Canine Hip Dysplasia - Pathogenesis of Hip Dysplasia in Dogs

Canine hip dysplasia is a common developmentalleads to stretching and tearing of the joint capsule
disease of puppies. It usually affects both hips and isand ligaments in the hip which causes swelling and
seen in many different breeds. It is considered apain. As the dog gets more mature, it is the wearing
multifactorial disease with a strong hereditaryaway of the cartilage and arthritis development within
component but also influenced by environmentalthe joint that leads to pain.
factors.Hip dysplasia in dogs is primarily determined by
The underlying disease in canine hip dysplasia is ahereditary factors. This means that dogs that carry
laxity in the structures that hold the hip jointthe genes for canine hip dysplasia will pass them on
together. A puppy with the disease is born withto their offspring. Even dogs that show no signs of
normal hips. As the puppy develops however, thethe disease may carry the genes for it and if bred to
support ligaments and joint capsule that keep theanother dog that is a carrier, could have offspring
normal joint tight become too loose. This results inwith the disease. This is a large reason why
the femur pulling away from the acetabulum of thecontrolling hip dysplasia in dogs is so difficult.
pelvis, a condition we term subluxation because theRecommendations are to screen both parents and all
joint is starting to luxate but doesn't completelyoffspring in high risk breeds and to not breed any
luxate. This subluxation of the hip joint occurs everydog that shows signs of being a carrier.
time the puppy takes a step.Whether or not a dog shows signs of hip dysplasia is
In a normal hip joint, the head of the femur sitsalso influenced by environmental factors with the
inside the acetabulum and is well covered on the topmain one being nutrition as a puppy. Abundant food
by the dorsal acetabular rim. When a puppy has aconsumption as a puppy has been shown to shorten
dysplastic hip and the joint subluxates, the head ofthe time to first appearance and increase the
the femur puts excessive pressure on the edge ofseverity of hip disease. While overfeeding itself
the dorsal acetabular rim which it is not able todoesn't cause hip dysplasia, it does maximize the trait
handle. This leads to microfracturing of the dorsalexpression in genetically susceptible dogs. The
acetabular rim over time. When the head of themechanism of how this works is not known.
femur subluxates, it also rubs the cartilage off of theRecommendations for high risk puppies are to limit
head of the femur exposing the bone below thefood consumption to 25% less than what is normally
cartilage surface. In puppies, subluxation of the hipfed for the first year of life.