Arthritis in Dogs (cont.)

Physical Therapy

Moderate exercise is beneficial because it maintains muscle mass and preserves joint flexibility. Excessive exercise, however, is counterproductive. Arthritic dogs should not be allowed to jump up and down and should never be encouraged to stand up on their back legs. Dogs with pain and lameness should be exercised on a leash or a harness. There are veterinary physical therapists who can help design an exercise (and weight loss) program.

Swimming is an excellent exercise that improves muscle mass without overstressing the joints. Exercise can be increased as the dog improves with the use of medications.

Overweight dogs should be encouraged to lose weight. Being overweight seriously complicates the treatment of osteoarthritis.

Immune-Mediated Arthritis

This is an unusual group of diseases in which antibodies are directed against the dog's own connective tissue, resulting in either an erosive or nonerosive arthritis. In erosive arthritis, cartilage and joint surfaces are destroyed. In nonerosive arthritis, there is inflammation but no tissue destruction.

Rheumatoid arthritis is an erosive arthritis that occurs primarily in toy breeds and other small breeds, such as Shetland Sheepdogs, at approximately 4 years of age. It is characterized by morning stiffness, shifting lameness, and swelling of the smaller joints, particularly the wrists and hocks. Fever, loss of appetite, and lymphadenopathy are accompanying features.

Nonerosive arthritis tends to occur in midsize and large-breed dogs at about 5 to 6 years of age. The cause is unknown. Signs are intermittent fever, loss of appetite, joint swelling, and a lameness that often shifts from limb to limb. A form of nonerosive arthritis occurs with systemic lupus erythematosus.

The diagnosis of immune-mediated arthritis is made by joint X-rays and specific laboratory tests. Synovial fluid analysis helps distinguish immune-mediated arthritis from infectious arthritis and osteoarthritis.

Treatment: Immune-mediated arthritis responds to anti-inflammatory and immunosuppressive drugs, including corticosteroids and chemotherapy agents. Treatment must be continued for eight weeks or longer. Your veterinarian may use several drugs or drug combinations before determining which protocol works best for your dog. Rheumatoid arthritis is less responsive than nonerosive arthritis to drug therapy.

Light to moderate activity is beneficial, but vigorous exercise, which is most likely during periods of remission, can injure the joints and should be restricted. Overweight dogs should be placed on a calorie-restricted diet. In fact, it may be advantageous if the dog is somewhat lean. Discuss this with your veterinarian.