Hip Dysplasia: Is it genetic or environmental?

BradA1878 · July 2009

What do you guys think, is Hip Dysplasia genetically or environmentally caused?

I would like to hear all your thoughts, and if you have any references to back up your thoughts (like links to published studies) I would love to read them.

I would love to see a documented case of HD being caused by an environment, just for curiosity and educational purposes.

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tsukitsune · July 2009

Good question. I have no idea, but when I first heard that someone had indicated HD was environmental (or nutrition) related rather than genetic, I was really taken back by it. It just doesn't seem logical. If environmental factors are to blame, they MUST be in conjunction with or an exaggeration of HD caused by genetics.

Quick Google search brings this page:
http://www.bordercollie.org/hd.html#n8
in which they site this:
Studies of several breeds in Europe*, where hips are required to be graded, indicate the problem is approximately 70% hereditary and 30% environmental. Hereditary traits include breadth and slope of the pelvis, angulation of the hip joint, ligamentation, and muscle mass. Dogs with a slightly sloped, broad pelvis, normal angulation, tight ligamentation, and good muscle mass seem to have the best hips. Dogs bred to have exaggerated angulation in the hindquarters, extreme pelvic slope, or are poorly muscled, poorly angulated, and narrow in the hips seem more predisposed.(7) Environmental factors seem to be overnutrition and physically overstressing the joints with early training and pIaying. Supplementation with calcium has also been implicated.(8)

*Interesting, right?

For reference (8) this is sited:
Daniel C. Richardson DVM, Vet Clin: Sm Anim Pract Vol. 22, no. 3, pp. 529-540.

Perhaps he would be someone you should try to contact?
This may or may not be him: http://search.k-state.edu/?qt=richardson

I'm going to pose this question to our canine nutritionist, I'll let you know what she says.

Ryu · July 2009

When Roxy was diagnosed, our vet indicated that it is a genetic disease - that she was born with the condition and it worsens over time. To be honest, I didn't do much research into the cause of the HD - just how to fix it.

WrylyBrindle · July 2009

my understanding is that is genetic- shallow sockets- and that you can exacerbate it, but only if it is there to be exacerbated to begin with. I have never read that a dog with normal hip ball/socket function will displace under normal dog life wear and tear. I mean you can tear a muscle or get hit by a car, or work them too hard as pups, but that's not dysplasia.

I have requested this topic be covered in the Tufts lecture series, but it wont happen until next summer.

BradA1878 · July 2009

Thanx for the info!

The 70/30 thing is interesting, I wonder how they got that #. I watched the video below and seems like it would take a lot of blunt trauma to actually cause HD w/o the dog being genetically predisposed to it.

Video:

I'd also love to know the definition of "early" in "physically overstressing the joints with early training and playing " as well as a quantification of "overstressing".

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StaticNfuzz · July 2009

Like mentioned above I really think it is a combination of things physically, genetically, environmental and nutrition.

I thought it was interesting he noted it is rarely seen in greyhounds. I imagine that it probably was culled out (whether selectively or naturally) since the dogs in the past were used to course and not necessarily overly pampered. Based on that foundation it may be less prevalent now in the breed as a whole. Also as a breed they tend to lounge around more when they are not coursing. I have seen few bank off couches, perches and rock formations etc. like the Shibas do.

Just my take
Snf

ShikokuSpirit · July 2009

I believe that it is mostly genetic. The only other way I could see it being "environmental" is if it was from a physical injury from either extreme stress or (critical)damage. Or maybe forced to shape and develop that way through interventation...ya know...like some of those human tribes (i.e. the cone heads, enlongated earlobes, etc). I could see some nutrition possibly being an issue, I'd imagine this would effect the entire bone structure thoughout and not just limited to hips.

BradA1878 · July 2009

The greyhound thing has always interested me, sight hounds in general have almost perfect hip across the board. It always made me wonder why some breeds don't out-cross to sighthounds just to improve the hips - especially in a working breed that is valued more for workability than confirmation (like the CC, or the Anatolian).

I mean one out-crossing could potential "fix" a hip issue in a breed and would hardly be noticed after a generation or 2.

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AkiraleShiba · July 2009

That's a great question, I think that some people love to stress the environmental facts because it serves them but at the same time dogs have never had more comfortable living situations! Just think before the advent of commercial dog food what people would give to their dog, not an equilibrated diet it probably consisted mostly of cereals and other cheap stuff. Also, people did not carry their dogs in the stairs until quite recently still, I do not think that hip dysplasia was more recurrent then.

I think that bad health, and therefore bad hips, is systemic, too much preventive medicine and vaccines, selection based on looks, unadapted diet so we are producing weaker and weaker dogs except for some working lines. But I think the biggest problem is that the gene pool is getting restricted so bad genes are not diluted enough and are rather getting more common.

tsukitsune · July 2009

"But I think the biggest problem is that the gene pool is getting restricted so bad genes are not diluted enough and are rather getting more common."

I think that, when speaking about nihon ken specifically, is the major factor. Gene pool = genetics. Hip testing is so vital, patella testing too, to produce pups with a sound structure and therefore sound vitality for life. When a breeder does not take that into account and relies solely on the premise of their lines' history without testing themselves, the results (whether right away or a few generations later) are going to be disastrous. Chrystal used a great word for what the above mentioned pups' environmental factors can do - exacerbate their already compromised health systems.

JiroGo · July 2009

I have heard of a dog getting HD due to being severly beaten in quarantine, but I would imagine that is a pretty rare case.

Leonberger · July 2009

I do not believe a dog can get HD from environmental causes, if it wasn't already present. I understand it as being a genetic issue, that can be enhanced due to environmental issues. A healthy hip can, of course, be dislocated or stressed to a point where the cartilages wear too much and becoming arthritic. I don't see any of these as HD.
Without wanting to be too literal, dysplasia comes from a Greek root that's loosely translated to malformation. Malformation is not misuse.

BradA1878 · July 2009

Without wanting to be too literal, dysplasia comes from a Greek root that's loosely translated to malformation. Malformation is not misuse.
>> Great point, and I agree with your other statements. For example, Kaia, she doesn't have HD but just had her hip dislocated... does that mean she will now have HD - no, as HD is a disease and Kaia has an injury, not a disease.

I have heard of a dog getting HD due to being severly beaten in quarantine, but I would imagine that is a pretty rare case.
>> Wow, that's REALLY sad!

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Sangmort · July 2009

I'm with Rui 100%. I've seen Hip Dysplasia only show up in 1. Bad breeding practices 2. Pet store / puppy mill puppies 3. Breeds where the genepool is extremely limitied.

I've known dogs from good breeders who were fed, what we consider to be, crap food after they went home to their new families & never develop Hip Dysplacia. I have also seen pet store / bad breeding / puppy mill puppies go home to famillies who feed them the best of the best kibble; Orijen, Acana, etc. & supplements & STILL develop Hip Dysplasia. [ look at Pam's poor babe Roxy... ]

So I deffinitely think it's genetic, not malnutrition or environmental. I believe OTHER issues can arise from environment / trauma / malnutrition, but not Hip Dysplasia...

My $oo.o2 ~

lindsayt · July 2009

Brad, I do believe greyhounds and other ancient sighthounds are behind several well known breeds and have been used to develop structure in more recent breeds. Their lite builds, poor dentition/poor dental health and greatly increased risks of bone cancers would have to be considered, especially if planning to cross this with a working breed, who must have a full healthy mouth to do the job and also be structurally sound.

I personally would consider progressive arthritis to the point of destroying the hip socket and blunt traumas that also result in a ruined hip socket (like an untreated dislocated hip from a hit by car) to be a type of dysplastic hip, just as much as a genetic hip dysplasia that would be seen in a young animal. That's my thinking, and I may be incorrect.

Leonberger · July 2009

I agree that some trauma, like Lindsay said, can evolve to a dysplastic-like scenario.
Lamarck defended that acquired traits could be passed on to the next generation and, as we know, he was wrong, so if a dog with an original healthy hip, that has one of these traumas, breeds; his progeny will come out healthy while a dysplastic dog will probably have dysplastic progeny.

What I think environment can do is increase the gravity of an existing HD. Meaning a B level can evolve to full blown D or E (FCI ratings) from inadequate exercise at early ages, but I don't believe an A1 hip (OFA E / PennHip under4) can get as bad from the same inadequate exercise.

ShikokuSpirit · July 2009

My friend pointed out a really excellent observation. That people shouldn't be so concerned about "rating" so much as to the "shape" of the socket. I mean...a dog can still rate "good" but I believe there are a few "levels" within each rating. So in actuality this "good" could be closer to an "excellent" or even a "fair". I believe the issue is more OFA-related in particular. I haven't looked too much into but, from what I hear there are breeders who prefer the Grade system...as it seems to be more accurrate when it comes to hip evaluation.

So paying extra special attention to those sockets should provide you with more information then the actual rating. For example, a dog could "pass" with a breedable rating and yet have nearly dysplastic hips.

TeamLaika · July 2009

Hip dysplasia is hip joint laxity resulting in osteoarthritis. Not the other way around. If the hip joint is tight and well conformed, you won't get subluxation, shallow acetabulums, thickened femoral necks, and flattened femoral heads.

It is polygenic and multifactorial. That's why a few generations of sprinkling in sighthounds won't clean it up in some breeds. It's also why you can have pups with bum hips born to HD 'clear' dams and sires.

It is also a developmental disease. The DEVELOPMENT of hip dysplasia is influenced by environment. A dog may display extreme joint laxity at 4-6 months, but not have any osteoarthritis or pain until he is a year old or older.

This 'developmental' aspect is the problem with OFA and other grading systems that are based on the standard hip-extended x-ray view. A dog may be graded OFA 'good' or 'fair' at age 2, yet be anything but 'good' at age 11. OFA results should ideally be paired over time. (Except noone ever does. Instead championships are routinely awarded to immature dogs, and then it's off to the breeding shed as soon as those tests are done at age 24 months) If the dog has been dealt a poor hand genetically and has hip laxity, the environmental influences he experiences will only affect the RATE of the development of clinical signs and osteoarthritis. He will develop it regardless, but that's where physically stressing could exacerbate matters. Furthermore, individual dogs also vary in their response to their condition. (Some are incredibly stoic.)

There is a direct relationship between hip laxity and the radiographic evidence of osteoarthritis.

I feel that PennHip is a superior test. OFA scores when the dog is aged 5 years or older would be better (more accurate) than OFA scores at age 2.

A truely healthy hip is not going to be stressed or arthritic at any age. LaikaTrio's sire was a hunting dog from Estonia. He didn't have a cushy life -lived outside the majority of the time and spent hours on the trail of wild boar. I have no idea what he ate. He was awarded OFA 'excellent' hips at AGE ELEVEN when he was imported to the US.

BradA1878 · July 2009

wow, Sarah, OFA perfect at 11 years old is amazing! I guess that shows a perfect hip, is a perfect hip.

Thanx for the info!

So a dog that shows "severe HD" before the age of 12 months would have to have been predisposed (genetically) to HD, correct? In other words, could environmental factors (on their own) cause "severe HD" in a dog under 12 months (or any age, for that matter)?

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Sangmort · July 2009

IMHO, No.

[ hmm....how about a poll on this Brad? Might be interesting. ] ~

tsukitsune · July 2009

It takes more than opinion though, like Sarah said - "It is polygenic and multifactorial... It's also why you can have pups with bum hips born to HD 'clear' dams and sires."

Any dog with severe HD would have had to be genetically predisposed (in any past generation) regardless of any exacerbating environmental factors including diet, hypothetically. Also, hypothetically, the parents of that 12 month old pup were obviously not tested, test too soon, or misread as clear.

BradA1878 · July 2009

Right, because even if OFA at 2 years showed all-clear the dog's radiographic may not show osteoarthritis until much later (like 5 years). Correct?

StaticNfuzz · July 2009

Thanks Sarah for the input...

Yeah, it makes sense that there is probably an underlying weakness in the structure to begin with. Although I do think certain environmental factors and nutrition probably pushes it past the norm in becoming a problem which is probably pronounced much sooner. Much like the straw that broke the camels back, how much environmental/nutritional stress will push the limbs beyond its threshold before expected natural life span of the dog ends. That varies with each animal.

As Sarah mentions, it is true many folks do not continue with evaluation throughout a dog's life. If you look in OFA, after the 24 month initial screening a great majority do not pursue screening and testing over a life time. There are many dogs that develop late onset symptoms and that really needs to be looked into from beginning to end.

I would think there would be a bell curve in regard to screening that establishes the degree of luxation for knees or degree in laxity for hips in relation to average age of onset. It would be interesting to see something that identifies when/where the breakdown might occur in a particular related group of animals.

Snf

tsukitsune · July 2009

Thats what TeamLaika said, I think she's as expert opinion as you can get on here!

If the dog is born with tight, well formed hip joint (genetic!) then you will not have dyplastic symptoms or issues - thats how in understand the structure/genetic portion of the puzzle. If this is the building block, then a dog showing these issues so very early on never had a chance due to his genetics.

Can you "poll" specialty vets? I think they could build a good case on the subject.

tsukitsune · July 2009

My only understand, ever, of HD came from this:

"Hip dysplasia is an inherited disease of the hip in which the ball and socket joint that it comprises is malformed. This malformation means that the ball portion (the head of the femur) and its socket (called the acetabulum) don’t properly meet one another. The result is a joint that rubs and grinds instead of sliding smoothly.

As the biggest joint in the body, the hip bears the bulk of a dog’s body weight during basic activities like rising from a lying position and climbing or jumping. So when it isn’t shaped just right, a lifetime of rubbing and grinding results in…even more rubbing and grinding."

Inherited. Exacerbated. From a blog written by a practicing DVM in Miami, FL.

http://www.dolittler.com/2008/10/19/dog.cat.veterinary.veterinarian.hip dysplasia.surgery.Rimadyl.Metacam.html

http://www.dolittler.com/2008/10/27/dog.veterinary.hip dysplasia.veterinarian.cost.X-rays.diagnosis.OFA.PennHip.html

http://www.dolittler.com/2009/06/22/Hip-dysplasia-part-3-The-real-cost-of-treatment.html

http://www.dolittler.com/2006/07/20/pet.vet.dog.vs101.7.20.06.html

WrylyBrindle · July 2009

Do the straighter back legs of many asian dogs impact their hip/knee disposition? chows and sharpeis have very straight legs, nihons are very upright dogs, too. They dont stand like a GSD or a pointer or a hound, all curvaceous and coiled.

Maybe that's a bad example- GSD s are so notorious for poor hips I overheard one of Jeff's old man soccer group teammates going on about how sore he was after a game- "Me and my german shepherd hips..."

Sangmort · July 2009

Hmmm. I think the problem with GSDs lies in the fact that Breeders really want that "Angeled" back / hips. I know a GSD breeder who bred working dogs explicitly told me they do NOT breed for "angles" as it produces poor hips. [ no idea how accurate this is, just what I heard from a Working GSD breeder as oppposed to a GSD breeder who breeds for conformation ] ~

ShikokuSpirit · July 2009

Ah...the Deutscher Schaeferhund (GSD)...

...they're really great dogs but there's way too much variety in the breed now.

Standard does call for some angulation so that they could do their job more effectively (original purpose of creation)

I honestly, I don't see what the need was to create a problem...when there wasn't one to begin with -sighs-. Yeah...I'm not a fan of "fads".

Sangmort · July 2009

Actually, that's what the Working GSD Breeder's dogs looked like Corina. He's been trying very hard to breed out that angulation, as he said, because it causes problems with the hips for no real reason.

He had some amazing dogs. The angulation wasnt QUITE like the pictures yo posted, but I can see him getting there after a few more generations of breeding. ~

lindsayt · July 2009

Corina, I really admired the breeding in some of the earlier Schaeferhunds, they actually look like they can do the job they were bred for.

I haven't done Ike's hips yet. Honestly, he won't really finish maturing physically/filling out until he's about 3.5 anyway, so I don't see a good reason to get a rating right now while his body is still changing, especially as he isn't being used at stud.

ShikokuSpirit · July 2009

I have prelims done on Lynx and will do another x-ray probably next year (*I missed the special discount clinic this year and Shoushuu will be ready for next year). She got a "good" rating from OFA on hips, but they looked pretty close. Since she was still maturing, my belief is that they only got better with age. Reguardless of the rating, you can tell that the formation is still correct. If I can somehow access that disc they gave me (on my laptop) with her x-rays, I could post up a copy.

Though sometimes people may see it as "unnecessary" (if you have multiple dogs, yes it's costly) I think it nice to x-ray a "before" and "after". If they were good hips, you want to see that there isn't any negative change. If they are not so good, you can only hope that they will get better or at least not get any worse.

Hip Dysplasia: Is it genetic or environmental?

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