As a veterinary sports medicine specialist, I work extensively with canine athletes, developing rehabilitation programs for injured dogs or dogs that required surgery due to performance-related injuries. I have seen many dogs, especially field trial/hunt test and agility dogs, that have chronic carpal arthritis, frequently so severe that they must be retired or at least carefully managed for the rest of their careers. I noticed that very few of those dogs had dewclaws and began to wonder whether these appendages might, in fact, protect a dog from injuries. What I learned might surprise you.
The Anatomy of Dewclaws
Miller's Guide to the Anatomy of the Dog, a veterinary anatomy text, has an excellent figure depicting the muscular anatomy of the distal forelimb. There are 2 functional muscles, the extensor pollicis longus et indicis proprius and flexor digitorum profundus, which are attached to the front dewclaw by 4 tendons (Figure 1). Each of those muscle/tendon units has a different function in movement. That means that if you cut off the dew claws, you are preventing the muscles that were attached to the dewclaws from functioning.
In contrast, rear limb dewclaws do not have muscle/tendon attachments, so their removal might be appropriate, except in the breeds such as Briards and Beauceron in which they should be retained.
CHRIS ZINK DVM PhD DACVP DACVSMR CCRT CVSMT CVA is one of the world’s top canine sports medicine and rehabilitation veterinarians.