Osteoarthritis (aka, "arthritis") is a very common disease of dogs and cats. It is known to affect one in five dogs and, according to one study, as many as 98% of all cats over the age of twelve.
The condition we generally refer to as arthritis is a joint problem characterized by a pain upon movement due to the thinning of joint cartilage (the protective lining of bones that serves as a cushion for ease of movement), fluid accumulation within the joint, and the formation of bony growths as a result. Typically observed in older dogs and cats, arthritis can by caused by injury, infection, the body's immune system, degenerative diseases or conformational disorders.
The most common form of arthritis is called osteoarthritis or degenerative joint disease. The remainder of this article will detail this latter process, which is caused by the degenerative process of aging, often in concert with conformational diseases like hip dysplasia, elbow dysplasia, intervertebral disc disease, and medial patellar luxation.
Symptoms and Identification
Signs of arthritis include stiffness after exercise, muscle atrophy, reduced mobility, swelling of the joints, difficulty rising, jumping and/or climbing stairs, and possibly even a grating sound in the joints.
The trouble with identifying osteoarthritis in most dogs and cats is that osteoarthritis typically comes on slowly and dogs only rarely complain about their aching joints. Further, most owners assume that the standard signs of osteoarthritis are "normal" in older pets and, therefore, are less noteworthy.
Routine veterinary visits are the first line of defense when it comes to diagnosing the disease early on. Radiography (x-rays) can then reveal the characteristic bony growths, internal joint swelling and other joint changes we expect from dogs and cats with osteoarthritis.
In some cases, arthroscopic surgery is undertaken as part of the diagnostic process. Some pets may even require open-joint surgery to assess the extent of the damage, even as it's being repaired.
Though osteoarthritis can affect any breed of dog or cat, some breeds -- especially large and giant breeds or breeds predisposed to specific joint diseases -- are overrepresented. Larger dogs and cats of mixed breeds are more likely to suffer from osteoarthritis.
Osteoarthritis treatment will often vary depending on the cause of the disease -- everything from mild drug therapy to surgery for dogs and cats with conformational disorders like hip dysplasia and medial patellar luxation or who suffer degenerative disorders like intervertebral disc disease.
Nonetheless, the most common mode of intervention for canine patients involves non-steroidal anti-inflammatory (NDAID) drug therapy. While most dogs are good candidates for the extremely beneficial effects of these drugs, few drug options are available for cats with arthritis.
Drugs like corticosteroids and opiates are often prescribed as well -- some even in concert with NSAID therapy (note: corticosteroids are never to be administered concurrently with NSAIDs!).
Nutraceuticals like glucosamine and fatty acids have been shown to be of some benefit, albeit limited. Alternative therapies, such as stem-cell therapy, laser treatments, and acupuncture, are also available for pet owners who choose to attempt less conventional approaches to management of osteoarthritis symptoms.
Osteoarthritis doesn't have to be very expensive if owners focus on prevention (see the following section).
Mildly affected pets may only require x-rays on occasion and medication on a daily or occasional basis.
Moderate to severely affected pets, however, may require surgical intervention and/or multiple, potentially expensive drugs to help minimize stem the tide of continued arthritis development and assuage the pain associated with it.
For osteoarthritis requiring more assiduous intervention, the cost of diagnosis and treatment depends on many factors, including the cause of the disease, degree to which the disease is amenable to medical vs. surgical intervention, geographic location (cost of living), standard of care (lower vs. higher standards of veterinary care), whether specialty hospitals are employed (higher quality equipment, certified personnel, and board-certification for veterinarians specialized in the fields of surgery, neurology, and internal medicine).
There is no direct mode of prevention for most of the conditions that lead to osteoarthritis. Consequently, genetic counseling to advance the sterilization of affected animals and their first-degree relatives (parents and siblings) is a fundamental approach to limiting the inheritance of the genetic material responsible for heritable conditions known to result in osteoarthritis.
However, regular, moderate exercise and maintaining a normal weight will almost certainly help delay the symptoms of osteoarthritis. Some studies in dogs suggest that nutritional supplements may help reduce the radiographic (x-ray) signs of arthritis in dogs.
Early diagnosis is part of any preventative process given that arthritis is a progressive disease that has more treatment options available to patients who are diagnosed earlier.
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