Chest Bone Deformity in Dogs

Pectus Excavatum in Dogs

In pectus excavatum, the sternum and costal cartilages are deformed, resulting in a horizontal narrowing of the chest, primarily on the posterior side. The sternum, or chest bone, is a long flat bone located in the center of the thorax, and the costal cartilages are the cartilages that connect the chest bone with the ends of the ribs. In appearance, the middle of the chest appear to be flat or concave, rather than slightly convex.

Brachycephalic (short-nose) breed dogs are predisposed to this condition and in most cases are born with (congenital) this disability.

Symptoms and Types

Causes

There is a genetic predisposition in some dog breeds, particularly brachycephalic breeds, but pectus excavatum can occur spontaneously in any breed. The condition may not be obvious until several weeks after birth unless it is a severe form.

Raising puppies on surfaces causing poor footing may also predispose these animals to developing such a condition.

Diagnosis

You will need to give your veterinarian a thorough history of your dog’s health, any information you have of its parentage and genetic background, and the onset of symptoms. Routine laboratory tests will include complete blood tests, biochemical profiles, and a urinalysis.

Your veterinarian will conduct multiple X-rays of the thoracic cavity to confirm the diagnosis of pectus excavatum. These X-rays will reveal the actual deformities and related structural abnormalities. In some patients, the heart may be shifted from its normal place on the left side of the thoracic cavity due to the abnormal shape of the bones. Abnormalities and concurrent diseases related to the respiratory system will also be visible on X-rays. Echocardiography, a sonographic image of the heart, will be used to further evaluate the heart, its functioning ability, and possible cardiac defects.