on email and Twitter. Subscribe via email here to never miss a story! The information provided here is not intended to be used as a substitute for going to the vet. If your pet is unwell, please seek veterinary attention.