Elbow dysplasia in dogs

Overview

Elbow dysplasia refers to several elbow diseases that result from developmental abnormalities in the elbow joint of growing dogs. The elbow joint is composed of three bones (humerus, radius, and ulna), which should grow to fit together properly. The humerus is the long bone in the foreleg above the elbow.The radius extends from the elbow to the wrist and is the main weight bearing bone of the foreleg. The ulna is parallel to the radius and acts as a lever arm for the extensor muscles in the elbow joint.

During the first 24 weeks of your dog's growth, there are two small bones which start as cartilage and gradually turn to bone as they fuse with the ulna:  the medial coronoid process and the anconeal process. Two of the most common conditions of elbow dysplasia occur if these bones fail to unite, as in ununited anconeal process (UAP), or even break off from the ulna, as in fragmented medial coronoid process (FCP). The third most common condition of elbow dysplasia, Osteochondritis dissecans (OCD), is diagnosed when a fragment of cartilage within the joint fails to attach to the bone. Such fragments in the elbow joint are abrasive, causing severe irritation, and lead to arthritic changes.

Many large breed dogs are affected and elbow dysplasia is more common in males than females. UAP and FCP are most commonly diagnosed in dogs between six months to 12 months but can be hard to definitively diagnose because of poor visibility with normal x-ray techniques.

Symptoms

• Lameness and/or pain in the forelegs:  usually intermittent and most common seen in dogs at 4 to 10 months of age, becoming gradually more apparent, and may become more pronounced after exercise.
• Abnormal gait:  often characterized by excessive flipping of the front feet.
• Bowed elbow:  particularly when moving, but severely affected dogs may show bowed elbow(s) when standing
• Swollen joints
• Pain on manipulation of the joints

Prevention

Because elbow dysplasia is a genetic condition, it cannot be prevented, but factors such as growth rate, diet, level of exercise, and trauma can influence the severity of the symptoms. If your dog is of a breed predisposed to elbow dysplasia, consult your veterinarian about the proper quantity and energy content of food to prevent rapid growth rate. Chondroprotective products, such as cosequin and glucosamine, are products that provide essential ingredients needed to repair cartilage as well as help prevent inflammation that causes pain and swelling. When exercising your dog, minimize those activities that create high impact on developing joints, such as jumping down, particularly onto hard surfaces.

Treatment

Surgery to remove bone or cartilage fragments is the usual treatment. If unequal bone growth is the problem, surgery may help to relieve the pressure at the joint. Medical therapy is usually a combination of weight control, appropriate exercise, chondroprotective products, and anti-inflammatory medications.
Surgery and medical therapy can relieve pain and improve mobility, but because elbow dysplasia is a progressive disease, degenerative joint disease (arthritis) is always a probability.

Arthroscopic surgery is minimally invasive, and most dogs recover quickly, often walking within a day or two. Activity should be restricted to short walks on leash for the first 6 to 8 weeks, and then gradually increased as allowed by your veterinarian.

Sources:

Barnard, Charles, Canine Elbow Dysplasia. (10 February 2008).

Carlson, Lisa D, D.V.M., and Giffin, James M., MD. Dog Owner's Home Veterinary Handbook. New York:  Howell Book House, 2000.

De Boer, Henry, Dr. Henry De Boer Jr. on Elbow Dysplasia. Working Dogs. (10 February 2008).

Vezzoni, A., Early Diagnosis and Treatment of Canine Elbow Dysplasia. 11-Jan-2006.