More About Osteoarthritis (OA)

Arthritis - a word that means inflammation of a joint—occurs in both people and dogs. Chances are you know someone with arthritis, as it affects about one in every six adults. Of those, almost half suffer from the pain and disability of osteoarthritis. While more than 100 forms of arthritis are known to affect people, OA and rheumatoid arthritis are the types seen most often.
 

Understanding what osteoarthritis (OA) is goes a long way in helping you know how to make your dog feel like a pup again.
 

Figure 1: Cycle of pain
 

Like the OA that affects people, osteoarthritis in dogs (canine osteoarthritis) is an inflammation in one or more joints that affects approximately one of every five adult dogs*. That’s nearly 600,000 dogs in Canada alone! Joints such as hips, elbows and knees are especially prone to osteoarthritis.
 

If OA isn’t detected and controlled, a vicious cycle of pain and disability occurs. Damage to cartilage—a rubbery, slippery tissue that covers the ends of bones in joints—triggers inflammation as the tissue tries to repair itself. This inflammation causes pain, which can lead to a decrease in exercise and, in turn, to a loss in muscle tone and strength. Less exercise combined with muscle loss can lead to weight problems or obesity, which can increase stress on the damaged joint and more cartilage breakdown.
 

Joint cartilage breakdown, inflammation and pain are often present before obvious signs of a problem are noticed. Since OA cannot be cured, it’s very important to spot the subtle signs of OA pain in your dog as early as possible. Your dog’s veterinarian can do a routine screening for signs of OA pain, so be sure to ask for one. If osteoarthritis is identified, you and your veterinarian can take steps to control pain and inflammation, increase your dog’s ability to move and improve your dog’s quality of life.
 

Figure 2: Anatomy of a joint

Osteoarthritis (OA) is caused by abnormal stresses on a normal joint or instability of the bones forming the joint due to trauma or abnormal anatomy.
 

A joint is a connection where two bones meet. Ligaments and a joint capsule hold the bones together as shown in Figure 2.
 

When the joint gets damaged by trauma or an altered force due to improper alignment of the joint, there is physical damage to the cells that make up the joint. This physical damage causes an interruption of healthy cell production within the joint. Note the physical differences between a healthy hip joint and a non-healthy hip joint as shown in Figure 3.
 

Figure 3: Arthritic vs. healthy canine hip joint.
 

The surface of the cartilage gets worn down, the joint capsule swells with inflammation and the tissues around the joint become painful.
 

*Data on file