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Achy Breaky Bones

By Liz Alton, DVM

At 11 years of age, Angus, a black lab, looked like an old dog: his black fur had turned almost white on his face and muzzle. But his aging was most noticeable in the way he walked into my veterinary hospital for his annual physical. As I watched Angus' stiff, stilted gait I suspected that he may be suffering from degenerative joint disease, or arthritis.

Arthritis is a catchall term for many diseases including achy, stiff joints. Because weight seems to be a factor in its development, virtually every dog over 60 pounds will eventually develop some degree of the disease. Cats and very small dogs are generally spared. Degenerative joint disease (DJD) refers to a specific condition where the cartilage, the cushioning cap of the bones making up a joint, cracks and chips away over the years exposing the underlying bone. This results in bone-on-bone contact and inflammation, causing pain and discomfort. DJD usually begins in dogs after the age of eight.

Although DJD can develop in any joint, it seems to affect the hips, knees, and lower spine most often. As the cartilage slowly disintegrates, pain and inflammation begin. Soon, the joint is large and swollen. With acute flare-ups, the dog can develop a severe limp or be unable to get up at all.

DJD has no cure, but there are things that concerned owners can do to help their arthritic companions have a more comfortable life:

• Prevent your dog from becoming too fat. Each extra pound of weight applies multiple pounds of pressure on a single joint. All overweight arthritic dogs should be on low fat food.
• Arthritic dogs should remain active. As DJD develops, joints become less flexible. Soon, the simple act of bending a joint becomes excruciatingly painful. Because swimming involves no weight bearing by the joints, it is much less traumatic to the joints than other forms of exercise. Swimming keeps the joints flexible while increasing metabolism to help maintain a lean body mass.
• Food supplements that seem to have therapeutic effects called nutraceuticals are available to help our arthritic pets. Glucosamine, chondroitin sulfate, and MSM (methlysulfonyl methane) are three of these products. Water is essential for healthy cartilage, as it both lubricates and nourishes the cartilage. Without water, the cartilage loses its cushioning effect, and becomes more susceptible to cracks and chips and eventually wears away. Glucosamine supplements help to build and restore these water loving molecules while chondroitin sulfate supplements act as "water magnets," allowing each small molecule to hold many more times water. The result is a cartilage that retains its soft, flexible nature, and resists wear and tear. Glucosamine and chondroitin sulfate can be administered by mouth in the form of capsules or pills. MSM is a naturally occurring sulfur compound that is found in every cell of the body. Its functions include helping the synthesis of collagen, maintenance of membrane flexibility, and promotion of cell regeneration. In conjunction with glucosamine and chondroitin sulfate, MSM appears to help keep cartilage healthy and decrease the inflammatory process.
• Ibuprofen and Tylenol, commonly used arthritis medications for humans, should never be used in dogs or cats. They are extremely toxic to our pets and may result in death.
• Arthritis is a progressive condition. Your veterinarian may eventually prescribe stronger medication such as a nonsteroidal anti-inflammatory drug. Although there are unwanted side effects to most all the drugs in this class, there is some good news. Over the last few years, new inflammatory medications have been developed. These new drugs help reduce inflammation and cartilage destruction without some of the serious side effects of older medications.
• After a summer of swimming, losing ten pounds, and supplementation with nutraceuticals, Angus appeared about four years younger. He was once again able to climb the stairs to sleep on the floor of his owner's bedroom. And, although he would never again be able to jump the backyard fence or chase the neighbor's cat far, he was much more comfortable, healthier, and took his daily walks with greater ease.

Dr. Liz Alton is a member of the Vermont Veterinary Medical Medical Association.