arthritis in dogs - the basics
If you suspect your dog might have arthritis, or have been told that your dog does have arthritis, then a good place to start is by learning more about the disease.
This section of the website contains a wealth of information on what arthritis is, how to identify arthritis in your dog, and what it can mean long-term.
Osteoarthritis (OA) is the most common cause of chronic pain in dogs. It affects 80% of dogs over the age of 8 years old, and potentially up to 35% of dogs of all ages. It is considered a welfare concern in companion animals such as dogs, especially if left untreated.
Arthritis is often considered to be a disease of old age, however unfortunately it can occur in dogs of any age. This is due to the fact that developmental joint disease, which is a disease of younger dogs, is the leading cause of arthritis. Developmental joint disease results in imperfectly fitting joints and subsequent early onset degenerative changes. These changes progress to arthritis, resulting in painful, immobile, and grossly abnormal joints.
By educating pet owners and raising awareness, individuals can learn to identify arthritis symptoms in dogs and take proactive steps to alleviate discomfort and improve their mobility. Furthermore, grooming practices can provide valuable support in managing arthritis by ensuring proper hygiene and comfort for affected joints.
Arthritis simply means “inflammation of the joints”, but in truth the disease is much more complex than this.
Arthritis is commonly and mistakenly described as a disease of the cartilage of a joint. It is in fact a disease that affects all structures within the joint, and if left unmanaged, it can lead to complete joint failure.
Cartilage within the joint is destroyed and not replaced during the degenerative process of arthritis. The inner lining of the joint capsule becomes inflamed, and the outer fibrous layer becomes thickened and restrictive. The normally nutritious, viscous joint fluid thins and loses its viscous support for normal joint motion. New bone is laid down around the joint margins and the bone underlying the cartilage remodels, thus losing its ability to absorb concussional forces. The supportive structures such as ligaments local and distant to the joint weaken, leaving the joint unstable and weak.
Throughout the above degenerative process, the nerve receptors within the bone and joint capsule convey messages of inflammation and tissue damage to the brain. These receptors not only increase in number, but also fire off messages to the brain more easily.
If this process is left unregulated, we will eventually see a process called “wind up” where the brain becomes increasingly aware of the pain signals coming from the joints and magnifies them so what was initially a low level of pain is now perceived as a lot of pain.
other types of arthritis
Arthritis simply means inflammation of the joint, but there are different kinds and should not be confused as each requires a different treatment. A thorough examination by your vet will ensure a correct diagnosis for the best long-term results.
This is the most common form of arthritis, and the eventual outcome of the other types listed here. Also known as degenerative joint disease (DJD), it has many causes such as poorly formed joints (joint incongruity), developmental defects (e.g. osteochondrosis), trauma, instability (e.g. cruciate ligament rupture) and is very prevalent with 1 in 5 dogs suffering from it.
A key factor in its progression is the slow destruction of the articular cartilage of the joint, and other associated degenerative changes in the joint fluid and capsule and underlying bone.
It is often considered to be a disease of old age but in fact can be seen in dogs of all ages. Good management of our young dogs (e.g. care with amounts and types of exercise, good weight control, appropriate home environments) could have a huge impact on the likelihood of dogs developing severe arthritis as they age and we need to be considering how we care for our dogs joints from being a puppy right through to their senior years.
This is commonly confused with osteoarthritis, but is a very different condition. The disease is a very destructive/erosive form of arthritis driven by the body’s immune system affecting major limb joints. The exact cause of the immune system targeting the joints is still not clear. It is generally associated with a fever, a more severe generalised stiffness, and multiple symmetrical joint involvement.
Over time the damage to the joints is so great that they become unstable and grotesquely abnormal to the eye.
This is very similar to rheumatoid arthritis; as the body’s immune system drives the attack on the major joints, the dog will experience a fever and symmetrical joint involvement. However, there may be an underlying cause that if identified and if this is removed the condition may resolve. For example Type 2 immune mediated arthritis is linked with an infection. Type 3 immune mediated arthritis is linked to gastrointestinal disease. Type 4 immune mediated arthritis is linked to cancer. If these conditions are cured then the symptoms of arthritis may also resolve. In the meantime, the condition will require treatment with immunosuppressive drugs, pain relief and lifestyle adaptations. Dogs that develop immune mediated arthritis, even if it is cured, may later develop osteoarthritis as a result of the damage to the joints.
This is a very rare condition similar to immune mediated arthritis described above, however it affects other systems within the dog’s body too, such as the kidneys, the skin, the nerves and brain. It is uncommon but should be considered in a dog showing significant signs of arthritis plus other disease processes.
This form of arthritis is due to an infection, often bacterial, within a joint. It is caused by a penetrating injury, joint surgery or spread from the local area (e.g. the skin). It commonly affects a single large joint and the onset is sudden and severely painful. The joint is generally swollen and hot to the touch. This will lead to severe OA if not identified and treated promptly.
THE JOINT CAN BE CONSIDERED AS AN ‘ORGAN’ WHERE ALL COMPONENTS OF THE JOINT ARE AFFECTED BY THE DISEASE PROCESS.