German Shepherds Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
123 Posts
Discussion Starter #1
Not sure if this is the right place but...

What is the better test, Penn Hip or OFA? Is one better than the other or should you do both tests for the most accurate results?


(seems like this would have already been asked somewhere. If it has, could someone post the link? My search skills are very weak.)
 

·
Registered
Joined
·
1,287 Posts
"Better" is subjective. OFA utilizes a single image and an average of three subjective opinions. The database is much larger and carries more 'clout' with your average person simply because it is wider known. PennHIP is less common but it relies on a series of three images with different pressures being applied to the joint to asses laxity. The dog gets a numerical score which is a literal interpretation. It is non-subjective.

I use OFA because there are not many practitioners in my area certified to take PennHIP x-rays. A dog intended for the upper echelons of breeding (international stud, for example) could be screened in both; one a triple subjective, one an objective numerical assignment.

There's much more to each method, and I'm sure others will fill in the (large) gaps!
 

·
Registered
Joined
·
268 Posts
Penn-Hip, without a doubt. I know some will disagree, but it is the most reliable and accurate analysis. However, nothing is full-proof.

Many dogs who pass OFA won't pass PennHip, so their proponents logically denounce PennHip.

Another advantage of PennHip is that early detection is available. At 16 weeks, three x-rays are taken by a vet certified in taking such images. The distraction index is measured and calculated, based on the breed. If early signs of hip dysplasia are present, then a JPS procedure can be done at the time of neuter or spay to EASILY prevent exacerbation of the disorder. A tiny portion of the anterior pelvis (the symphysis pubis, about 1 cm at the time for GSDs) is cauterized. This allows the rest of the pelvis to grow "out and over" the femoral heads, providing good coverage.

Now, you can surf the internet and find all kinds of armchair opinions, and even some "official" opinions that sound good. But read the veterinary science literature, if you really want to know. I did (but then, I'm a researcher and science professor with a background in radiologic imaging). I also consulted with a GSD orthopedic specialist. But rather than take my word, go to the library and start reading the actual literature in recent peer-reviewed journals. Much better than getting internet opinions, I think. Then you know what you know for certain.
 

·
Registered
Joined
·
1,287 Posts
Myah's Mom, absolutely right! I just attended a talk about the JPS. I'm a fan of the early detection myself and agree that OFA can be very unreliable in terms of actual assessment of laxity.
Moreover, the positioning required for OFA submission is completely unnatural.
 

·
Registered
Joined
·
19,451 Posts
What I do is prelim at 6 months, OFA style positioning or what have you. So far, every dog I've prelimed has looked completely normal. Thus, I've not had a good reason for the added cost of additional films plus finding a vet that can do a PennHIP. Now if I saw something at 6 months that had me concerned, I'd probably consult with a specialist. Getting the dog the right treatment at the right stages would be my priority over whatever position of x-ray might make the dog look the best for certification. So far I've had an expert taking my x-rays (the PennHIP process is actually based on HIS research and he was on the OFA panel) but he is not able to anymore so I'd have to seek out another expert if I had a dog that concerned me.
 

·
Premium Member
Joined
·
3,779 Posts
"Better" is subjective. OFA utilizes a single image and an average of three subjective opinions. The database is much larger and carries more 'clout' with your average person simply because it is wider known. PennHIP is less common but it relies on a series of three images with different pressures being applied to the joint to asses laxity. The dog gets a numerical score which is a literal interpretation. It is non-subjective.

I use OFA because there are not many practitioners in my area certified to take PennHIP x-rays. A dog intended for the upper echelons of breeding (international stud, for example) could be screened in both; one a triple subjective, one an objective numerical assignment.

There's much more to each method, and I'm sure others will fill in the (large) gaps!
To elaborate... PennHIP consists of the OFA position, and 2 others, one of which includes a device to exert pressure on the joint to pull it away from the body. Its meant to capture the hip under strain, and at rest.

PennHIP is without a doubt a more thorough test, and will overtake OFA in time once their database has matured. There are so many cases of 2 OFA films of the same dog on the same day getting different scores, of people with influence protesting and getting a score raised, of OFA good hips showing symptomatic HD, and OFA fair/poor hips showing no symptoms their entire life... I put little faith in OFA personally
 
1 - 6 of 6 Posts
Top