Specifically, the PennHIP method considers a DI of less than .3 to be the threshold below which there is a near zero risk to develop hip osteoarthritis later in life. In contrast, dogs having hip laxity with DI higher than .3 show increasing risk to develop hip osteoarthritis, earlier and more severely, as the DI increases.
Comparing the overall results of the study, 52 percent of OFA-rated "excellent," 82 percent of OFA-rated "good" and 94 percent of OFA-rated "fair" hips all fell above the PennHIP threshold of .3, making them all susceptible to the osteoarthritis of CHD though scored as "normal" by the OFA. Of the dogs the OFA scored as "dysplastic," all had hip laxity above the PennHIP threshold of .3, meaning there was agreement between the two methods on dogs showing CHD or the susceptibility to CHD.
The key feature of the PennHIP radiographic method is its ability to determine which dogs may be susceptible to osteoarthritis later in life. Because dogs are recognized as excellent models for hip osteoarthritis in humans, the authors are interested in the prospect of applying this technology to humans. Knowing a dog's risk for osteoarthritis early would allow veterinarians to prescribe proven preventive strategies, like weight loss, to lower the risk of this genetic disorder. Also, dog breeders now have a more informative measure to determine breeding quality to lower the risk of hip osteoarthritis in future generations of dogs.
"In humans, with appropriate studies of course, it is conceivable that mothers of susceptible children - and there are many - may adjust a child's lifestyle, including diet, to delay the onset or lessen the severity of this genetic condition," Smith said.
PennHIP is currently in common use by service-dog organizations such as the U.S. Air Force, the U.S. Army and numerous dog-guide schools. There are approximately 2,000 trained and certified members currently performing PennHIP procedure worldwide.
Source: University of Pennsylvania