Is Legg-Calve-Perthes in Canines the Same as Hip Dysplasia?

Legg-Calve-Perthes is a disorder that is sometimes mistaken for hip dysplasia. It was discovered in 1910 by Drs. Legg, Calve and Perthes, who observed a flattening of the tops of children’s femurs. Examples of canines with the disorder were first documented in the 1930s. Although the two conditions are different, the same X-ray images can be used to detect the presence of hip dysplasia or Legg-Calve-Perthes disease.

Legg-Calve-Perthes is a disease that has no known cause and can occur in one hip joint or in both, without any precipitating trauma. The disease affects small, young dogs and seems to be strongly determined by genetics, occurring in equal numbers of female and male canines. In dogs with this disease, the blood supply is obstructed before it reaches the upper part of the femur -- the femoral head or "ball" part of the joint. The lack of blood flow leads to disintegration and breakage of the bone and cartilage. The affected hip joint and surrounding area become inflamed and irritated, which is painful for dogs suffering from Legg-Calve-Perthes.

Hip dysplasia is not the same as Legg-Calve-Perthes disease, although both conditions affect the hip joints of some dogs and both seem to have a genetic origin. Hip dysplasia is a common disorder that causes afflicted dogs a great deal of pain because of abnormal hip movement, inflammation, damaged and irregularly shaped bones and cartilage, tiny bone fractures and, at its worst, joint deterioration. Young dogs with hip dysplasia have anatomical abnormalities that result in an improper fit between the ball of the femur and the pelvic socket. The ball of the joint is too loose to move properly in the pelvic bone’s concave socket, which is too shallow, which results in a partial dislocation of the joint itself. Genetics, nutrition and environmental factors all may contribute to the likelihood that a dog will suffer from hip dysplasia.

Miniature or toy breed puppies and small terriers who are between 5 and 8 months old are most commonly afflicted with Legg-Calve-Perthes disorder. Yorkshire terriers, miniature and toy poodles, West Highland white terriers and miniature pinschers are a few of the breeds predisposed to being diagnosed with the disorder, according to an epidemiological study conducted by Elizabeth LaFond, DVM, and published in the Journal of the American Animal Hospital Association in September 1, 2002. The study was designed to determine which dog breeds are at risk for a variety of developmental orthopedic diseases. The study also looked at the prevalence of canine hip dysplasia and determined that the breeds most likely to develop this orthopedic disease are German shepherd dogs, Labrador retrievers, golden retrievers and rottweilers.

Because both Legg-Calve-Perthes and hip dysplasia have genetic origins, avoid breeding dogs who have been diagnosed with either condition or puppies whose lineage includes dogs with these disorders. This is the most reliable way to prevent dogs from producing litters with puppies who eventually could suffer from these likely inherited disorders. Whether you plan to purchase a puppy from a reliable breeder or decide to adopt a purebred puppy or dog from a rescue organization, request all the information available about your new family member. Ask about your pup’s behavior, health, lineage, as well as results of her canine family's medical evaluations, including tests performed to discover or rule out genetic conditions common to her breed or size.