Arthritis is defined simply as the inflammation of a joint. In dogs, this term tends to refer to osteoarthritis ("OA," also called degenerative joint disease, or "DJD"). Osteoarthritis is a syndrome characterized by bone remodeling, low-grade inflammation and degenerative, progressive and permanent deterioration of the articular cartilage of joints.
Causes & Prevention
Causes of Arthritis in Dogs
Some dogs develop osteoarthritis as a primary condition, with no apparent cause. This is uncommon. Most cases of OA are secondary to some other initiating cause or condition. Acute or chronic trauma, or some other form of injury to a joint, causes the release of a number of inflammatory mediators that essentially degrade the cartilage matrix faster than it can be re-synthesized. They also cause pain. The inciting events usually fall into one of two categories: either abnormal forces imposed on normal joints (fractures, sprains, obesity, etc.) or normal forces imposed on abnormal joints (elbow or hip dysplasia, osteochondrosis dissecans ["OCD"], patellar luxation, cranial cruciate ligament rupture or tear, or other congenital or genetic conformational defects). Regardless of cause, the ultimate effect of OA is the same: pain and loss of normal function of the affected joint.
Preventing Arthritis in Dogs
Osteoarthritis is almost always progressive and irreversible. Since the cause of primary OA in dogs is not known, prevention is not really possible at this time. However, the progression of secondary OA may be delayed by early identification and treatment of the predisposing cause. Weight management is perhaps the most important factor in preventing or delaying the progression of osteoarthritis in domestic dogs. Overweight dogs should be put on a calorie-restricted diet under a veterinarian's supervision. A number of prescription and over-the-counter medications and supplements are available to address the inflammation and pain that accompany this disease and may help prevent further joint damage. Owners should always provide their dogs with soft, comfortable and well-padded sleeping areas and should take reasonable measures to restrict jumping, leaping off of high places and other activities that might predispose limbs to acute or chronic trauma. Regular, moderate, low-impact activities also can be very helpful by strengthening the musculature surrounding at-risk joints.
Although osteoarthritis is a progressive, painful and incurable condition, both surgical and medical therapies, together with life-style changes, typically allow affected dogs to enjoy a good quality of life.
Symptoms & Signs
Arthritis is a painful, progressive and irreversible condition that unfortunately is very common in dogs and in people. Its common definition is inflammation of any joint, and it can be caused by a number of things. Medically, arthritis is the degenerative, progressive and permanent deterioration of the articular cartilage of joints. While most commonly seen in older dogs, arthritis can strike younger pets as well, especially those with a genetic predisposition to developing the disease. There are a number of medical treatments and therapies that can prevent further damage to the joints and can reduce, or eliminate, painful flair-ups from this condition. The clinical signs of arthritis in dogs usually appear gradually and then worsen over time. The first signs of arthritis are often so mild that even the most vigilant of dog owners will miss them. How rapidly the disease progresses depends upon a number of factors, including the breed of the dog, overall nutrition, weight, age and genetics.
Symptoms of Arthritis
The signs that owners may notice in their dogs that are developing arthritis are not specific to this disorder. However, taken together, the various symptoms will be suggestive of arthritis to the observant owner. These include:
Reluctance to rise or ambulate
Stiffness (especially after vigorous exercise or prolonged periods of rest)
Visible joint deformities
Prolonged sleeping time
Aggression when touched
Disinterest in physical activity
Lack of appetite
Abnormal stance when walking; pelvis tucked under, using hind legs with great care
Affected dogs may rise more slowly in the morning and take longer to warm up later in the day. They may spend more time resting or sleeping, which can lead to weight gain and exacerbate the effects of the disease. Dogs that suffer from arthritis may be depressed and lethargic. They often become irritable or even aggressive when approached or touched, and they may stop eating. A characteristic stance of dogs with severe OA is walking with their pelvis tucked underneath them, using their hind legs with exaggerated care. If a single joint is affected, the animal may become "three-legged lame," which will predispose the joints in the other limbs to developing OA, because they will be carrying more weight than normal. Dogs that suffer from severe arthritis may become depressed. They can become aggressive if touched or petted, and they may even stop eating. A characteristic stance of dogs with severe arthritis is walking with the pelvis tucked in, using the back legs with exaggerated care. If the arthritis is restricted to one joint, the dog may limp or hold the leg up, or may walk or run using the other three legs. In these instances, arthritis will worsen in the other limbs because they are carrying more weight than normal.
Dogs At Increased Risk
There is no breed or gender predisposition in dogs to the development of this condition, but it most commonly affects older dogs.
Diagnosis & Tests
Arthritis in dogs, or Osteoarthritis (OA), is extremely common in domestic dogs. It is not particularly difficult to diagnose. While it cannot be "treated" or reversed, there are a number of things that owners can do to manage the disease in their dogs. In most cases, owners notice that their aging dogs are lame, reluctant to rise, and just generally slowing down. Those are all signs of osteoarthritis.
How Arthritis is Diagnosed
The usual initial data base for most canine patients includes blood work (a complete blood count and a serum biochemistry panel) and a urinalysis. Those tests do not provide any diagnostic information about the condition of dogs with arthritis. A complete physical examination will help to localize the site of joint pain. Radiographs (commonly known as x-rays) are an effective way to assess changes in the joint capsules, soft tissue thickening, narrowing of joint spaces, cartilage changes, bone changes, mineralization of soft tissues, intra-articular calcified bodies and other physical changes associated with arthritis. Unfortunately, the degree of abnormalities seen on radiographs does not necessarily correlate to the severity of clinical disease. Another procedure, called bone nuclear scintigraphy, can help localize degenerative joint disease as well. Sampling of the synovial fluid (the fluid lining the joint capsule) can help assess the degree of inflammation, and whether any infection is present. Magnetic resonance imaging (MRI) and computed tomography (CT) are also available to assess the nature or degree of osteoarthritis.
Osteoarthritis in dogs is almost always irreversible and progressive. However, there are ways to manage this condition and maintain affected dogs' quality of life.
When an owner suspects that her dog is suffering from arthritis – which usually will be seen in aging animals – it is time to get a veterinarian's assessment of the dog's health and physical status. This is a painful condition, and there are medications and supplements that can alleviate much of the pain. The therapeutic goals for treating osteoarthritis are to alleviate pain, improve mechanical joint function, slow the progression of the disease and facilitate repair of the affected joints if at all possible.
Treatment Options for Arthritis in Dogs
Surgical and non-surgical procedures are available to address canine arthritis. These procedures potentially can dramatically improve a dog's quality of life. However, surgery is usually a last resort, as the consequences of surgery can include pain and other debilitating symptoms that are already associated with the disorder.
Non-surgical treatment options include administration of nonsteroidal anti-inflammatory medications (NSAIDs), chondroprotective agents to promote heathy cartilage repair (polysulfated glycosaminoglycans, glucosamine, chondroitin sulfate, hyaluronan, Vitamin C,omega 3 and 6 fatty acids and MSM, among others) and/or opioids. These medications and supplements can be quite effective in reducing inflammation and relieving pain. In many cases, good dietary management and weight loss alone can dramatically reduce the pain and other symptoms of arthritis, as overweight dogs tend to suffer more than do fit dogs. Moderate, regulated exercise and/or exercise restriction can stimulate cartilage health and help delay joint degeneration, and long controlled walks in early or mild cases of osteoarthritis may help delay atrophy of muscle mass, as well. Physical therapy, hydrotherapy (swimming and other water exercises), passive flexion and extension of the affected limbs and controlled low-impact on-leash walks often are incorporated into the management process for dogs with osteoarthritis. The attending veterinarian is the best one to discuss these possible treatment and management techniques with the dog's owner.
Other less traditional techniques that may benefit affected dogs, in addition to medical treatment, might include: massage therapy to stimulate blood flow and reduce pain and inflammation, possible application of acupuncture and/or acupressure techniques; use of herbal or other non-regulated supplements or homeopathic "remedies"; and other forms of supportive care that may help to ease pain, increase circulation, speed healing and otherwise promote wellness, relaxation and comfort. Some of these adjunct approaches lack controlled studies of their effectiveness and may not have established quality control methods or ways to assess their benefit to dogs with osteoarthritis or other forms of degenerative joint disease.
When non-surgical treatment options for arthritis are unsuccessful, such as when the dog's joints have become so severely damaged that non-surgical treatment options are not helping resolve the dog's pain, there are surgical options to consider. These include arthroscopic surgery, joint replacement, joint repair and joint fusion. More treatments possibilities are constantly under development.
Arthroscopy is the most minimally-invasive joint surgery currently available for dogs with arthritis. This procedure can be used to help resolve damage in shoulders, elbows, the stifle (knee) joint in the rear legs and the ankle bones. The procedure uses small cuts over the joint to insert cameras and uses small instruments to assess joint damage and plan joint repair. In some cases, arthroscopy cannot be performed due to swelling or leakage from the joint. In those cases, open surgery may be necessary to assess and/or repair the joint.
Elbow and hip replacements are now available for dogs. These are intensive and expensive surgeries which require a long recovery time (approximately 2-3 months). However, over 90% of these surgeries are successful in resolving the clinical signs of arthritic joints. Joint fusion is a surgical procedure which uses metal implants to fuse damaged joints. This procedure can be used on the wrists, fingers and back of people, and the comparable areas of our companion animals. Fusion repairs in dogs using bone grafts and artificial mediums are currently being studied. There are complications to this surgery, most often involving the metal implants themselves, and the recovery time can be quite long.
Most dogs with arthritis are overweight and/or elderly. These dogs are not good surgical candidates. The risk of surgery for these dogs is high, so it is important for pet owners to have an upfront talk about these risks with their veterinarian before deciding to go through with a surgery. Arthritis surgery is not always successful, and veterinarians can usually give pet owners an idea of what they can, and cannot, expect from the surgery.
Prognosis for Dogs with Arthritis
Osteoarthritis is a progressive and irreversible disease. Surgical correction is sometimes possible. Medical treatment is also available to relieve the pain associated with this condition. Together, these treatment options can help affected dogs maintain a good, normal quality of life. However, they cannot "cure" arthritis.