Hip dysplasia research and PennHip | Dogzine

Hip dysplasia research and PennHip


The OFA has made a list of all dog breeds. On this list is a ranking system to see how many hipdysplasia presents itself in a breed. There are 173 breeds on this list. The French Bulldog is on place 21. This is way too high up! The percentage of French Bulldogs tested positive for hip dysplasia is a whopping 28.9%! That is almost one in three dogs. This is the reason we will evaluate the hips on every dog we intend to breed with. We will make hip x-rays, that will be sended to a special panel from Raad van Beheer. The panel consists of 3 experts.

When the panel evaluates the x-rays the loom at several points. For example the shape of the hip sockets and the femoral head and how well the fit together. They look at the depth of the sockets and the presence of bone deformations alongside the edges of the joints.

All this data together makes a definitive judgement. It can be that only one aspect makes the outcome worse, or it can be multiple factors. You can tell from the information on the certificate.

After judging you will receive the certificate. Different outcomes are possible:

  • HD A (=negative): The dog is based on the x-ray declared clear of HD. This may not mean that the dog is no carrier is the disease.
  • HD B (=transition): On the images there are small changes visible that are the result of hip dysplasia.
  • HD C (=mild positive) or HD D (=positive): The dog clearly shows deformations suiting hip dysplasia.
  • HD E (=positive): The hip joints are severely deformed.

Take into account that HD A does not automatically mean the dog will never suffer from HD. On the contrary, obvious deformations do not automatically mean the dog will suffer from the HD. In this case it would be wise to not overload the hip joints.

Another method is PennHip. PennHip works slightly different than the traditional method bij Raad van Beheer. For a PennHip evaluation the dog does not have to have a pedigree.

On the contrary with the traditional exam with one x-ray, with PennHip 3 x-rays are required. One traditional stretched, one –ray on which the hips are pressed in the sockets and one x-ray where the hips are pulled out of the sockets as far as possible. There is a calculation for how far the hips can come out of the sockets. It is graded between 0 and 1, it is called the distraction-index. Closer to 0 means a tighter hip, closer to 1 means looser. The looser the hip the more chance you get for arthritis.

The x-rays are sent digitally to the specialist on the university of Pennsylvania. All x-rays from across the world are sent there and judged with the same method.

The owner receives a certificate that states the distraction-index from the dog. The average numbers in the specific breed are also mentioned. Very interesting to see how your dog compares to the breed average. Yara her PennHip score is left 0.54 and right 0.63. This is around the breed average of 0.60. They also evaluate other abnormalities on the x-rays, such as arthritis. At this moment Yara has none.

I have chosen for Pennhip next to official hip results because the judging is very different and they look at different things. In official hip results what determines the result is mostly the depth of the hip sockets and bone abnormalities. Pennhip results are an indication of how loose or tight the hips are.

Yara her official hip result from Raad van Beheer is HD A, Norberg value 38, Insufficient joining.