What is it?
Arthritis (or “osteoarthritis”) is a joint disease associated with pain and inflammation. It usually happens through the normal wear and tear of movement, resulting in damage to the cartilage inside the joint. Cartilage smooths joint movement and damaged cartilage means that joint surfaces become roughened and inflamed.
Septic arthritis is less common. This is associated with joint infection from a wound or an infection in the body affecting the joints. Rheumatoid arthritis (caused by the immune system) is rare in rabbits.
Why is it important?Rabbits are exceptionally good at hiding discomfort. They have many predators in the wild so it would be high risk to show pain or weakness. However, arthritis can be very painful and it is important to identify and manage symptoms to make them comfortable.
What’s the risk?
Most rabbits over 6 years old will have a degree of arthritis. It is most common in the hip, elbow and stifle (knee) joints. Abnormalities in joint and bone formation or damage to these structures can result in younger rabbits developing arthritis.
Giant rabbits are more likely to develop arthritis. Obesity also increases the risk of arthritis and speeds the progression of the disease.
How do you know what is going on?
Uncomfortable rabbits may hide, eat less and slow down considerably. They may avoid areas of the hutch that include steps, ramps or obstacles. If they find it difficult to enter the litter tray, they may toilet inappropriately or miss the tray. You may notice sores on the hocks from sitting for long periods or marks on the front of the hindlegs where they are constantly knocked as they cannot clear steps.
Rabbits with arthritis are often lame or stiff when getting up. They may wobble and look weak as they are reluctant to stand on an affected leg. Cold, damp weather can exacerbate the stiffness.
Joints may appear swollen and feel warm. The rabbit may be reluctant to be handled and their behaviour can change because of pain and fear, they can become aggressive.
Grooming can be difficult for rabbits with arthritis so their coats can become dirty and matted. They may find it too painful so reach their bottom to eat their caecotrophs so these soft faeces will be seen on their coat or around the hutch. Positioning themselves to urinate can be very painful so you may see urine scalding on the skin around their genitals. Bladder emptying may be incomplete encouraging the formation of bladder stones.
What can be done?
As rabbits can slow down and hide with many health problems, a veterinary examination will determine if arthritis is causing their symptoms. The vet will check the range of joint movement. This is reduced by arthritis. Swelling, pain and inflammation can also signify arthritis.
If septic arthritis is suspected then a sample of joint fluid may be taken to determine the bacteria involved. This will be treated with antibiotics specifically as well as managing the arthritic change.
Blood tests may be required if rheumatoid arthritis is suspected.
If osteoarthritis caused by wear and tear is most likely, an x-ray, CT scan or MRI scan may be considered to investigate further. This condition is managed by environmental changes, diet and pain management:
Remove any obstacles, steps or ramps that the rabbit finds hard to negotiate. Ramps can often be lengthened to make them less steep.
Surfaces should be smooth but non-slip. A shallow layer in bedding can be used to absorb urine but prevent bedding tangling around feet and impeding movement.
Gentle exercise should be encouraged but too much exercise can exacerbate discomfort. If your rabbit has an energetic companion, areas where they can get away and rest are ideal.
Weight control is an essential part of arthritis management. Heavier rabbits are more severely affected so maintain a healthy body weight with a healthy diet. Rabbits should eat 80% grass or hay, 5% pelleted rabbit food and the remaining 15% made up of vegetables and some treats.
Commercial food producers provide senior foods which contain glucosamine and other joint supplements. There is little research into the effectiveness of these supplements. However, many owners see a long term improvement in mobility on an appropriate diet.
If the pain of arthritis is managed well the rabbit will move around more and the joints become less stiff. Non-steroidal anti-inflammatory drugs are usually used (NSAIDS), to reduce inflammation in the joint, therefore reducing pain. As they can affect the liver and kidneys, blood tests may be necessary before and during their use. Unfortunately, there are no drugs licensed for long term use in rabbits in the UK but your vet will advise you on safety and monitoring.
Physiotherapy and acupuncture can also help with pain management in arthritis. Your vet can advise you on access to these treatments.
What can I do to protect my pet?
Careful observation of your rabbit’s behaviour and mobility can alert you to any change in their wellbeing. Check them daily for any sores, matts or a dirty bottom. Clip fur around the bottom if it helps to keep them clean and check the area. Check their body weight, weigh your rabbit regularly as subtle changes can result in unnoticed weight gain or loss.
Arrange a regular veterinary check. Treat any infections promptly to prevent the joints becoming infected causing septic arthritis.
Use a layer of soft absorbable bedding on an enclosure with a solid floor. Keep your rabbit warm, away from draughts and leaks. Encourage regular exercise in a safe environment.
Arthritis is a common condition, early intervention and management can improve an arthritic rabbit’s quality of life considerably.