Cat Diseases & Illnesses – Osteoarthritis
Arthritis (also called osteoarthritis or degenerative joint disease (DJD)) has been well recognised in people and dogs for a long time, but has been greatly under-diagnosed in cats. Studies done estimate that up to 80-100% of catsover the age of 10 years have signs of arthritis on X-ray. Arthritis is more easily missed because cats are very good at hiding their pain and may simply reduce their movement, become quieter, or hide. They are also not taken for walks on a regular basis, so lameness or reluctance to exercise is often not noticed.
In arthritis, the protective layer of cartilage lining the joint, that usually helps to allow smooth movement of the joints, is damaged and worn away, and the joint fluid becomes less effective in providing joint lubrication. The bone becomes exposed, causing pain and inflammation. Arthritis is a progressive disease – it cannot be ‘cured’ and will worsen over time but there are ways to manage it. The aim of treatment is to reduce your cat’s symptoms and improve their comfort and mobility.
The most common causes of arthritis in cats include:
Age-related wear and tear of the joint
Traumatic injury to the joint or bone such as a fracture (as the fracture heals it may result in abnormal weight loading through the joint)
These can include reduced activity and hiding away. You may notice reluctance to jump up onto surfacesor your cat starting to struggle with the cat flap. Cats that previously roamed outdoors might start to stay closer to home.
You may also notice them starting to develop a matted coat as cats with arthritis loose the flexibility needed to groom thoroughly. They may require help to keep their coats in good condition, so regular grooming at home is important. Discomfort over the back and hips when grooming can also indicate the presence of arthritis.
Behavioural changes indicating discomfort might also be noticed, such as aggression when handled
This is often based primarily on your history and the clinical signs you may have seen at home. Your vet will also perform a thorough clinical examination and findings such as swollen or painful joints, reduced movement on joint manipulation, and reduced muscle mass, are suggestive of arthritis. Sometimes, your vet might also confirm the presence of arthritis with X-rays: soft tissue swelling around the joint, uneven new bone growth around the joint ‘osteophytes’, joint thickening and an irregular joint surface would all be confirm the presence of arthritis.
This consists of many different aspects that work together to slow progression of disease. The earlier treatment is started, the better:
Ensuring your cat is not overweight is the most effective way of slowing down arthritis. It reduces strain on arthritic joints, the severity of clinical signs, and can make it easier for them to get around. Animals with joint disease have less ability to exercise, which should be considered when feeding them. Weight control can be achieved with a calorie controlled diet and owners must be strict with treats.
If your cat is struggling to groom themselves then you may need to help them do this. Similarly if they struggle to get into the litter tray then you may need to change to a lower sided tray and make sure that food, water and soft bedding is all easily accessible. Sometimes it can help to slightly elevate their food bowl so they don’t have to bend as much to eat, as this can be uncomfortable.
Specific prescription diets designed for cats with arthritis include Royal Canin Walthams Feline Mobility. These diets contain beneficial essential fatty acids and antioxidants to help the joints and are also lower in calories to help weight control.
Supplements including glucosamine and chondroitin sulphate can really improve arthritis. They should be used longer-term, and several weeks of administration may be needed before improvements are noticed at home. Glucosamine is one of a group of molecules called glycosaminoglycans and these are the building blocks of cartilage. Chondroitin inhibits destructive enzymes in the joint and supplementation can help protect the cartilage and slow progression of arthritis. These compounds are available in products such as Synoquin, Seraquin, Flexadin and Cosequin and have become a mainstay of arthritis management. When these are used alongside anti-inflammatory drugs (discussed below), lower doses of the drugs can be used, minimising side effects.
- Anti-inflammatory medications: The most common class of drugs used in OA are the Non-Steroidal Anti Inflammatory Drugs (NSAIDs). Meloxicam (Metacam, Meloxidyl) will often be prescribed; this comes in a liquid form. Meloxicam helps to reduce inflammation, swelling and pain in the affected joints, improving mobility and comfort levels. It should be administered with food and the dose required will be determined by your vet. There are potential side effects on the gut, kidneys and liver and your vet may wish to do occasional blood tests to monitor these.
- Additional pain relief medications: If you are unable to give NSAIDs to your pet (for example due to other medications they are also on, other diseases they have (such as kidney disease in older cats) or unacceptable adverse side-effects), or NSAIDs alone are not adequately controlling your pet’s comfort levels, your vet may advise some other pain relief medications such as Tramadol. This is not actually licensed for use in animals, so other options are usually explored first.
This can be a useful adjunct to other treatments in some cats if they will tolerate it, but should be discussed with your vet first. Always ensure it is done by a certified veterinary acupuncturist. It will usually involve a course of several sessions, weekly to begin with then further apart. Top up sessions can then be undertaken as needed.