Abnormal Development of the Elbow in Dogs

Elbow Dysplasia in Dogs

Elbow dysplasia is a condition caused by the abnormal growth of cells, tissue, or bone. The condition is characterized by a series of four developmental abnormalities that lead to malformation and degeneration of the elbow joint. It is the most common cause of elbow pain and lameness, and one of the most common causes of forelimb lameness in large and giant-breed dogs. Labrador retrievers, Rottweilers, Golden retrievers, German shepherd dogs, Bernese mountain dogs, chow chows, bearded collies, and Newfoundland breeds are the most commonly affected. The age for onset of clinical signs is typically four to ten months, with diagnosis generally being made around 4 to 18 months.

One type of the condition is more likely to affect males than females: when the bone fragment is located at the inner surface of the upper ulna. The ulna is one of the bones of the foreleg, just below the elbow joint. Otherwise, there are no known gender differences.

Symptoms and Types

• Not all affected dogs will show signs when young
• Sudden (acute) episode of elbow lameness due to advanced degenerative joint disease in a mature patient are common
• Intermittent or persistent forelimb lameness that is aggravated by exercise; progresses from stiffness, and noticed only after the dog has been resting
• Pain when extending or flexing the elbow
• Tendency for dogs to hold the affected limb away from the body
• Fluid build-up in the joint
• Grating of bone and joint with movement may be detected with advanced degenerative joint disease
• Diminished range of motion

Causes

The causes are genetic, developmental, and nutritional.

Diagnosis

Your veterinarian will want to rule out several possible causes for the symptoms before arriving at a diagnosis. For example, whether there has been trauma to the joint, or whether there is an infection that has brought on, an arthritic condition will need to be explored. A tumor may account for the symptoms, and this possibility will be taken into account as well, with x-ray images taken of the affected area for closer examination. Both elbows will probably need to be x-rayed, since there is a high incidence of disease occurring in both legs. Your doctor may also want to order a computed tomography (CT) scan, or magnetic resonance image (MRI) to look for fragments. A sample of fluid will be taken from the joint with a fine needle aspirate for laboratory testing, and an arthroscopic examination (by use of a tubelike instrument for examining and treating the inside of the joint) may be utilized to help for making a definitive diagnosis.