Osteochondrosis is a disease that can affect a variety of the joints of a young, growing dog's body. The disease is one of inappropriate bone growth that leads to painful lesions within the joints.
Ultimately, the problem with osteochondrosis is that the bone does not completely ossify (get hard, as bones should), which leads to a thicker layer of cartilage. Thicker cartilage makes for a softer, spongier surface on the ends of the bone. And spongy ends of the bone make for an unstable joint structure. The result of this instability is a defect in the surface of the cartilage within the joint.
With osteochondrosis of the shoulder and elbow, the defects in the cartilage may lead to a variety of disease processes in which a flap of cartilage (osteochondritis dissecans or OCD) or floating pieces of it in the joint (joint mice secondary to OCD) cause painful rubbing. In the end, arthritis (osteoarthritis) is the inevitable result.
Osteochondrosis of the shoulder and elbow occurs primarily in large and giant breed dogs, though smaller breeds may occasionally be affected as well. The rare feline may also be diagnosed with it. The cause is as yet poorly understood, but genetics, rapid growth, high planes of nutrition (protein and fat-rich diets), hard surfaces and excess dietary calcium have all been associated with it.
Pups between the ages of 4 to 12 months are our typical patients, with males overrepresented by a two to one margin. Though one joint is usually more diseased than the other, both sides may be involved in 20% to 80% of shoulder osteochondrosis patients. In the case of the elbow form of osteochondrosis, 20% to 50% of affected dogs have bilateral disease.
Symptoms and Identification
Osteochondrosis-afflicted dogs are typically limping dogs of a young age and larger breed. A lameness in one or both front limbs is typically obvious to the owner, though sometimes a stiff forelimb gait (especially upon rising) is the only sign. Some dogs may even have a so-called, "subclinical" form of the disease in which no signs are present.
X-rays are the best way to get to a diagnosis. But the characteristic defects in the joint's surface may only be visible on certain radiographic angles. So be warned: sedation or anesthesia may be necessary to arrive at a conclusive finding. As the lesions may be subtle, dogs need to be quite still for an effective X-ray in these cases.
In some instances, advanced imaging procedures, such as CT ("cat") scans and bone scans--or even surgery--may be recommended for a more accurate diagnosis.
In all cases, osteoarthritis (arthritis) is the inevitable result, sometimes even if treatment is undertaken early on. As most of these dogs are required to bear significant weight on these joints, even microscopic changes to the cartilage will lead to eventual inflammation (swelling) in the affected joint.
Osteochondrosis of the shoulder and elbow joints is seen in a wide variety of dogs, though most often in large and giant breed dogs.
The following breeds are most commonly diagnosed with the shoulder form:
For elbow disease, the following breeds have been determined to be more at risk:
Bernese Mountain Dog
The most commonly recommended treatment for osteochondrosis's effects involves surgery to remove the unwanted, painful flaps of cartilage that disallow normal gliding of the joint's surfaces against one another. Open-joint surgery or arthroscopy is advisedly undertaken to effect this removal and return the joint's linings to a more normal contour, thus eliminating the source of pain.
Conservative management through pain relief is also possible, though owners should understand that this approach is unlikely to achieve desired results (a consistently pain-free joint with a lower risk of future arthritis). Treatment is largely supportive, consisting of pet-specific pain medications, including NSAIDs (like meloxicam and carprofen) and non-narcotic opiates( like tramadol).
If this disease was picked up on routine X-rays and no limping or pain is evident, then no treatment save nutritional supplements for long-term support of the cartilage (such as glucosamine) is necessary. Such supplements are now considered routine for all affected OC patients, regardless of severity.
The expense all depends on the severity of the disease. For dogs with no pain, the costs are usually limited to supplements, which larger breeds of dogs should arguably receive anyway. (I always recommend them.)
If, however, the disease process leads to lameness, pain relief through drugs is in order. This can be expensive over the long haul ($30-$100 a month) but their benefits are currently considered to be worth the significant expense.
Early surgery is the mainstay of dogs with a noticeable cartilagenous flap within the joint. Without it, the joint will become painfully arthritic within months. And this is no cheap surgical procedure, I assure you. That's because board-certified surgeons, with their wealth of training and experience, are the go-to veterinarians for this procedure. Expect to spend between $2,000 and $4,000 per joint. Arthroscopic procedures tend to lie on the more pricey side due to the cost of the equipment and the additional training these veterinarians bring to bear.
Prevention of OC is primarily achieved 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 may mean a lessened risk. That's why veterinarians now recommend lower-calorie diets for large breed, growing dogs. Eschewing additional calcium supplementation is also advisable, as is the provision of softer surfaces 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 any future arthritis. This is currently considered advisable, with or without surgical intervention.
 Hanna FY. Lumbosacral osteochondrosis: radiological features and surgical management in 34 dogs. J Sm Anim Pract 42: 272, 2001
Johnson AL, et al. Osteochondritis dissecans of the femoral head of a Pekingese JAVMA 187: 623, 1985
 Peterson CJ. Osteochondritis dissecans of the humeral head of a cat. N Z Vet J 32: 115, 1984
 Smith MM, et al. Clinical evaluation of dogs after surgical and nonsurgical management of osteochondritis dissecans of the talus. JAVMA 187: 31, 1985
 van Bree H. Evaluation of the prognostic value of positive-contrast shoulder arthrography for bilateral osteochondrosis lesions in dogs. Am J Vet Res 51: 1121, 1990