Osteoarthritis (Degenerative Joint Disease)

The joint cartilage in freely moving joints may degenerate over time, leading to loss of joint movement and, in many cases, pain. This condition is characterized by thinning of cartilage, buildup of fluid within the joint, and the formation of bony outgrowths around the joint. Joint degeneration can be caused by trauma, infection, the body’s own immune system, or malformation during development. This leads to inflammation of the joint membrane, continued cartilage destruction and inflammation, and abnormal joint function.

Signs of osteoarthritis include lameness, joint swelling, wasting away of muscle, and thickening and scarring of the joint membrane. Eventually enough damage can occur that a grating sound might be heard during joint movement. X-rays show increased fluid within the joint, softtissue swelling around the joint, the formation of bony outgrowths, hardening and thickening of bone beneath the cartilage, and sometimes a narrowed joint space.

Treatments can be either medical or surgical. Medical treatment may include the use of nonsteroidal anti-inflammatory drugs to reduce pain and inflammation. However, longterm use of these drugs in dogs can sometimes cause gastrointestinal problems such as lack of appetite, vomiting, and inflammation of the stomach and intestines. Corticosteroids also suppress inflammation, but they are usually given only for a short period in order to avoid adverse effects of continued use. Your veterinarian will prescribe appropriate medication based on your dog’s signs, age, and overall health.

Surgical options include joint fusion, joint replacement, cutting of the joint, and amputation. The outlook for recovery depends on the location and severity of the joint disease.

Other treatments that might be considered include weight reduction, carefully monitored exercise on soft surfaces, and application of warm compresses to affected joints. Joint-fluid modifiers may help prevent further cartilage degradation.

The Merck/Merial Manual for Pet Health. Copyright© 2007 by Merck & Co., Inc.,
Whitehouse Station, NJ, USA. All rights reserved.