Arthritis in Dogs
Limping and Medicines

Arthritis in dogs is a very complicated process. This article reviews some of the most common causes and treatments for arthritis. Always consult your veterinarian before starting any new treatment or modifying the current treatment for your pet.

Radiographs of a dog with severe arthritis in the hips and knees.

This article will help you understand the most common causes of arthritis in dogs and some of the most popular treatments and remedies. Some remedies can be purchased over the counter; some require a prescription from your veterinarian.

What is arthritis?
A normal joint consists of one or more articular surfaces covered in cartilage, a joint capsule, and joint fluid. Most joints also contain ligaments which provide additional stability. The purpose of a joint is to provide stable weight bearing movement in a non-painful manner. Arthritis is a painful process which will often restrict motion and the ability of a joint to support weight. In a very technical sense, arthritis is any process that causes joint inflammation.

Cross section of cartilage at a cellular level.

What causes arthritis? Arthritis in dogs and cats is caused by many things. We will attempt to look at some of the most common causes of arthritis here.
Hip Dysplasia in Dogs - Hip dysplasia is caused by a very lax or "loose" hip joint. This is usually a condition which occurs during the growth process of fast growing large breed dogs; such as Lab and Golden Retrievers, German Shepherds, and Great Danes. However, any dog or cat can be affected. The hip joint is a ball and socket type joint. The ball portion being the head of the femur (big leg bone) and the socket portion being the acetabulum (cup-like bone off of the pelvis). In hip dysplasia, the socket is too shallow, and doesn't hold the ball portion in place securely. When movement and weight is applied to the joint the ball portion of the joint actually sub-luxates out of place. This chronic sub-luxation creates joint pain and long term arthritis. Typically these dogs will "bunny hop" with their back legs instead of running. They will oftentimes become sore in the hips around 8 months to 18 months of age. Then around 3 to 5 years of age, they will become painful because of arthritis.
Injury - Any type of injury to a joint can cause arthritis. This can include trauma such as being hit by a car, or a ligament rupture such that is seen with a torn or ruptured ACL (Anterior Cruciate Ligament). Any severe damage to a joint even if it is immediately repaired will result in arthritis.
Cartilage Defects in the Joint

A severe OCD lesion with exposed bone and a floating piece of cartilage.

- As bones grow, there is a process in which new cartilage is formed. Sometimes, especially in fast growing large breed dogs, gaps or holes form in the cartilage. This condition is termed Osteochondrosis. It affects the cartilage which covers the bone in a joint. When enough stress is applied to the cartilage over the defect (hole), the cartilage tears off. This creates a divot in the articular cartilage which exposes bone and nerves. The piece of cartilage is left slightly attached or floating in the joint space. When this occurs, it is termed "Osteochondritis Dessicans" or OCD. Usually this condition occurs in the shoulder joint and is frist noticed between 4 and 10 months of age.

What can I do to prevent arthritis?
Sometimes nothing can be done to prevent arthritis in dogs. If you are a breeder, removing affected dogs from the breeding population can help, but is not a gaurantee.
A lot of the bone growth problems seen in large breed dogs are a combination of genetics and nutrition. Making sure that large breed puppies are on a diet specifically for large breed puppies will help. Also, when purchasing a pure breed dog, make sure that both parents are certified by the Orthopedic Foundation of America to have good hips and elbows. Doing both of these will decrease the liklihood hip dysplasia and elbow dysplasia in growing large breed dogs, and therefore reduce the chance of arthritis sooner.
If any lameness is noted on your pet, get it checked as soon as possible. If the lameness is caused by an injury, the sooner it is treated, the less chance arthritis will occur.
Make sure your pet is in the ideal weight range. The heavier they are, the more stress and strain is placed on the joints. The more stress and strain, the increase in chance of developing an injury and arthritis.

What are the treatments for arthritis?
The best treatment for arthritis is actually using a combination of pain control, joint protectants, weight management, and low impact exercise.
Pain Control - The majority of pain control medicines in Veterinary Medicine are NSAIDs (Non-Steroidal Anti-Inflammatories). These drugs are termed non-steroidal because they do not contain a prednisone like compound in them. Prednisone is the most potent anti-inflammatory, but it also has the most severe side effects. NSAIDs are anti-infammatories that still have side effects, some even rarely cause conditions leading to death, but are deemed safer than prednisone type medications. Examples of Veterinary prescribed NSAIDs include: Rimadyl®, Deramaxx®, and Metacam®. You should never use human over the counter or prescription NSAIDs in your dog or cat unless specifically directed by your veterinarian. Some can be fatal to your pet.
Joint Protectants

Glycoflex comes in flavored tablets.

- Joint protectants contain chemicals which the body uses in order to produce joint fluid. Joint fluid is responsible for the nourishment of the cartilage. Without good joint fluid, damaged cartilage has little chance to heal. With good joint fluid, damaged cartilage can heal faster and better. Also, Arthritis in a joint deteriorates the joint fluid. By having a dog or cat with arthritis on a joint protectant, the affected cartilage will have a better chance of healing and they will have a better chance of retarding the arthritic process. There are many joint protectants on the market today. Some are good, some are worthless. There has yet to be a study which is unbiased and looks at multiple products to see which one is the best. I doubt there will ever be such a study because of the number of joint protective products on the market. One product I have used on one of my personal pets (Gracie) and seen great results is Glycoflex®. Gracie had surgery to repair a knee cap luxation when she was 4 years old. She was placed on Glycoflex at that point and continued for the rest of her life. She never developed any noticeable lameness from the injury or surgery and never needed any NSAIDs except for just after surgery. Sadly, Gracie died when she was nine years old from cancer, but there is little doubt that Glycoflex helped her live a pain free life until that point. Glycoflex contains a natural source of glucosamines and is very safe. Since most joint protective medicines contain a source of glucosamine, and glucosamine is a glucose type molecule, they should not be used in diabetic dogs unless specifically prescribed by a veterinarian.
Weight Management - Being overweight or obese can make arthritis unbearable. An ideal weight for any dog or cat is:
1. When you cannot see their individual ribs very well, but they are easy to feel.
2. When looking down on them, there is a waist line after their rib cage.
When looking at them from the side, the bottom of the chest is noticeably lower to the ground than the bottom of the abdomen (stomach).
If your pet is overweight, the easiest way to put your pet on a diet is to:
1. Not give table or people food.
2. Feed 75% of the food you are currently feeding them.
3. Start a light exercise program.
Low Impact Exercise - The best low impact exercise for dogs with arthritis is swimming. Short walks is also good. Just like people, it always wise to start slow and short in time. Gradually increasing distance and time will make it easier to keep an exercise program going. Joints need movement to help them circulate the joint fluid. Arthritic joints that aren't used become stiff and more painful.

This is just an overview of arthritis in dogs and their treatment. Most of the time arthritis need a combination of treatments as described above. If you are interested in purchasing some of the medicines listed above, please visit our online store at www.ACatDog.com.