Onychectomy (declawing) is a procedure performed in the United States and Canada to prevent cats from scratching and destroying property. As of June 2016, no studies incorporating modern pain assessment tools to evaluate patient pain following declawing could be found in a PubMed search.
This studys primary purpose was to determine any association between onychectomy, back pain, and adverse behaviors (eg, biting, aggression, inappropriate elimination, barbering [excessive licking or chewing of fur]). Another purpose was to identify the prevalence of P3 fragments remaining after declaw surgery and determine whether P3 fragments were associated with adverse effects when compared with declawed cats without P3 fragments.
This study included 274 cats137 cats had been declawed and 137 were not declawed. Each group consisted of 88 client-owned cats and 49 shelter cats. A single investigator examined each cat and assessed 2 years of medical history with respect to the declaw method used and the presence of back pain and adverse behaviors. Radiographs of declawed limbs were obtained and reviewed by a board-certified radiologist.
Statistical analysis indicated that the likelihood of back pain, periuria/perichezia, aggression, and barbering was significantly increased in declawed cats vs nondeclawed cats. Radiographic evidence of residual P3 fragments was found in 63% of declawed cats. Back pain, inappropriate elimination, biting, aggression, and/or barbering occurred more often in cats with retained P3 fragments, whereas only increased biting and inappropriate elimination habits were seen in cats without retained fragments.
The authors concluded that a clear association exists between declawing and the presence of deleterious side effects after a typical postoperative period, and that the prevalence of P3 fragments in declawed cats was excessive and surprising. The study showed persistent pain and discomfort following declaw surgery is an important risk factor for behavioral changes.