Inflammation within the joints, osteoarthritis, is common in dogs with about 20% suffering the effects. It is a slowly evolving disease with development of joint pain, stiffness and limitation of motion. The most common cause is abnormal stresses on normal cartilage. Even tiny imperfections in the joints can lead to mechanical breakdowns and the resultant inflammation. The progression of the disease can be affected by body weight, amount of exercise and genetic influences.
The first symptom is loss of normal performance followed by stiffness after rest that usually lasts only a few minutes. Next, quality of life is affected – decreased exercise tolerance, not getting in or out of the car without help and decreased activity. These problems are frequently blamed on the pet’s increasing age. Progressive disease leads to lameness of a sudden or slow development. In some dogs there may be behavioral effects of joint discomfort including nervousness, aggression, depression and loss of appetite.
There is no cure for osteoarthrosis but rather the progressive condition is “managed.” In dogs the therapy goals are influenced by the severity of the symptoms, the intended activity, age and size and any concurrent disease or drug therapy that may interfere with the use of anti-inflammatory drugs.
The most important treatment in overweight pets is weight loss. Obese dogs can become free of symptoms once they have achieved ideal body weight or be managed with lower dosages of pain relieving and anti-inflammatory medications.
Medical therapy will vary depending on the severity and location of the osteoarthritis. With medical therapy it is most effective as multi-modal treatment (2 or more different types) and best started prior to development of chronic pain. Once chronic pain is established medical therapy is generally not as effective. Similarly pharmaceuticals should be given regularly and not “as needed” after the pain worsens.
In most patients unless the osteoarthritis is mild the use of a non-steroid anti-inflammatory drug (NSAID) is indicated. These drugs while not addressing the underlying cause do control pain and inflammation allowing improved mobility. The most commonly used are referred to as COX enzyme inhibitors. COX enzymes are used by the body to produce prostaglandins. The “bad” prostaglandins cause inflammation and the “good” prostaglandins protect the stomach. This is in part why some patients can have stomach upset with the COX enzyme inhibiting non-steroidal anti-inflammatory drugs. A newer drug called grapiprant (Galliprant®) does not inhibit the COX enzymes but works by blocking the inflammation and pain producing prostaglandin receptor. For those who have digestive issues with other non-steroidal anti-inflammatory drugs they generally do well with grapiprant.
A pain relieving drug, Gabapentin, is generally very effective combined with an NSAID or sometimes used alone in mild cases. It is particularly helpful in dealing with chronic or neuropathic pain. It is generally started at a low dose and the dosage gradually increased to avoid the common side effect of sedation. It may not be helpful in patients until a high dosage is reached. The medication is safe for long-term use.
Opiates particularly Tramadol can provide pain relief and are generally well tolerated. There appears to be individual variation in responsiveness to these medications and with chronic pain full effect may not be seen until after 2 weeks. Due to potential changes in alertness and behavior, Tramadol may not be good for working or service dogs, and check with your veterinarian before using with anti-anxiety medications.
Adequan® is an injectable glycosaminoglcin which is a major component of joint cartilage. The specific mechanism of action in dog joints is unknown. It is perhaps best used when the osteoarthrosis is at an early stage and when used alone at this time many clients report significant improvement in mobility.
In regards to glucosamine, chondroitin sulfate and green lipped mussel, there are no studies to document effectiveness other than those conducted by the manufacturers. Unlike an injection of Adequan®, since these products are given orally they may be degraded to other compounds by the stomach and digestive enzymes prior to absorption. Since these products are not regulated as pharmaceuticals the actual quality of these products varies widely. Cosequin® manufactured by Nutramax Labs is a reputable product.
For those patients that are not responsive to previously reviewed medications the injection into the joint(s) of hyaluronic acid or corticosteroids or the use of PRP (platelet rich plasma) is indicated. Hyaluronic acid is a form of viscosupplementation which restores the physical properties of the joint fluid to aid in the lubrication of the joint, decrease inflammation and degradation, and help in cartilage repair. Used alone it is useful for mild to moderate osteoarthritis but in severe cases it is used with corticosteroids or PRP. Corticosteroid injections into the affected joint(s) reduce inflammation and improve comfort with 2 injections separated by 3 weeks lasting weeks to months. PRP reportedly has an anti-inflammatory and analgesic effect; has cartilage protective effects and improves the viscoelastic properties of joint fluid. For most patients joint injections require sedation.
Fish oil (omega-3 fatty acids) does have documented effectiveness and generally supplemented at 600mg per day.
Besides medications and supplements there are lifestyle changes that can be beneficial. Regular moderate exercise including leash walking and swimming reduces inflammation and maintains good muscle strength to stabilize joints (“motion is the lotion”). Passive range of motion exercises; massage and hydrotherapy with an underwater treadmill or deep water therapy are all valuable. A warm, well padded, e.g. orthopedic foam bed, area to sleep is also important
For most dogs symptoms associated with osteoarthrosis can be relieved with weight loss if needed, exercise in moderation and pharmaceuticals with fish oil supplementation. Your veterinarian can help with catching early signs of this disease and guiding you with preventative treatment and therapies to delay progression of arthritis and if needed medications to relieve the debilitating pain associated with osteoarthritis.