Study shows why you shouldn’t declaw your cats

Having your cats declawed could increase their risk of long-term or persistent pain, and might even make them more aggressive and less likely to use the litter box, according to new research published online Tuesday in the Journal of Feline Medicine and Surgery.

As part of the study, lead author Nicole Martell-Moran, a veterinary practitioner at the Feline Medical Center in Houston, Texas, and her colleagues looked at a total of 137 cats that had not undergone the procedure known as onychectomy, and another 137 which had (including 33 that had the claws removed on all four feet).

Each of the cats were examined for signs of discomfort and barbering (or excessive licking or chewing of fur), and their medical history was reviewed for negative behaviors. What the study authors found was that declawed cats were approximately seven times more likely to urinate or soil outside of the litter box, four times more likely to bite, and three times more likely to either become aggressive or overgroom themselves.

Furthermore, the declawed felines were nearly three times more likely to be diagnosed with back pain than cats that had not undergone onychectomies, the study authors said. This is likely due to shortening of the declawed limb, altered gait and/or chronic pain at the site of the procedure.

“The result of this research reinforces my opinion that declawed cats with unwanted behaviors may not be ‘bad cats,’ they may simply need pain management,” Martin-Moran explained in a statement. “We now have scientific evidence that declawing is more detrimental to our feline patients than we originally thought and I hope this study becomes one of many that will lead veterinarians to reconsider declawing cats.”

Even proper onychectomy technique can lead to problems

Of the cats involved in the study, 176 were cared for by owners, the researchers said. Eighty-eight of those were declawed, and 88 had not been declawed. Ninety-eight of the cats studied were shelter cats (49 clawed, 49 declawed). Two years worth of their medical histories were reviewed, and all declaw cats were radiographed for distal limb abnormalities.

Martin-Moran and her colleagues found “significant increases” in the risk of back pain, biting and barbering in declawed cats, and nearly two-thirds (63 percent) of the declawed cats showed radiographic evidence of residual bone fragments in their third phalanx (P3). Those cats which retained P3 fragments were more likely to experience back pain, aggression or elimination issues than those whose P3 fragments were completely removed.

“Optimal surgical technique, with the removal of P3 in its entirety, was associated with fewer adverse outcomes and lower odds of these outcomes, but operated animals remained at increased odds of biting and undesirable habits of elimination compared with non-surgical controls,” the authors reported. “The use of optimal surgical technique does not eliminate the risk of adverse behavior subsequent to onychectomy.”

The reason for these behaviors, the researchers explained in a statement, is that removing the distal phalanges (P3) forces the cat to place additional weight on the soft cartilaginous ends of the middle (P2) phalanges. Discomfort in those phalanges leads the cat to urinate or defecate on softer surfaces, such as a carpet, rather than the gravel-like surface in a litter box. Furthermore, cats that have been declawed are more likely to bite as due to their law of claws for self-defense, and this could be potentially harmful to their owners.