WHAT IS ARTHRITIS?
The term arthritis is the medical term for inflammation for one or more joints. The main symptoms of arthritis are painful joints and stiff movement. There are several different types of arthritis that dogs can suffer from including immune mediated poly-arthritis, septic arthritis and the most common form osteoarthritis.
Immune Mediated Poly-Arthritis (IMPA) is caused by the dog’s own immune system attacking its joints (similar to how humans are affected by rheumatoid arthritis). The term ‘poly’ means ‘many’ and this unfortunately means that IMPA affects multiple joints.
Septic arthritis (also known as infectious arthritis) is a type of joint inflammation caused as a result of contamination by a microorganism getting into the joint from the environment. Commonly this infectious agent is bacteria often from a wound leading directly into the joint, but occasionally can be viral or fungal in origin.
Osteoarthritis is the most common type of arthritis affecting dogs. This degenerative condition causes a breakdown of the protective cartilage around the joint causing pain and stiffness. Osteoarthritis occurs due to old age or from a previous injury or trauma, and this is the type of arthritis we will be discussing in this article.
Read on to find out more about the symptoms of arthritis in dogs, how arthritis can be managed to make our canine companions more comfortable, and why losing weight and changing your dog’s exercise regime can be beneficial for pets with joint disease.
ANATOMY OF THE CANINE JOINT
Before talking about osteoarthritis, we must first understand the normal anatomy of a joint. A joint occurs at the point where two bones come together. The bones are held together by strong tissues such as ligaments. There are three different types of joints in the body; fibrous (immovable joints in the skull), cartilaginous (which allow some movement e.g. in the spine) and synovial (movable joints such as the hip, elbow and shoulder). The synovial joints are the most common and these are the ones most prone to arthritic changes because they allow for movement and are therefore prone to wear and tear.
Overweight dogs are at a much higher risk of developing osteoarthritis and are 2-3 times more likely to suffer from ruptured cruciate ligaments than dogs that are at their ideal weight.
In a synovial joint the ends of the bones that meet are covered with a smooth cartilage. This cartilage allows the ends of the bones to glide over each other. Cartilage also acts as a shock absorber for the joints when your dog is running and jumping. The gap around where the bones meet contains a thick fluid called synovial fluid, and this fluid is secreted from synovial membranes. The fluid helps to lubricate the joint to allow it to move smoothly. Strong tissues called ligaments hold the bones together and tendons connect bone to muscle.
WHAT IS OSTEOARTHRITIS?
The form of most arthritis seen in our companion animals is osteoarthritis, also known as degenerative joint disease. This type of arthritis involves destruction of the cartilage that allows joints to move smoothly and pain free. This leaves the bone exposed, which is painful. To understand this more, imagine feeling your bones grating together every time you bend your knee.
WHICH DOGS ARE AFFECTED BY ARTHRITIS?
It’s estimated that 20% of middle aged to geriatric dogs have osteoarthritis. Arthritis can develop due to a number of reasons, such as an old injury or diseases such as cruciate ligament rupture or developmental diseases such as hip dysplasia. Animals that are overweight or have excessive exercise (especially repetitive exercise like running for a ball over and over again) can increase the wear and tear of joints and make arthritis worse.
OVERWEIGHT DOGS ARE MORE LIKELY TO SUFFER FROM ARTHRITIS
Overweight dogs are at a much higher risk of developing osteoarthritis and are 2-3 times more likely to suffer from ruptured cruciate ligaments than dogs that are at their ideal weight. Being overweight can put extra strain on the joints increasing their pain. Furthermore, new research suggests that adipose fat tissue actually produces chemicals (adipokines) which can increase inflammation. However, it’s never too late to help your dog lose weight, even after they’ve developed joint problems. Losing weight has been shown to reduce lameness in dogs with joint disease making them more comfortable and mobile. If you’re unsure if your dog needs to lose weight, consult your local vet surgery and check out this body condition chart.
SIGNS OF OSTEOARTHRITIS IN DOGS
Signs include: stiffness (especially first thing after getting up), limping, licking at the painful joint (you may see saliva staining), difficulty getting up or down stairs or into the car, abnormal posture (a hunch in the back), abnormal gait, circling several times before lying down (trying to get comfortable), slowing down, reluctance to go for a walk and irritability or aggression due to pain, especially when being touched or picked up.
VETERINARY TREATMENT OF OSTEOARTHRITIS IN DOGS
Although osteoarthritis cannot be cured, there are a number of treatment options available - many of which you can try at home, such as joint supplements. Furthermore, often one of the single most important things you can do for your arthritic pet is to help them lose weight or maintain a lean healthy weight. Later on, as the disease progresses, your vet can provide pain relief and anti-inflammatories and they may also recommend your dog has some type of complementary therapy such as hydrotherapy. You can read more about the different active ingredients in joint supplements here and about the different treatment options for dogs with osteoarthritis in our next article on the treatment and management of this condition.