The Purpose of the Dew Claw on Dogs

Many American dog breeders advertise their puppies as having their dew claws removed. The dew claw is a nail on the inside of the dog's front leg and corresponds to the position of a human thumb. Some dogs also have dew claws on their hind legs or multiple dew claws on each leg. Although dew claws are commonly removed to prevent injury, they provide support in some dogs.

  1. Purpose

    • Dew claws are considered vestigial digits -- that is, they were once important to the early ancestors of dogs, but their importance has decreased over time. Early dogs may have had five toes, explains Jeff Van Dalsum of Perfect Puppy Care. The legs lengthened and the feet narrowed to four toes for improved running ability. The dew claw is a remnant of the lost toe. A few dogs can lightly grasp chew toys and treats using dew claws. Dew claws rarely touch the ground unless the dog is galloping or cantering. In this case, the dew claw provides support for the leg and keeps it from twisting as the dog turns.

    Anatomy

    • The dew claw is connected to five tendons. The tendons connect to muscles in the dog's legs. Front dew claws are more firmly attached than rear ones. Rear dew claws are usually connected by a thin flap of skin, while front ones may have phalanx bones.

    Care

    • The dew claw needs to be clipped or trimmed more often than other nails because it rarely comes into contact with the ground. Dew claws cause discomfort to dogs if allowed to grow too long. The dew claw can snag on carpet, toys or furniture and rip off. Hunting and sporting dogs that run through thick bush are especially at risk for accidentally tearing off dew claws. Veterinary attention is needed to repair the damage and prevent infection if the dew claw is severed.

    Removal

    • Dew claws are often removed to prevent problems. It is best to remove the dew claw when the puppy is 3 to 5 days old. The risk of complication is reduced because the puppy is a given local anesthesia instead of general anesthesia. Removing dew claws in older dogs is more expensive, difficult and painful. An older dog will need more post-operative care than a 3- to 5-day-old puppy.