Elbow dysplasia is an umbrella term used for dogs that have one or more specific diseases of the elbow, all of which result in osteoarthritis. Affected dogs are often young, large-breed dogs who present with pain, inflammation, joint swelling and lameness. The term elbow dysplasia is used to refer to one or a combination of diseases:
- Fragmented Coronoid Process (FCP)
- Osteochondrosis Dissecans (OCD)
- Ununited Anconeal Process (UAP)
- Elbow Incongruity (EI)
This disease causes irreversible damage to the elbow joint and ultimately osteoarthritis. It is important to understand that there is no cure for osteoarthritis and it is always progressive.
Etiology (Why did this happen to my dog?)
Elbow dysplasia is thought to be caused by a combination of genetic factors, overnutrition with rapid growth, trauma and hormonal factors—although the exact mechanism is unknown. Large breeds, including Labrador retrievers, golden retrievers, Rottweilers, Bernese mountain dogs, Newfoundlands and German shepherds are primarily affected. Signs usually begin between 5 to 12 months of age. Pet owners may notice a sudden or gradual onset of front leg lameness and stiffness after a period of rest.
Components of Elbow Dysplasia
Components of elbow dysplasia may be seen in isolation or in combination. FCP is a condition in which a small bone chip has broken off the ulna. This bone chip (black arrow) irritates the lining of the joint and damages healthy cartilage (black arrowhead) of the adjacent humerus. OCD is a condition in which a piece of cartilage becomes detached from the weight-bearing surface of the elbow joint. This results in pain and, with time, arthritis. UAP is a condition in which part of the ulna fails to fuse with itself during normal bone growth. The result is a loose fragment within the joint. Normally, this anconeal process fuses with the rest of the bone by 20 weeks of age. The failure of fusion results in arthritis and pain. EI may also be present in elbow dysplasia. EI is the failure of the joint surfaces within the elbow to fit together well. The poor fit of the humeral condyle, the semilunar notch of the ulna and head of the radius results in pain and arthritis. The surgeons at Spry Companions can help you understand which of these components are present in your dog and what they mean long-term.
Diagnosis
Pain during range of motion of the elbow is the most sensitive indicator for elbow dysplasia. However, many dogs will not show any pain on range of motion and further investigation is still warranted in these dogs. The diagnosis of elbow dysplasia is made through a combination of a careful medical history, physical examination, and imaging techniques. X-rays of the elbows should be taken, and most often, CT scan may be recommended. These imaging techniques are not always definitive. Ultimately, if the surgeon has a high index of suspicion for one or more of these diseases, then diagnostic arthroscopy may be performed through the use of a tiny camera. This allows the surgeon to confirm the diagnosis and concurrently treat any abnormalities.
Treatment
It is important to note that there is no cure for elbow dysplasia. Treatment focuses on minimizing pain and slowing the progression of arthritis in the elbows. Medical management for the secondary osteoarthritis should always be recommended for dogs with elbow dysplasia. Such management would include the use of anti-inflammatory drugs, omega-3 fatty acid supplementation, non-concussive exercise programs and appropriate weight control.
Surgical management of elbow dysplasia completely depends on the abnormalities present and a variety of other factors.FMCP or OCD is usually accomplished through arthroscopy, but management of UAP and EI sometimes requires an open approach. Most commonly, treatment of elbow dysplasia involves arthroscopy. This type of surgery is minimally invasive as tiny cameras and instruments allow the surgeon to address any abnormalities identified at surgery. Following arthroscopic surgery, pets may have moderate swelling around the elbow joints for 1-4 days and may be more lame than before surgery for 1-3 weeks.
Post-Surgical Care and Success Rates
After surgery, 40% of dogs return to normal function, 30-35% of dogs have a only good-fair outcome and the remaining 5-10% showing no improvement after arthroscopic management. Dogs with severely swollen joints and dogs with substantial pre-existing arthritis may not benefit from surgical intervention as much as other dogs. 100% of dogs will have progression of osteoarthritis despite surgical intervention. Post-surgical care includes activity restriction for 6 weeks, continued medical management of arthritis, and following the discharge instructions carefully. A gradual reintroduction to exercise can be performed over the next two months after initial restriction.