Arthritis in Dogs

By: Lorelei Prichard DVM
About the author

Arthritis, also known as degenerative joint disease, is a debilitating condition that is often diagnosed long after the disease has become established. Nearly every geriatric pet will have some evidence of arthritis as the constant movement of joints over a lifetime leads to a “wearing out” of his moveable parts. Arthritis is more common in dogs than cats.

All movement is the result of contraction of muscles across a synovial joint, and a joint is the area where two or more bones meet. Cartilage is tightly bound to the ends of the bones where they interact, and it functions to cushion the ends to facilitate easy, comfortable movement.

When your pet’s joint becomes irritated or injured, damaged tissues release byproducts of the inflammation. These substances further impact the joint as they cause secondary changes to the healthy surrounding tissue. The cartilage that covers the joint surface is avascular (lacking a blood supply) and does not spontaneously heal or regenerate. Therefore, it is desirable to address changes in before irreparable damage occurs.

There are several physical signs of joint disease. Most pets present with a history of intermittent lameness that is more obvious after period of inactivity (sleeping overnight or cage confinement). Lameness may improve after light activity, and strenuous activity often results in more obvious discomfort. The frequency and severity of symptoms increase as the disease progresses.

Pets with arthritis will show limited motion due to pain, swelling, muscle spasms or bony changes. Often, distress may be noticed upon flexion of the affected joint. Symptoms are often accompanied by a decreased range of motion and a compensatory change in the use of the opposite limb.

There are often precipitating factors that lead to joint damage. The most common cause of arthritis is poor conformation and hereditary factors (such as hip dysplasia) which can cause abnormal stresses upon a joint and increase the likelihood of cartilage damage. Exercise-related injury resulting from repetitive long-term trauma or stress on the joints is common in working dogs.

The principles of therapy for arthritis involve addressing and preventing further damage to the articular cartilage. Acute trauma brought on by joint stress can often be reversed or controlled with treatment; however chronic, repeated trauma eventually destroys the protective joint tissues. Loss of articular cartilage (seen in advanced joint disease as in hip dysplasia) may be identified through the use of radiographs.

Prevention is the best way to avoid joint disease, but once inflammation is present in the joint, management is the next best thing. A vicious cycle can transpire as damage caused by inflammation in the joint may lead to cartilage damage that results in yet more injury. The alleviation of symptoms (e.g. pain) and providing comfortable function is the primary goal of therapy.

What can you do to decrease your pet’s discomfort?

Decrease body weight – obese animals should be placed on a reducing diet.
Exercise in moderation – heavy exercise followed by periods of minimal activity can exacerbate the signs of arthritis.
Diagnose joint disease before it becomes a severe problem.
Supplement with chondroprotective agents to stop the cycle of cartilage damage (We recommend Dr. Mike’s Canine Joint Chews). Oral therapy with glucosamine and chondroitin sulfate is often combined with injectable agents (sodium hyaluronate) and/or NSAID’s for better results.

Prior to any therapy designed to address lameness or joint pain, the pet owner should utilize his veterinarian to determine the source of lameness. This can be determined through the use of a physical exam, radiographs, flexion tests, and blood work. A complete exam will enable your veterinarian to assist you in choosing the most effective and beneficial therapy for your pet.

Copyright © 2010 Lorelei Prichard, DVM