Age For Hip Scoring

[Ptolomy]

I have 2 kids that need hip xrays done. One is two this month, the only one is my Norweign boy who is 13 months old. In Norway they x-ray between 12-24 months with the preference being the younger the better. His breeder has suggested getting him done at the same time as my girl.

In the past I have had the hips x-rayed at different ages, 14 months for one but usually around 2 years of age.

So just wondering what age most people x-ray and their reasoning for it.

[Miranda]

I attended a seminar in the U.S. a few years ago and the main speaker was the president of OFFA. Her recommendation was to wait until the dog was at least 18 months, preferably two years. Apparently a dog that scores excellent or good at 12 months will usually score the same at two years, but a dog that scores fair or worse will almost always show further signs of deterioration when x-rayed a year later. So if you want an accurate evaluation of your dog's hips it's better to wait until they're older.

[ish]

What Miranda has said is along the same lines as what I was told by a vet who does a large percentage of the xrays in Vic. He said that the longer you leave it, the more accurate the score because of the additional wear and tear over that time. A dog scored at 12 months hasn't had the wear that a dog of 3 years has, so if at 3 he scores well it is a better indicator of good hips.

Plenty of other factors come into when to score them though. Silly having 2 to do and not doing them together, especially if you have a long trip to the vet etc. My last one was done the week she turned 12 months old, because she had a home waiting for her and it was easier to do it before she left than try to get her back to do down the track.

[Flick_Mac]

I'm pretty sure the PennHIp scheme says it's only accurate from 24months, whereas the other Australian scheme (which I don't think is quite as thorough or regulated) is 12months

[shortstep]

Basically as above with a few different ideas.

Any hip at any age can change and the younger the dog is the more likely it will change, however even at 12 months that risk is not large. It will only change a small amount.

So for example if you get a dog at 12 months with an OFA Excellent to Good range score (total 0-10 AVA) then this dog has almost no chance of developing HD later in life. However if you have a dog that is say Poor to Borderline (AVA 20-25 total) then this dog could have enough change to drop down into the dysplastic range. This dog should be rexrayed at 2 years of age and even again at 4 years if you are breeding this dog.

However, there are good reasons to check hips at 12 months. First off and very important the sooner the breeder knows how the hips are on the last litter, the sooner they can take action. Say a dog has HD at 12 months, well now the breeder knows this and can plan accordingly. If they waited to 24 months or older there is a good chance another litter would have been bred during that last 12 months. So it is not only in the best interest of the breeder but also the buyers to find out ASAP what the hips are doing on any litter of pups.

I would also say that if you find you have hips of some concern the soon you know the better. For example you may want to change your training plans, nutrition or any other number of things for the dog, for example joint supplements can be started sooner. Also if the hips do not look good then postponing desexing a little longer until all growth has finished would be in the best interest of the dog.

So I think screening as young as possible is always the best plan. Then you can make plans for the future and if needed retest the dogs again in a year or 2.

BTW Cornell Uni now has a new method called dorsolateral subluxation (DLS) test to screen with, it is more accurate than OFA and can be done at I think it was 8 months old.

http://bakerinstitute.vet.cornell.edu/contentimages/library/lust-diagnosis.pdf

I am still hoping that one day there will be some interest in this new test down here, as I think it is well worth having in Australia.

Edited June 1, 2011 by shortstep

[Crazy Daisy]

Thanks for the info shortstep.

[Ptolomy]

Thanks for the info and keep the info coming......

Just out of interest - anybody happy to disclose what age they x-rayed for breeding purposes, not because you thought that there was a problem?

[ish]

I've had 2 done at 3 years old, 1 at 2, 3 at 18 months and one at 12 months

[sas]

Min 18 months i.m.o.

[Sayreovi]

Jovi will be getting her's done when she is 12 months. Usually I wait till they are 18 months and I think with Darcy he got done at 2 years, but that vet who said she would have HD at 12 months has thrown me out and I want to know

[Sayly]

Holly was done at about 18 months and Maizie is nearly 20 months old and hers haven't been done yet. I'd personally prefer after 18months.

[Crazy Daisy]

Archer has just turned 12 months so I have been wondering when to have it done. I'm not planning to use him at stud any time soon so I think I might wait another 6 months. 18 months sounds like it's a good age.

[Ptolomy]

I guess what I would like to know is why people want to wait until after 18 months - whats so magical about that age.

Most of the breeders I know wait until close to 2 but when asked why nobody can actually tell me what it is about this age - it just seems to have been passed around the breeders circle as "the age" to get them done.

I guess there is no right and wrong answer to this question - and everybody has their own ideas - but just trying to get it right in my head whether I would be better off waiting to get the boy done (as there is no rush) or whether I have nothing to lose getting him done at 14 months (when I get my other one done).

[shortstep]

I guess what I would like to know is why people want to wait until after 18 months - whats so magical about that age.

Most of the breeders I know wait until close to 2 but when asked why nobody can actually tell me what it is about this age - it just seems to have been passed around the breeders circle as "the age" to get them done.

The reason why people wait is because as the older the dog gets the less likely the hips will change for the worse. If you go to the OFA web site and read the information on their system, it will show the rates of accuracy of scores for every 3 - 6 months of age. the scores will be come more accurate as the dogs gets older.

Here it is http://www.offa.org/hd_prelims.html

The OFA accepts preliminary consultation radiographs on puppies as young as 4 months of age for evaluation of hip conformation. If the dog is found to be dysplastic at an early age, the economic loss from the cost of training, handling, showing and so forth can be minimized and the emotional loss reduced. These preliminary radiographs are read by the OFA veterinary radiologists and are not sent to outside radiologists. The same hip grades are given to preliminary cases.

A recent publication* compared the reliability of the preliminary evaluation hip grade phenotype with the 2 year old evaluation in dogs and there was 100% reliability for a preliminary grade of excellent being normal at 2 years of age (excellent, good, or fair).

There was 97.9% reliability for a preliminary grade of good being normal at 2 years of age, and 76.9% reliability for a preliminary grade of fair being normal at 2 years of age.

Reliability of preliminary evaluations increased as age at the time of preliminary evaluation increased, regardless of whether dogs received a preliminary evaluation of normal hip conformation or HD.

For normal hip conformations, the reliability was 89.6% at 3-6 months, 93.8% at 7-12 months, and 95.2% at 13-18 months.

These results suggest that preliminary evaluations of hip joint status in dogs are generally reliable. However, dogs that receive a preliminary evaluation of fair or mild hip joint conformation should be reevaluated at an older age (24 months).

Now me again, but what they do not say is that it is rare for hips to change greatly after the 12 month mark. So yes, less than 5% of the dogs tested will change their score but they only change a little bit. (also anyone send the same xray around to different scorers, you are very likely to get different scores from each perosn, so it is not an exact number anyway.)

So in most people opinions these days, it is better to look at dog around 12 months. If the dogs has a problem this allows you to start addressing that problem 12 months sooner which can greatly affect the dogs quality of life. This also allows for the concerned breeder to know what is happening with the hips in the litter prior to breeding those parent dogs again, another words if things not looking good they can decide not to repeat thate breeding or not breed those parents at all and prevent breeding more affected pups.

If the dog is poor/ borderline HD or near to the number you would normally stop breeding at, then recheck them at 24 months and see how much they have changed if at all, otherwise retesting is not needed if the dog was well with in the normal range.

BTW I know of more than few dogs that were tested at 12 months and repeated at 24 months and their hips scores imporved, so as said before reading xrays is not an exact science.

Edited June 2, 2011 by shortstep

[Ptolomy]

Thanks Short Step - this info I can relate to.

I have decided to get him done at the same time as I get Cider done and as others have said I can redo him if needs be.

The last girl I had x-rayed I had the x-rays read by 2 different vets +OFA and the results were a total of 21, 17 and the OFA rated as fair.