To determine if your own dog or a potential mate is a good candidate to breed, their hips must be X-rayed and graded by an accredited organization to ensure conformation is within acceptable limits to prevent hip dysplasia. Hip dysplasia is a painful, often genetically related condition that, “Develops because of an abnormally developed hip joint, but can also be caused by cartilage damage from a traumatic fracture. With cartilage damage or a hip joint that isn’t formed properly, over time existing cartilage will lose its thickness and elasticity. This breakdown of the cartilage will eventually result in pain with any joint movement.” (OFA) With the loss of cartilage and related elasticity, mobility decreases as well. Essentially bones start to rub against or put pressure on each other because they are no longer firmly in their hip socket and the cartilage which protects the bone and joints deteriorates over time. It is a painful condition for our dogs that only gets worse with time. Hip dysplasia is one of the most common genetically acquired forms of disease in dogs which is also why it’s critical to test for.
There are two recognized methods to analyze a dog’s susceptibility to hip dysplasia. One is, “PennHip,” and can be performed by an accredited Veterinarian who has taken requisite courses to become certified in this process. The other is performed by the Orthopedic Foundation for Animals, commonly known as OFA. Both results are recognized by the American Kennel Club or AKC and can be connected to your dog’s AKC profile. (**For OFA grading it’s important to register your dog with the AKC for hip x-rays to be considered valid due to identification verification purposes). They each grade on different scales using different methods, and opinions about which is a better predictor for hip dysplasia are mixed.
OFA is often referred to as the “Gold Standard” for hip review. The procedure was invented in 1966 and has been widely practiced since. Dogs must be at least two years old to have their results OFA certified.
In this procedure, your regular Veterinarian will take a series of X-rays that are then sent out to the OFA. Those X-rays are graded by three independent radiologists as excellent, good, fair, borderline, mild, moderate or severe; with a final grade resulting from the opinions. To improve the health of the breed, only dogs with excellent or good grades should be considered as parents.
PennHip was invented at the University of Pennsylvania in the late 1980s in an attempt to improve on OFA readings. There have been studies indicating the validity of this claim although their authors often have sometimes had conflicts of interest and existing relationships to the method. PennHip takes x-rays as well but in slightly different positions. It can be performed on puppies as young as 16 weeks of age helping breeders identify dogs to keep in their breeding program. PennHip is scored on a scale of 0-1.0 with any score below 0.3 indicating a low risk to develop hip dysplasia. The rating system on a 100 point scale does allow for more precise comparisons than broader categorical grades in the OFA.
So which do we recommend? Both!
A recent study on the issue found that using both methods was most effective in identifying hip dysplasia risk. Individually each method was effective in predicting hip dysplasia however a significant improvement in accuracy was seen when both methods were used in tandem with each other. Therefore, any breeding prospect should consider being tested by both OFA and PennHip to obtain accurate results. Practically, this can make a difference when selecting a partner to mate with and comparing the various strengths and vulnerabilities of each dog from a breeding perspective.
