Understanding OFA / PH scores

PennHIP Results


Estrela PennHip
Above is an actual PennHip result. This is from our girl Pastorale. As you can see she had poor hips. (she was spayed) This result will tell you many things, for example: how your dog ranks in the test group (breed), your dogs actual reading, and if there is any degenerative joint disease yet. NONE of these should be confused with the other.

Close up

A) Shows the distraction index for the left hip. This is a measurement of the hip joint laxity. This measurement ranges from 0 to 1. Close to zero is tight, close to one is loose. Passy’s left hips is .71. Much closer to 1 than 0. So Passy has loose hips. The next box shows if there is at this time any Degenerative Joint Disease yet. She has none at this time.

B) Repeats for Right hip.

Close up

The blue circle shows DI and DJD numbers concerning your reading.

Passy had a HIGH risk of Degenerative Joint Disease since her distraction index was so high. (.71 and .75)

So, of course, you want this DI number to be LOW.

Notice this line above the green circle. This shows the average for this breed at this time. In the PennHip result below this has average different. As more dogs of a certain breed are tested, the average will change.

Close up

The green circle is what covers where your dog rates against all the other dogs. In Passy’s case, there were 40370 dogs (there were not enough Estrela to rank against so ALL dogs were used) 90% of the dogs had TIGHTER hips than Passy, and 10% had looser hips. So when people give you a percentage number in regards to Pennhip you understand that is NOT that dogs score. Passy is ranked in the 10th percentile….that sort of sounds good doesn’t’ it? But as you can see it is not.

An Estrela PennHip

Now this is a much better score.  This is Juno’s results.  She was tested against other Estrela since now there are enough in there to compare too.  She also is in the 90th percentile.  Meaning her hips are better than 90% of the dogs in the PennHip database.

OFA Results


Estrela OFA Hips


The OFA Hip report above belongs to another of our girls, Fofa.   She was graded a “GOOD”.  OFA is much easier to understand than PennHip.  They give the following passing grades: Excellent, Good, and Fair.  The following grades are failing: Borderline, Mild, Moderate and Severe.

In the case of a Failing grade, your report will look like the one below.  This report belongs to a buhund. She belonged to a friend of mine.  TrailsEnd has permission to use this report.

failing ofa

As you can see from this, Kjersti had Moderate Hip Dysplasia, and you even have the following conditions checked on the right.

An Elbow result will be exactly the same in both cases.  The passing grade is Normal, the failing results are classified as: grade I, grade II or grade III.  With grade three being the worse of the three.


Comparing Databases

OFA and PennHip are mostly used in the USA.  Other countries are now taking advantage of PennHip since you can submit at 16 weeks of age.  However many countries have their own hip grading system.  It is hard to put PennHip on this chart, since they do not have a pass/fail system.  The averages for breeds can change over time with PennHip, which makes grading overall difficult to compare with other databases.

comparision chart

This chart can give you and idea of the equivalent from one database to another.