Onychectomy
Onychectomy, popularly known as declawing, is an operation to remove an animal's claws surgically by means of the amputation of all or part of the distal phalanges, or end bones, of the animal's toes. Because the claw develops from germinal tissue within the third phalanx, amputation of the bone is necessary to fully remove the claw. The terms onychectomy and declawing imply mere claw removal, but a more appropriate description would be phalangectomy, excision of toe bone.
Although it has been somewhat common in Canada and the United States, declawing is considered an act of animal cruelty in many countries, as it causes physical and psychological suffering to the animal.
Medically indicated onychectomy
Onychectomy can be a treatment for comminuted fractures, pseudarthrosis, intraarticular fractures, irreparable luxation, neoplasia, and chronic infections.Elective onychectomy
Elective onychectomy is usually done on all toes on the front paws. Sometimes the rear paws are declawed as well.Despite the fact that it is a surgery without medical cause, in some parts of the world, particularly in Northern America, declawing was for many years a relatively standard practice, and "surveys of routine elective procedures" in 1988 and 1996 showed it was performed along with neutering in more than 20% of cases.
Although increasingly controversial, when the procedure is presented and perceived as mundane and innocuous, non-medical reasons for this procedure can be convincing:
Risks from scratching
Data on relinquishment to shelters indicate that many owners relinquish cats who engage in unwanted scratching. For example, a survey of veterinarians in Brazil reported scratching as the second-most-given behavioural reason for abandonment of cats.While sometimes framed as concern for household possessions, people are indeed concerned with pain and infection, although the U.S. Centers for Disease Control do not recommend declawing, even for felines in contact with immunocompromised humans.
Methods
Despite the prevalence of elective onychectomy in North America, no standard practices exist regarding the surgical techniques or surgical tools used, the administration of post-operative analgesics or other follow-up care, or the optimal age or other attributes of cats undergoing the procedure. There are three surgical methods: scalpel blade, guillotine trimmers, and laser.No technique or method has been proven to eliminate the many complications associated with declawing. The International Society of Feline Medicine states that "Even if future improvements in surgical techniques can negate some of the adverse effects associated with declawing, iCatCare and ISFM believe this procedure is unethical other than if required to manage a medical condition and should be banned."
Recovery, health and behavioral effects
Onychectomy is an orthopedic surgery involving one separate phalangeal amputations, which requires general anesthesia and multi-modal pain management before, during, and after surgery.A 2018 study by Martell-Moran, et al. found, in a study of 274 cats, that "declawing cats increases the risk of unwanted behaviors and may increase risk for developing back pain. Evidence of inadequate surgical technique was common in the study population. Among declawed cats, retained P3 fragments further increased the risk of developing back pain and adverse behaviors. The use of optimal surgical technique does not eliminate the risk of adverse behavior subsequent to onychectomy." The study found that inappropriate toileting, biting, aggression and overgrooming occurred significantly more often in the declawed cats than the non-declawed cats. A declawed cat was also almost three times more likely to be diagnosed with back pain than a non-declawed cat.
In a survey of 276 cat owners, 34% reported post-surgical discomfort in their cats while 78% reported primarily tenderness. Recovery time took from three days to two weeks. Increased biting strength or frequency was reported in 4% of cats, but overall, 96% of owners were satisfied with the surgery. Some other studies found lameness after onychectomy lasting >3 days, >1 week, 8 days, > 12 days, 180 days, and 96 months.
At one veterinary teaching hospital, between 50 and 80% of cats had one or more medical complications post-surgery; 19.8% developed complications after release. Other studies have reported medical post-op complication rates as 24%, 53%, 1.4%, 82.5% for blade and 51.5% for shear technique, and 80%. Reported medical complications include: pain, hemorrhage, laceration of paw pads, swelling, reluctance to bear weight on affected limb, neuropraxia, radial nerve damage, lameness, infection, abscess, tissue necrosis, wound dehiscence, incomplete healing, protrusion of 2nd phalanx, claw regrowth, scurs, retention of flexor process of third phalanx, chronic draining tracts, self-mutilation, dermatitis, lethargy, palmigrade stance, chronic intermittent lameness, chronic pain syndrome, flexor tendon contracture, and cystitis. Claw regrowth has been seen by veterinarians anywhere from weeks up to 15 years after onychectomy.
In post-operation follow ups Yeon, et al. found six of thirty-nine cats were house soiling and seven had increased biting frequency or intensity. The authors concluded based on this and previous studies that "behavioral problems following onychectomy were not pronounced". Follow-ups in this study were conducted an average of eleven and a half months after surgery.
Behavior problems are a primary cause of cats being relinquished to shelters. Proponents of declawing argue that declawing reduces undesired behaviors and thus reduces the likelihood of relinquishment. Opponents of declawing argue the surgery itself creates more behavioral problems leading to relinquishment of cats. A study by Patronek et al. found in a univariate analysis that declawed cats were only 63% as likely to be relinquished as non-declawed cats. A multivariate analysis conducted in the same study shows odds of being relinquished to a shelter were 89% higher for declawed cats. The authors concluded that the conflicting results of the two analyses made it difficult to interpret the effects of declawing. In a shelter setting, more declawed cats were reported by their owners to have problems with inappropriate elimination. However, this study ultimately found no association between the declaw status of cats and their aggression towards humans or frequency of inappropriate elimination.
In another study, 16% of declawed cats developed behavior problems, and more declawed than clawed cats were referred to a vet teaching hospital for behavior problems. This was the second-longest follow-up period ever examined.
Patronek, Glickman and Beck found no association between the declaw status of cats and the frequency of inappropriate elimination.
In another study of 275 cats, 11 cats developed or had worse behavior problems post-declawing; 5 clients reported that their cats had developed litterbox and biting problems.
Chronic pain syndrome of onychectomy has been described by a pain management specialist as leading to unwanted behaviors, including increased aggression.
A prospective study comparing declawing with tendonectomy noted many medical as well as behavior complications.
An internet survey found that declawed cats were more likely to jump on tables and counters and house-soiled more than non-declawed cats.