Diagnosis

When a dog is being evaluated for arthritis, the veterinarian will go over the canine patient's medical history and conduct a physical examination. The practitioner will want to know about your pet's lifestyle as well as the symptoms and behaviors you have observed at home. During the physical exam, the veterinary doctor will identify and evaluate clinical signs and also palpate the dog's joints. In the early stages of arthritis, only soft tissues are affected and, thus, the disease may very well not be evident on an x-ray. However, the dog's joints will be swollen and sore, and the veterinarian will be able to detect this through the physical examination.

If the arthritis has progressed far enough that bone changes have begun to occur, x-rays can be very helpful with identifying the arthritis and assessing the degree of joint damage. Other diagnostic methods may also be employed in order to identify the specific form of arthritis present and to evaluate the stage and progression of the disease. For example, blood tests and joint fluid analysis can be used to diagnose certain types of arthritis. When infectious or septic arthritis is affecting a dog, the fluid surrounding the joints (synovial fluid) will contain white blood cells and bacteria. With a case of rheumatoid arthritis, blood tests will indicate that the dog's system is attacking its own joints. Furthermore, a number of other tests, including an antinuclear antibody test, can be used to confirm a diagnosis of rheumatoid arthritis in a canine patient.

Causes

Different forms of dog arthritis can be caused by different factors and conditions. Osteoarthritis is a form of degenerative joint disease that results from cartilage destruction. This damage to the cartilage can occur for several reasons. Sometimes, abnormal joints are at the root of the problem. For example, hip dysplasia is a condition involving the malformation of hip joints. When a dog suffers from hip dysplasia, its hip joints are unable to withstand normal amounts of stress, leading to damage and arthritis. Traumatic injuries, constant jumping, or strenuous exercise can also cause degenerative joint disease, by placing abnormal stress on the dog's joints. Therefore, normal levels of stress can lead to arthritis when joints are abnormal, and abnormal levels of stress can lead to arthritis when a dog's joints are normal.

Since degenerative joint disease can result from wear and tear and increased stress on the joints, there are certain factors that can contribute to a dog's likelihood of developing osteoarthritis. For example, larger dogs tend to be more prone to developing osteoarthritis, probably due to the increased weight and stress placed on the joints. For similar reasons, overweight dogs are at a higher risk for developing this condition. Senior dogs, working dogs, and those with certain conditions like diabetes also tend to be more likely to end up with osteoarthritis. Inflammatory forms of joint disease include septic arthritis and rheumatoid arthritis. These types of arthritis are much less common in dogs than osteoarthritis, especially rheumatoid arthritis, but they can occur. Septic arthritis can be caused by an infection, including bacterial infections, fungal infections, and tick-borne diseases. Rheumatoid arthritis, on the other hand, is caused by an underlying immune-mediated disease. This involves a weakness in the dog's immune system that causes the animal's body to attack its own joints. Often this underlying condition will be hereditary.