Elbow Dysplasia

What is Elbow Dysplasia?

Elbow dysplasia is a multifaceted disease that can affect both juvenile and mature dogs. The complex of elbow dysplasia can be divided into the following categories:

–        Fragmented coronoid process (FCP)

–        Medial compartment disease (MCD)

–        Osteocondrosis dissecans (OCD)

–        Ununited anconeal process (UAP)

–        Elbow incongruency (EI)

–        Ununited medial humeral epicondyle

One or more of these problems can be affecting your pet and can cause a varying amount of lameness. We generally believe that elbow dysplasia is a congenital issue and affects mostly larger breed dogs, but can affect small breed dogs, as well.

Diagram of the canine elbow.

Diagram of the canine elbow.

The “ins” and “outs” of Elbow Dysplasia

Clinical signs: The most common clinical sign that is reported in dogs is front leg lameness. This can vary in intensity and can come on slowly or acutely (all of a sudden). Some pets will develop swelling at the elbow. Typically, limping becomes worse with activity and can subside with rest. Unfortunately, clinical signs can vary from pet to pet.

Diagnosis:  A thorough exam is recommended to isolate the elbow as the problem. It is important to evaluate the whole front leg as well as the opposite leg for any abnormalities. Because elbow dysplasia is congenital, both elbows tend to be affected (>80%).

Radiographs – In juvenile dogs, changes can be very minimal. Classic radiographic signs include: osteoarthritis (anconeal ridge is an early sign), sclerosis            (thickening) of the ulna, joint swelling and fragmentation of the medial coronoid process (33-50% visible on x-rays). OCD and UAP lesions typically will be evident on x-rays. It is standard to take three views of each elbow.

Patient with elbow dysplasia. Note the osteoarthritis present.

Patient with elbow dysplasia. Note the osteoarthritis present.

Patient with an ununited coronoid process.

Patient with an ununited coronoid process.

CT scan – Computed tomography (CT scan) may be necessary in some cases to make a diagnosis. A CT scan is a different type of x-ray and requires that your pet be anesthetized. The advantage of a CT scan is that it gives us a greater detailed image of the joint allowing us to detect mild changes. Sensitivity of a CT scan is >90% in diagnosing elbow dysplasia.

3-D image reconstruction of an elbow CT scan.

3-D image reconstruction of an elbow CT scan.

Treatment: Successful treatment of elbow dysplasia can occur with early diagnosis and treatment. The more advanced the arthritic changes (which will occur with time), the less successful treatment becomes. The following is a brief overview of the current treatments that are performed, usually in combination. 

Arthroscopy – Considered to be the “gold standard”, arthroscopy allows us to obtain critical information about the joint by looking in the joint via a minimally invasive approach. A scope and camera are introduced into the joint and the joint surfaces are assessed for arthritis, cartilage wear, incongruency and fragments. If fragments exist, these can be removed with arthroscopy. If substantial cartilage wear is present other procedures may be recommended.

Conservative management – this includes non-steroidal anti-inflammatories drugs (NSAIDs), supplements, physical therapy, acupuncture, and regenerative stem cell therapy. Unless your pet is very severely affected this therapy is often used in conjunction with arthroscopy and surgical management.

Advanced surgical procedures – Depending on the assessment of the joint, other procedures may be recommended such as the following: sliding humeral osteotomy (SHO) or unicompartment elbow replacement (CUE) for medial compartment disease, biceps tendon release and elbow replacement surgeries.

Patient with a Sliding Humeral Osteotomy (SHO).

Patient with a Sliding Humeral Osteotomy (SHO).

“Will my dog get better?

Prognosis – With early diagnosis and aggressive treatment, the success rate of the treating elbow dysplasia is ~80%. This generally entails elbow arthroscopy and sometimes more advanced procedures. Also, if changes are detected on the opposite leg, arthroscopy of this leg is recommended as well. In about 20% of the cases we need to combine multiple treatments and sometimes arthritis and discomfort will still progress.

Elbow replacement surgeries are still up and coming and can be considered in pets with “end-stage” changes to the elbow.