Osteochondrosis: Osteochondritis Dissecans (OCD) of the Knee, Ankle, and Spine in Dogs
In many joints, the surfaces of bones are lined with cartilage to allow the bones to glide smoothly during movement. Sometimes that cartilage is defective, and that’s where osteochondritis dissecans (OCD) comes in. The disease, characterized by a lifting or separation of the cartilage, can affect the knee, ankle, and spine of dogs. It is almost always diagnosed in large and giant breeds less than 1 year of age. Limping in one or both back legs is the first sign of trouble in the case of OCD of the knee, ankle, or spinal versions of the disease. Treatment almost always involves surgery.
OverviewOsteochondrosis is a developmental disease where portions of the cartilage do not mature at the same rate as the surrounding cartilage. As a result, the cartilage can become thickened in these areas and prone to injury. (Refer to osteochondrosis of the shoulder and elbow for more detailed information.) Any type of force, such as one bone hitting another when a dog leaps, can cause these areas of cartilage to crack and lift away from the bone. When this occurs, the condition is referred to as osteochondritis dissecans.
In OCD of the knee, ankle, and spine, small cracks in the cartilage lead to a lifting or separation of the cartilage, often resulting in a partially or fully detached flap of cartilage in the joint, thereby compromising the ultra-smooth, gliding movements we expect from our dogs’ joints.
Pain from the rubbing caused by the presence of this abnormal cartilage is the inevitable result. The joints of the knee and ankle are most commonly affected, though lesions like this have been seen in other joints as well — most notably at the lumbosacral joint in the spine.
Although OCD has been seen in cats and small dogs, it is almost always diagnosed in young large- and giant-breed dogs (4 to 8 months is most typical).
Symptoms and IdentificationLimping in one or both hind limbs is the most common sign. Affected dogs may not always appear terribly painful — though some undeniably are. They may only have trouble upon rising or appear stiff when they walk. A characteristic “slinky” gait has been described for some hind limb OCD dogs.
Diagnosis is best achieved through X-rays, though some dogs may require CT (computed tomography) scans or even surgery (arthroscopy or arthrotomy) for a more accurate diagnosis.
Affected BreedsOsteochondrosis of these joints is seen in a wide variety of dogs, though most often in large- and giant-breed dogs.
- In the ankle or hock (the most commonly affected joint after the shoulder and elbow), Rottweilers and Labrador Retrievers account for more than 70 percent of cases.
- For the knee form, Great Danes, Labrador Retrievers, Golden Retrievers, Newfoundlands, and German Shepherds are the most commonly affected.
- In the lumbosacral version, German Shepherds, Boxers, and Rottweilers are overrepresented, as are males of these breeds (by a four to one margin over females).
TreatmentIf cartilage lesions are recognized early, at 4 to 6 months of age, before cartilage flaps have formed, it’s possible that the lesions may heal with conservative management. In these cases, dogs may do well on pain medications (like NSAIDs), exercise restriction (until the signs completely subside), nutraceuticals (such as glucosamine), and appropriate weight and nutritional management.
Once a cartilage flap has formed, however, it will not heal, and surgery may be necessary to remove the abnormal cartilage. Still, surgery is not always completely curative in these cases. Knee sufferers, in particular, tend to experience more complications than others, especially if the disease is diagnosed later (past 12 months of age).
Surgery happens either through arthroscopy (a small camera and instruments are inserted into the joint through tiny incisions) or a variety of open-joint techniques (arthrotomy) for all affected joints.
PreventionThere are many factors that may lead to osteochondrosis and OCD, including genetics, rapid growth, excessive dietary calcium, and trauma. One way to prevent OCD is through genetic management. In other words, affected dogs should be spayed and neutered so as not to risk passing down the genetic traits that may lead to this condition.
Additionally, owners should understand that slower growth rates might reduce the risk of OCD. That’s one reason many veterinarians recommend lower-calorie diets for large-breed, growing dogs. Eschewing calcium supplements is advisable. Because hard cement or wood walking surfaces may lead to trauma, softer surfaces, such as carpeting, is also a good idea for puppies of susceptible breeds.
Some veterinarians may also recommend nutritional supplements that target the joint (such as glucosamine) to help support normal cartilage and attempt to ward off the development of osteoarthritis.
This article has been reviewed by a Veterinarian.