Penn Hip

[M&Tdoodles]

I was told recently by a vet friend that Penn Hip is going to be making their registry of all of their the dogs Penn Hip tested "PUBLIC"...Good news for breeders trying to find better hips on possible male studs for their lower scoring females.

The vet also said if you breed a higher scoring hip to a lower scoring hip their would be a higher than average percentage of the offspring having better hips .... he had just returned from a week long Pen Hip Conference...he was full of informative facts.
We have a Male F1B Labradoodle that came in the 90th percentile..woo hoo...one of Kelsey & Kozmo's sons...if anyone is looking..PM us...he is in a guardian home...had another also who had higher scores, but unfort. he was fixed...URGGGH

[KingstonTodd]

What is you feeling on which of the two tests, PennHip or OFA, is a better predictor of actually developing HD later in life? Why? I am debating in my head which one to use for Aero. Obviously one answer is do both, but if you were to do only one....

[MaxandMe]

I did both Todd and I PREFER the Pennhip as it can be done as early as 4mos is ONLY DONE ONCE and is by exact measurements
it also will tell you if there is any indication of HD or not ........it's worth the $$$$ for sure.

[KingstonTodd]

Originally Posted by MaxandMe

I did both Todd and I PREFER the Pennhip as it can be done as early as 4mos is ONLY DONE ONCE and is by exact measurements
it also will tell you if there is any indication of HD or not ........it's worth the $$$$ for sure.

I thought PennHip measured laxity which is not the same as HD, correct me if I am wrong. How accurate is measuring the laxity in hips a 4 months compared to x-raying for the presence of HD at 2 years in predicting HD at 5 years old?

It is nice to have a test done and checked off early and I am tempted by that, but you can do OFA prelims after a year or so (which are quite accurate for excellent and good ratings staying above normal on finals).

I am more concerned with which one is the best predictor of future hip health. We dont have any issues here, but if I am going to choose one I would like it to be the best predictor for my puppies future hips.

[Jac]

Todd, you are right, PennHip and OFA test differently...but I don't know that one or the other is the premium for HD identification...some breeders use both.

My only concern in OFA use is that most breeders using OFA get a preliminary test and then go ahead and breed. I don't think that is wise. The purpose of the prelim test is to let you know whether or not to continue to keep the pup in a program...but the OFA must be repeated, for the official score, BEFORE the dog is bred.

Obviously the benefit for PennHip is the early testing without preliminary scores. Still, the early scores have been shown to change (improvements, from the information I have) when the dog is tested both at 4 months and then again at 1 year or older.

It is up to the breeder which one to use, based on the breeder's beliefs and opinions...but organizations, as you know, require one or the other. I think that if one test was definitive or if both tests were necessary, the requirements would reflect that. So, given that it is an "either or" situation, I think that a breeder can be comfortable with either one or the other...or both.

Personally, I have found that OFA-type film testing at an early age is incorrect in most of the subsequent tests (PennHip) that I have conducted...when the one preliminary test was really bad...the PennHip was great...in the two preliminary tests that were excellent, the PennHip was average, 50th percentile.

My PennHip vet, a very experienced vet who had been doing OFA for many years...told me that OFA can be manipulated and that PennHip was the only true measure...so, based on that, I have preferred PennHip...plus the fact that I can test at a year and feel comfortable with the results.

I just read several articles about nutrition because many breeders swear that if you supplement with natural food vitamin C while a dog is pregnant and if you give the pups vit C until they wean, they will not get HD...well, obviously, there are arguments on both sides...but one thing that I found that surprised me was a study about HD and skelatal issues for dogs...and the conclusion is that we OVER- supplement our dogs and THAT causes problems with the skelatal structure.

[MaxandMe]

PennHip is just ONCE that's it.....the vet has to be specially trained to do this thus goes for schooling
the pennhip is accurate and only is done ONCE they XRAYS are not like OFA where 3 vets look at them and do an average rating

the PennHip......if you want i can send you some links todd some have the xrays as well.....they're awesome !
also you can OFA done at same time for another $30 to $50 if you want

[KingstonTodd]

AM, can you post some links below. I am looking for an actual study comparing OFA to Pennhip in terms of which one is the best predictor of HD, something like this:

Vet Radiol Ultrasound. 2000 Nov-Dec;41(6):484-90.

Comparison of two palpation, four radiographic and three ultrasound methods for early detection of mild to moderate canine hip dysplasia.
Adams WM, Dueland RT, Daniels R, Fialkowski JP, Nordheim EV.

Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison 53706, USA.

Hip joint laxity was evaluated in Golden Retriever (n = 60), Labrador Retriever (n = 23), and Labrador/Golden Retriever mix (n = 24) puppies. Ortolani and Bardens maneuvers, four radiographic measurement indices and three dynamic ultrasonographic measurements were used. Each puppy was evaluated twice; at 6.5 to 9 and 43 to 79 weeks of age. These nine methods were compared for accuracy in predicting the development of canine hip dysplasia with or without degenerative joint disease by a median age of 16 months. The Bardens maneuver was a significant predictor of canine hip dysplasia/+/-degenerative joint disease for Golden Retriever puppies, however, it was not a reliable predictor for the other two breeds. Norberg angle measurements taken with femurs in a neutral position with hips distracted (PennHip position) was a significant predictor of degenerative joint disease in two breeds, but not in Golden Retriever puppies. Ultrasound measurement was a reliable predictor of hip canine hip dysplasia/+/-degenerative joint disease for Labrador/Golden Retriever mix puppies, but was not reliable for the other two breeds. Palpation, radiographic, and ultrasonographic methods of evaluating hip joint laxity in puppies at 6.5 to 9 weeks of age were not consistently reliable for all three breeds in predicting hip dysplasia with or without degenerative joint disease at one year of age. A strong association was found between Norberg angle and degenerative joint disease occurrence, as well as between distraction index (PennHip) and degenerative joint disease occurrence when measured at 52 to 79 weeks of age, but not when measured at 6.5 to 9 weeks of age in these breeds. These results emphasize the difficulty of early detection of mild hip dysplasia in the dog.

[KingstonTodd]

The PennHip site has some nice info:

http://www.pennhip.org/resch_sum.html

And the best part is they include scientific references! I am very impressed.

[MaxandMe]

Todd.......i had spent MONTHS of research before making any decisions, talked to breeders in Canada, Australia and a few in US
re: PennHip Vs OFA. why? to see if they preferred ONE TEST over the other. All came back saying they had switched to PENNHIP

as jac mentioned, it cannot be manipulated also as MORE dogs are added to the databases
(another reason for testing) is that as the puppies tested show less HD incidence and tighter hips
down the LINE you can write to PennHIP and your scores may end up changing from the preliminary test

I am HAPPY TO hear they will soon make them public.

Regarding the links.......i have quite a few to go through and i might also email you some
as a few are quite scientific you might understand more fully

and it took me months to find these resources some with radiographs ....finding reports that compare OFA and pennHip are hard
as it's like trying to compare an apple to an orange

[KingstonTodd]

On the subject of HD:

Selection for breed-specific long-bodied phenotypes is associated with increased expression of canine hip dysplasia
Taryn Roberts, a, and Paul D. McGreevya

Abstract
Hip dysplasia (HD) is the most common skeletal disease in purebred dogs. Radiographic schemes developed to reduce prevalence through selective breeding have had limited success, but the role of selecting for morphological characteristics prized in the show-ring and dictated by breed standards has not been fully explored. This study correlated published scores of hip pathology with measurements of body length to height ratio from photographs of Best-of-Breed specimens from 30 breeds (n = 12/breed) to establish whether selection criteria could be compromising welfare by increasing susceptibility to HD.

Relative body length correlated strongly with higher rates of HD by breed data from the Orthopedic Foundation for Animals (Spearman r = 0.727, P < 0.001), the British Veterinary Association (r = 0.701, P < 0.001), and the Australian Veterinary Association (r = 0.577, P < 0.01). By favouring body shapes that are longer than they are tall, judges may be inadvertently selecting for conformational attributes predisposing dogs to HD, suggesting that ambiguity in breed standards and extreme relative body length phenotypes can engender serious welfare consequences and need to be re-evaluated.

Introduction
It has been suggested that, in the interest of preserving features deemed important in the show-ring, the welfare of many breeds is being compromised by increasing their susceptibility to numerous disorders (McGreevy and Nicholas, 1999). By way of musculoskeletal examples, the selection for roached backs in British bulldogs and long trunks in Dachshunds can result in twisted spines and prolapsed intervertebral discs, respectively (McGreevy, 2007). Given the growing awareness of these potentially avoidable threats to the orthopaedic health of certain breeds, it seems appropriate to explore whether the selection for morphology engendered by current breed standards might be playing a role in the emergence of one of the most common heritable diseases in dogs, hip dysplasia (HD) ([Janutta et al., 2006] and [Remedios and Fries, 1995]).

HD has been reported in most large breeds but its prevalence varies widely ([Todhunter et al., 2003a] and [Wang et al., 1999]). Due to malformation of the coxo-femoral joint, HD manifests as laxity and subluxation of the hip, which lead to abnormal focal loading through the articulating surfaces of the joint ([Hays et al., 2007] and [Wood et al., 2000]). Severe HD is often associated with the development of osteoarthritis ([Janutta et al., 2006] and [Todhunter et al., 1999]) and so can cause pain and even loss of hip function (Mateescu et al., 200.

For decades, there have been attempts to reduce the prevalence of the disorder in many major breeds through selective breeding programmes. Wherever there has been a strong shift to breeding only from dogs with minimal signs of HD, the prevalence has decreased (Wood et al., 2000), but the success of HD control programmes is limited by the extent to which breeders give high priority to HD as a criterion for selection.

Since 1982, the British Veterinary Association (BVA) has operated a scheme in conjunction with the UK Kennel Club (KC) in which owners and breeders submit radiographs of dogs older than 1 year (Wood et al., 2000). A hip score is calculated by summing the subjective ordinal scores from nine components that, as a whole, describe the condition of the joint. These nine features are (1) the acetabular fossa, (2) cranial acetabular edge, (3) caudal acetabular edge, (4) cranial effective acetabular rim, (5) dorsal acetabular edge, (6) femoral head and neck exostoses, (7) femoral head recontouring, ( Norberg angle and (9) subluxation. The components are rated from 0 to 6 (ideal–worst), except for the caudal acetabular edge, which is scored from 0 to 5 (Wood et al., 2000).

The resultant total scores for each hip can be anywhere from 0 to 53 and the hip score of the dog is the sum of these two, spanning from 0 to 106 (Wood et al., 2000). A mean score is calculated for all breeds scored under this scheme and breeders are advised to breed only from dogs that exhibit scores well below the breed average (The Kennel Club, 2006). The Australian Veterinary Association (AVA) has run a Canine Hip and Elbow Dysplasia Scheme (CHEDS) in conjunction with the Australian National Kennel Council (ANKC) since January 2000, using the hip evaluation system developed by the BVA.

The USA’s Orthopedic Foundation for Animals (OFA) evaluates the hip conformation of the dog qualitatively based on nine anatomical components, namely (1) craniolateral acetabular rim, (2) cranial acetabular margin, (3) femoral head, (4) fovea capitus, (5) acetabular notch, (6) caudal acetabular rim, (7) dorsal acetabular margin, ( junction of femoral head and neck, and (9) trochanteric fossa, and classifies the hips into one of seven categories: excellent, good, fair, borderline, mild, moderate and severe. Of these, the last three are considered dysplastic (Orthopedic Foundation for Animals, 2007). Breeds are ranked by percentage of dogs scored as dysplastic, from worst hips (rank 1 – Bulldog) to healthiest hips (rank 153 – Italian greyhound) and the rankings for each breed are published on the OFA website.1

A recent study examining the relationship across breeds between hip scores of the numeric BVA system and the hip grades as outlined by the OFA showed a strong correlation between scores (Comhaire and Snaps, 200, indicating that these two systems, while not directly comparable, are producing similar data on breed susceptibilities.

The hip phenotype exhibited by a dog is the combined result of the effects of an unknown number of genetic and non-genetic (so-called ‘environmental’) factors (Reed et al., 2000). Environmental factors, such as rapid growth rate and high food consumption, have been associated with the development of HD (Todhunter et al., 1999), and dogs raised on restricted diets exhibit significantly lower radiographic scores for HD and decreased severity of osteoarthritis compared to dogs fed unrestricted diets (Todhunter et al., 2003b R.J. Todhunter, G. Casella, S.P. Bliss, G. Lust, A.J. Williams, S. Hamilton, N.L. Dykes, A.E. Yeager, R.O. Gilbert, N.I. Burton-Wurster, C.C. Mellersh and G.M. Acland, Power of a Labrador retriever-greyhound pedigree for linkage analysis of hip dysplasia and osteoarthritis, American Journal of Veterinary Research 64 (2003), pp. 418–424. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (25)Todhunter et al., 2003b). In addition, even the effects of individual anatomical variables, such as hip laxity, have been shown to influence differential susceptibility to HD in different breeds (Wood et al., 2000), with environmental factors such as weight and muscle mass influencing the role of this variable (Henricson et al., 1966).

Contemporary dog breeds manifest in a rich variety of morphologies that differ along a broad continuum of height, weight, length and stature, all of which could have the potential to influence loading through the coxo-femoral joint. The hypothesis that the conformational differences dictated by breed standards might be another factor contributing to susceptibility to musculoskeletal diseases such as HD seems logical and is supported by the finding that one morphological feature, the body mass index (BMI)2 of dogs of various breeds (n = 156) is significantly correlated with the incidence of HD. This raises the question of whether increased weight-to-height ratio can lead to increased susceptibility to HD within certain breeds (Comhaire and Snaps, 200.

We hypothesised that one of these factors, the length/height (L/H) ratio, could influence the expression of HD within breeds. Relative body length is indirectly related to BMI, since a longer dog has the potential to carry more weight for its height than a similar breed that is more square in shape. In this study, breed standard morphological descriptions obtained from the American Kennel Club (AKC), the ANKC and the KC were used in conjunction with quantitative length/height ratio measurements obtained from photographs of Best-of-Breed specimens, from a subset of 30 affected breeds, to examine the relationship between breed-specific morphology and HD health per breed.

Discussion
The current study has shown a strong correlation of relative body length with HD pathology prevalence data from three nations and so strongly suggests that the proportions of longer-bodied breeds may be predisposing them to HD. Correlations previously reported between HD statistics from the OFA and BVA database (Comhaire and Snaps, 200 were apparent in the current study, as was correlation with the available subset of AVA hip scores. We emphasise that this study deals only with between-breed variation. A further step will be needed to investigate whether the same relationship exists within dog breeds, as could be achieved by estimating genetic correlations, which would require pedigree data in addition to HD and conformation data.

All prevalence data from voluntary schemes are potentially flawed by self-selection, as owners of a dog with clinical HD are unlikely to submit such a dog for radiographic screening so the resultant population data are likely to represent under-estimates (McGreevy, 2007). That said, we do not feel that this bias would specifically affect the results of the current study as the proposed origins of any bias in the radiographic data would not specifically be related to body length to height ratios

Previous reports of the risk of HD associated with a high BMI (Comhaire and Snaps, 200 were replicated in the current study of 30 breeds. Indeed, this was the physical measure with the highest correlation with hip dysplasia prevalence as published by the OFA, the BVA and the AVA. BMI values reported here should be interpreted with some caution as they were derived from maximal height and weight values and so may represent higher than normal values for certain breeds. Nevertheless the strong correlation with hip dysplasia prevalence statistics across the 30 breeds supports the existence of a relationship between these variables. The relationship between BMI and relative body length is worth considering as related risk factors for hip dysplasia but relative body length may be the more accessible of the two metrics to judge in the show-ring. One would predict that relative body length correlates with BMI because longer-bodied dogs will carry more weight for a given height at the withers. When considering two breeds of comparable build and height, an animal from a breed with an elongated back would likely bear additional weight on its limbs, and perhaps backs over a certain length contribute to the creation of an unsustainable load on the coxo-femoral joint. If this were true, loading through the hip could exacerbate other characteristics of HD pathology such as subluxation, or facilitate the development of osteoarthritis.

Regression estimates from the current study have identified an L/H ratio of 1.06 as the predicted conformation above which percentage excellent values fall below 15%, and 1.09 as the predicted conformation above which percentage dysplastic scores exceed 15%. In addition, breeds in the ‘slightly long’ and ‘long’ categories (L/H ratio above 1.11) showed average percentage dysplastic scores 8.25 times higher than the average percentage dysplastic of more square-bodied groups. While these specific L/H ratio thresholds are only estimates, they further support the notion that backs above a certain length are strongly associated with the pathology of this disorder and bring to light the potential adverse effects of actively selecting for conformations that exceed these thresholds.

While these results suggest that higher L/H ratio may be detrimental in Canis familiaris, its deleterious effects are not predicted by an examination of this proportion in other canine forms (Hildebrand, 1952). Indeed, this conformation is not uncommon in other Canidae but typically arises in species with a lighter frame than seen in domestic dogs of the larger breeds typically affected by HD. Among the Canidae with the longest bodies are the fox species (Hildebrand, 1952), which are relatively light-framed animals, usually weighing less than 10 kg (Whyte Macdonald and Sillero-Zubiri, 2004).

In relation to comparisons with the morphology of wild Canidae, we must bear in mind one critical difference; wild animals are the product of natural selection for adaptive function while the shape of contemporary dog breeds has been selected based almost solely on aesthetics. It has been proposed that in pursuit of breeds distinguished by their morphology, many extreme phenotypes that lack the adaptive fitness of the naturally selected morphology have been favoured, and an increase of the L/H ratio appears to be no exception. So, while breeders of early long-bodied dog breeds may have succeeded in selecting for this particular body shape, there is no guarantee that the anatomy needed to support these morphological changes was, or even can be, selected for simultaneously.

Although previously published correlations of weight and BMI with expression of HD are supported by this current study and suggest that breeds with lower bodyweights and BMI scores appear to be less susceptible to HD, this tendency is not absolute. Eight breeds weighing less than 15 kg fall into the worst 75 breeds ranked for HD by the OFA. Of these eight breeds, five are noticeably longer than they are tall (Norfolk terrier, Shih Tzu, Cardigan Welsh corgi, Pembroke Welsh corgi, Norwich terrier) but because of their hair coat these breeds’ photographs were not measured in the current study. The sixth breed, the Beagle, was measured in this study and had an average L/H ratio of 1.17. The remaining breeds are the Affenpinscher and the Pug, both of which are described as square in shape by breed standards. So, while low BMI and bodyweight may be assisting wild Canidae in supporting a longer frame, the various breeds that show susceptibility to HD despite low bodyweight or BMI scores are evidence that low bodyweight, low BMI or square frame will not necessarily prevent manifestation of this disorder. By the same token, the longest dogs do not necessarily show the highest mean breed hip scores, nor do the heaviest breeds. However, the strong correlations between these measures and HD prevalence across breeds are a powerful indicator that high BMI and high L/H ratio contribute to breed susceptibility to HD and that these metrics may operate in tandem with one another, making the potential vulnerability conferred from high L/H ratio more consequential in heavier breeds, or vice versa. Of the two measures, L/H ratio may be more obvious and therefore assessable in the most important context, the show-ring.

Conclusions
The association between relative body length and HD prevalence described herein calls for drastic revision of breed standards for two reasons. First, many current breed standards allude to the desirability of bodies longer than they are tall (e.g., the Neapolitan mastiff standard stipulates that dogs must be 10–15% longer than they are tall, [American Kennel Club, 2009]) and judges in the show-ring are no doubt actively rewarding the rectangular appearance that is typical of many breeds now plagued by HD, such as the Basset hound and the Dogue de Bordeaux (Orthopedic Foundation for Animals, 2009). Second, across the three countries evaluated in this study, the breed standards’ ambiguity in the specific proportions prescribed, or the total lack of proportional information that characterises many of the breed standards, allow too much room for interpretation on the part of breeders and judges, and promote the repeated selection for conformational extremes. The strong correlation of this morphological variable with disease prevalence, combined with the vast array of other inherited disorders that have been shown to accompany extreme phenotypes in dogs (Asher et al., 2009), indicate that vague descriptors and subjective characteristics put the health and welfare of dogs at risk.

Further research should inform the development of comprehensive breed standards with specific health-oriented morphological guidelines to assist breeders in emphasising the most sustainable and adaptive phenotypes. Humility is an imperative to this process, as peak dog-breeding bodies must embrace the notion that maladaptive morphology that historically have been considered ideal breed characteristics must be abandoned if canine health and welfare are truly to be prioritised.

[KingstonTodd]

FYI: The regestered labrador retriever is "slightly long" with a L/H of 1.19. I actually think doodles would be closer to 1.0, or square, (and thus have less incidence of HD) since the poodle tends to make them a bit taller than if they were a lab, if that makes sense.

[Jac]

Three cheers for long, Poodle legs!

Great article, Todd...I appreciate the research you do and the fact that you share it with us.

I know that before I got into Doodle breeding and before I experienced the variety of dogs out there, I was not even aware of the standard proportions...I have seen many Doodles with short legs and long backs...not a good direction to move into...certainly not healthy for the dogs. But the good breeders that I work with (from this forum and others) are very much aware of the problems that result from that type of breeding...thank goodness the word is beginning to spread.

Sometimes I watch my dogs as they run and it takes my breat away, they are so beautiful and graceful...their bodies are so lean and athletic...the Poodle brings much more than nice coats, in my opinion.

[KingstonTodd]

We got a price quote from the only vet in Kingston that does PennHip.

Hello Todd. Thank you for contacting us. Dr. Xxxxx can do the PennHIP
procedure at 16 weeks of age. The cost is $529.50 plus GST. This
includes the hospitalization, sedation and reversal and the report. Let
us know if you have any other questions, or if you would like to book an
appointment.

EEEEK. But it has to be done.

[Jac]

Goodness Todd! Is that your ONLY PennHip vet?

I have only heard of one that high in California...but they are in San Francisco so they probably get away with it. That is a rediculous amount for the fee...I'd ask for a breakdown of the charges to see what they factor in.

The most I have paid is $380 and that is in the Bay Area...usually it is around $300 but now I have a great vet that does PennHip, elbows, patellas, thyroid, physical exam, and brucellosis for under $300!

[KingstonTodd]

Actually there are two places according to the PennHip locator on thier website. The other is 561$ but that is Hips and elbows. I guess that is just going to be part of the cost of being a good breeder in this area.