Osteochondritis dissecans (OCD) in Dogs

No, OCD isn't a condition that compels your dog to keep checking on his buried bones or constantly wash his paws. In this case, OCD stands for osteochondritis dissecans, a painful joint disease that affects shoulders, elbows, and knees.

OCD mainly strikes large-breed dogs, and is fairly common in Golden Retrievers, German Shepherds, Rottweilers, Great Danes, Bernese Mountain Dogs, and Saint Bernards. Not all big breeds are vulnerable: OCD is less likely to affect Doberman Pinschers, Collies, and Siberian Huskies.

Most often the cause is rapid bone development, so OCD is usually found in puppies between four and eight months old. However, it can occasionally be found in older dogs, as well as smaller breeds. It affects male dogs about five times more often than females.

The pain is caused by inflammation and lesions on the smooth cartilage in the dog's joints, right where the bones meet. Small pieces of the cartilage break off and float free in the joint. Those bits of cartilage don't die; they keep growing. (In fact, they even have a painfully cute name: "joint mice.") Once they're floating free, fluid builds up and calcification occurs. The joint gets inflamed and swollen, nerves get irritated, and the pup is in pain.

Causes

No one's quite sure what causes OCD. Heredity is obviously part of the problem (and if you can, you should ask if your dog's mother or father had the condition). Too much stress on a young dog's bones, restricted blood flow to the cartilage, diet and nutrition, and weight problems may also be factors, but exactly how much or how preventable the condition might be isn't known.

When it's time to see a vet

It's fairly easy to notice if your dog has OCD. First, be aware if your dog is one of the large breeds prone to the condition. If so, watch for any of these signs :

• Limping
• Favoring one paw or leg while walking or even when lying down
• Swelling at the shoulder or, more rarely, the elbows and knees
• Pain when trying to extend a swollen joint

A vet can make a solid diagnosis with an exam and some X-rays.

Treatments

There are two kinds of treatment for OCD: conservative and surgical.

Conservative treatment is used for mild cases and the youngest dogs. It's basically four to ten weeks of very restrictive "bed rest," where walking is restricted to bathroom trips. That means no running, no romping. As difficult as that can be to enforce, the cartilage will then heal on its own in about 60 percent of cases, and the dog can get back to playing.

Surgery is used for more severe cases, or where the conservative approach hasn't worked. In the surgery, the vet will remove the joint mice and repair the lesions. After surgery and a couple of weeks of rest, almost all dogs make a complete recovery and return to 100 percent function. It's very rare for the condition to recur.

Prevention

Prevention is an iffy proposition. Some people believe that an overweight growing dog will be more likely to develop OCD, but there isn't much evidence yet.

Still, it's common sense to protect a young pup's limbs from unnecessary physical impact, such as repeated jumps off a deck or out of a car. And diet certainly plays a role; there are a number of puppy foods that promote healthy bone growth and may reduce your dog's odds of getting OCD.