Osteoarthritis management

Introduction

Your pet has been diagnosed with osteoarthritis. While this is a progressive condition that currently has no cure, there are a lot of things that owners can do to help their pets. These can make a huge difference to their pain, exercise ability and quality of life. With the right management many arthritic pets can live a full and enjoyable life.

Weight control

Keeping weight within the normal range is the only thing that has scientifically proven in pets to slow progression of osteoarthritis and has also been conclusively shown to reduce severity of lameness. It is the single most important thing that owners can do to help. It has also been shown that compared with overweight dogs, those of appropriate weight, live on average two years longer. Some owners are literally killing their pets with “kindness”. Simple reductions in normal food and avoiding excessive treats is often all that is required,  but prescription diets are available from your vet for pets that struggle with weight control.

Exercise

Exercise is very important in arthritic dogs. Lack of exercise will lead to increased weight, muscle wastage and reduced joint range of motion. Appropriate movement actually helps nourish the remaining cartilage. However high intensity exercise such as ball games, prolonged rough play with other dogs or sudden changes in the amount of running can cause increased pain and potentially speed up deterioration of the disease. The general recommendation is to allow the maximum level of exercise that is tolerated on a regular basis. A period of lead walking at the beginning and end can help with warm up and warm down. Off lead exercise can be allowed but do not encourage your dog to over exercise. Throwing a ball will encourage your dog to continue to please you, even when pain has reached levels that he or she would have chosen to stop themselves. Try and keep exercise constant from day to day. Sudden long or strenuous walks can cause severe pain in dogs that are not used to it (osteoarthritic flare ups) but the same walk may be tolerated if the dogs is allowed to slowly get used to it. If lameness suddenly worsens (an osteoarthritic flare up) then exercise should be reduced to short (10-15 minute) lead walks for one to four weeks.

Off lead exercise should be encouraged but avoid high intensity activities such as ball games.

Drugs

Many osteoarthritic dogs and cats will require intermittent or regular use of drugs. The most commonly used type are non-steroidal anti-inflammatory drugs (NSAIDs) such as meloxicam, carprofen, firocoxib or robenacoxib. These medications work by reducing prostaglandin in and around joints. Prostaglandin is responsible for causing both pain and inflammation. NSAIDs can be used for short courses of days to weeks to treat osteoarthritic flare ups or on a daily basis to control long term pain. If using long term, then after the first four weeks these drugs can often be gradually reduced to the lowest effective dose, sometimes half or even a quarter of the recommended amount. They should never be given above the recommended dose. Most dogs and cats will tolerate these medications well, even if life-long treatment is required. In fact we would encourage the use of medications to allow pain free moderate exercise.  Some animals will not tolerate these medications and develop signs such as sickness or diarrhoea. They should be stopped immediately if these develop. These medications should also not be used in dogs with significant liver or kidney disease. A number of pure pain killer drugs can be used with or instead of NSAIDs if needed.

2D CT scan showing severely arthritic elbow

Oral Supplements

Despite claims by manufacturers, none of these have been conclusively shown to slow progression of osteoarthritis. These supplements are therefore mainly aimed at relieving symptoms. Two of the most commonly used are glucosamine chondroitin sulphate and essential fatty acids.

Glucosamine and chondroitin sulphate are building blocks of cartilage. Studies dogs show variable effectiveness, but there are some good human clinical trials which have shown similar benefits to NSAIDs. The onset is much slower. A minimum of six weeks should be given to assess a benefit and in some cases up to six months before deciding if it is working or not. As these are not classed as medicines,  quality control can be very variable. Analysis of some off the shelf products has shown a frequently lower content than on the label. Buying from a reputable source gives a better chance that you are administering the correct dose.

Essential fatty acids are most commonly fish oil derived, with Omega-3 fatty acids frequently present. Feeding high doses of Omega -3 fatty acids can reduce production of prostaglandin, which is a major cause of  pain and inflammation. These are included in some pet foods at increase doses. Hill’s j/d diet is one example. Two good quality trials in dogs with osteoarthritis showed this diet reduced pain and severity of lameness.

Giving a high enough dose of Omega-3 can be difficult. For a 30kg dog it has been recommended to give 3500mg / day of the two main forms EPA and DHA. A 1000mg fish oil capsule typically contains 300mg of combined EPA and DHA. Therefore 11.6 capsules would be needed per day.  Hills j/d and Royal canin JS for a 30kg dog would provide 1280mg EPA and DHA (4.5 capsules). But j/d  also contains other fatty acids which may have a benefit.

Green lipped muscle contains high levels of EPA and DHA. Royal canine JS is a green lipped muscle based diet. It has also been shown to reduce lameness in osteoarthritic dogs. Studies showing a benefit used high does 20mg/kg/day. One study which used lower doses 11mg/kg showed no benefit.

Antinol is a recent green lipped muscle extract product. Early studies show possible benefit but this is based on small numbers in trials.

Rosehip has been used in small trials in humans and suggests some improvement in pain and stiffness. There are no trials in dogs and cats.

Tumeric (Curcumin). Human and cow laboratory studies show some anti-inflammatory properties. Dog absorb this substance poorly compared to humans and there are no convincing veterinary trials showing a benefit.

Injectable Supplements

Pentosan polysulphate (“Cartrophen” / “Synovan”) is commonly given to try and alleviate symptoms of osteoarthritis in dogs. It is supposed to reduce inflammation and potentially increase joint lubrication. Many vets feel it is effective in reducing pain and lameness, though the results of limited clinical trials are inconclusive.

Summary

There is no one treatment that will cures an osteoarthritic dog or cat. The key to success is understanding that there are numerous things owners can do in the life-long management of this condition. Many animals have arthritis and are enjoying full and active lives.