Would you know if your Sheltie had hip dysplasia?
What would you look for and how would you treat it?
As frequently as the phrase is bantered about, there are still a lot of people that don’t have a comprehensive grasp of what it is, how dogs get it and what to do about it. So let’s explore this topic further….
The first cause is genetics. It has been the thorn in the sides of breeders for decades now. Because there never seemed a simple inheritable pattern from parents to pups, it was felt to be polygenetic in nature.
This means not one but several genes may play a role in whether a dog develops dysplasia.
So trying to do selective breeding around multiple genes acting independently was about as easy as nailing jello to a wall.
In May 2014 I found an article stating a breakthrough has been made in the search for the genetic basis for hip dysplasia in dogs. A specific gene has been found in the German Shepherd Dog. YAAA HOO!
So finally there may be some objective means to determine which dogs to breed. It will take time to isolate the gene in other breeds but at least there is some progress.
We think that the genes cause the hip to develop in a less than functional manner in a variety of ways such as:
For example, a hip that has greater laxity in its ligaments (stretching ability) means that the ball and joint don’t sit snugly together when in motion.
For a visual example, make a fist with one of your hands and cover that fist with your other. That is what the hip looks like. Now imagine if you could pull the covering hand off the fist by an inch or two.
That would give the two pieces the chance to bounce around and wear away bone in the wrong places.
Wearing down bone causes pain and bone spurs and eventually hip dysplasia in dogs.
Another issue is how deep does the ball of the femur (the “fist” of the hip bone) sit in the socket (the hand that covers the fist). Even if it is a snug fit, a shallow socket can let the ball of the joint slosh around easier, and again wear away the socket in places it shouldn’t like the edges.
This allows more and more movement in the wrong directions and again total wearing away of the joint.
A shallow hip joint can cause hip dysplasia in dogs as early as 4 to 6 months of age!!
How a dog ages is another possible hereditary factor. Osteoarthritis, usually develops as a dog ages but to what degree may depend on his genes, we think…
How long the body can maintain the cartilage on the ends of bones is thought to be genetic.
Cartilage is that white, very smooth, relatively hard substance at the end of every joint that allows it to move with very little friction.
Next time you go to prepare a chicken for dinner, as you cut it in pieces look at the exposed end of the joint and maybe you will see what I mean.
In the aging process, the cartilage loses protein and gains water making it softer and easier to wear away. Once the cartilage is gone, the bones rub against each other every time the joint is moved. This causes the bone to wear away, again causing pain and bone spurs.
In addition to the genetics, there is a big environmental aspect to this illness of hip dysplasia in dogs. A gene may be present but the right circumstances allow it to be expressed in that individual dog.
Sigh, I know no one is going to want to hear this but being overweight, yes, obesity can be a big problem. More pressure on a joint and it will fail faster and easier than if less stress is placed on it.
It is a simple matter of mechanics.
I’ve mentioned elsewhere on this website about the type and extent of exercise for your Sheltie pups when they are young. Puppies should be allowed to run and play freely and puppies do jump for joy frequently. That’s not a problem.
What is a problem?
Taking your puppy jogging long distances before they are mature and growth plates in the legs have closed (finished growing) at around 18 months to two years of age in Shelties. Endurance training in general should wait ‘til then.
Agility training the jumps. Repetitive jumping at a young age can cause damage to the joints. I would think even weave poles with the rapid zigzagging could do a job on some joints. Let him learn other stuff first like the dog walk, the A frame, hoops, etc.
Most dogs, including Shelties can be pretty stoic when it comes to pain. They don’t whine or complain. Dogs just stop doing something when it hurts too bad to move.
At some point however, you may notice:
Understand that by time you see these things, your Sheltie is probably pretty far along.
How do you know for sure? Sorry guys, sometimes we need a professional to diagnose some things like hip dysplasia in dogs. The symptoms listed above could be due to other problems, such as cruciate ligament tears for example. So you need to go to your vet.
And unless you have X-Ray eyes, you need X-Rays taken at the vet’s.
No one said owning a dog is cheap.
Frequency varies based on the breed. What are the chances your Sheltie has Hip Dysplasia?
The good news is, that out of 172 breeds listed, the Shetland Sheepdog is low on the list at 148.
The percentage of hip dysplasia in dogs tested was only about 3 - 5% for Shelties.
In order for a breeder to get the best picture possible of the inheritability of hip dysplasia, obtaining hip X-rays on ALL pups from ALL litters would be ideal, but the cost and ability to get new owners to agree to this is daunting. So, most reputable breeders have to rely on testing only the parents that they use for breeding.
There are a few ways to do the evaluation. All would require an X-ray.
Have your vet complete an X-ray and give you an opinion on whether there is any dysplasia evident. I imagine most all vets would give their honest opinion, good, bad or indifferent, but if they aren’t a board certified orthopedic vet, their opinion would carry less weight. I don’t know any reputable breeders using this method.
Have your vet mail the hip X-ray they have taken to the OFA (Orthopedic Foundation for Animals), where for an additional fee, 3 orthopedic vets will evaluate the X-ray and give it a rating of Excellent, Good, Fair, Borderline, Mild, Moderate, Severe.
Inter-rater reliability of the orthopedic vets has been sited at about 95%, which is pretty darn good. Generally, what is being evaluated in the X-ray is how well the ball and socket fit together and if there is any wearing away of the bone or other bony abnormalities.
Anything less than Fair is generally considered unacceptable for breeding.
Most reputable breeders use the OFA process for screening their dogs’ hips. A preliminary test can be done before two years of age, but a final evaluation should be done after the pup reaches two.
More interesting to me was looking at a graph for Shetland Sheepdogs' OFA scores over the course of several decades. There was essentially no substantial increase in the number of “Excellent” scores over the course of decades.
This says to me that we were not doing anything helpful with this X-ray. And while it might feel good to get an “Excellent” rating for your Shetland Sheepdog, if it won't help you choose the right specimen to breed for improvement in the future generations, what’s the point?
I prefer to use this method of evaluating hips. Developed at the University of Pennsylvania in 1983, it was a newer way to measure the probability of dysplasia more accurately. Not only is the fit of ball and socket evaluated, but the laxity of the joint (how far the hip joint could be stretched away from the socket).
The greater the ability to stretch, the greater the chance the joint could wear down improperly and cause canine hip dysplasia (CHD).
It requires that the pup is anesthetized (not my favorite thing to have to do to my Shetland Sheepdogs but ya gotta do, what ya gotta do) and the X-rays performed by a veterinarian certified by PennHip.
The X-rays are then sent to the PennHip folks to be read and there are two measurements: a rating compared to other shelties, as well as an objective number for the amount of laxity of each joint.
The greater the amount of laxity in the joint, the greater the chance the dog will develop canine hip dysplasia. So this test helps in determining if a dog with good hips may eventually go bad in the future.
In addition to these two criteria, the hips are also reviewed for current hip dysplasia.
This is the test I prefer to use. Why? ‘Cause I love throwing tons of money away? (Lots more expensive than OFA, BTW).
Because I think I get better information from this type of test in spite of the low number of Sheltie breeders using it. (I swear the number of Shelties in the data base only goes up when I submit a test.)
When dealing with canine hip dysplasia, I want my breeding stock to be within the range of other shelties, preferably above the average. With subsequent generations, where both parents have been tested, improvement in distraction index is what I strive for.
The thing with any test is, you don’t want to throw the baby out with the bathwater. If, for example, a lot of Shelties have loose hips and you take ALL of those out of the gene pool, there won’t be anything left to breed. It would be the proverbial genetic bottleneck.
Nevertheless, culling the poor specimens is necessary. ‘Tis a hard pill to swallow to see an otherwise a lovely bitch who doesn't make the grade. Been there, done that.
Think about what it’s like to choose a dog, raise her, spend $600 on a hip X-ray just so you turn around and sell her as a pet because her hips aren’t good enough. UGH!
People tend to think breeding dogs is easy until they see the cost involved to do it right and the tough choices that need to be made when testing reveals a problem. But if those tough choices weren't made, the result could be someone stuck with a puppy that quickly turns into a debilitated mess.
The other point to keep in mind is, you can't cull if you don't know where the problems lie. And with the traditional OFA (Orthopedic Foundation for Animals) hip dysplasia Xrays there hasn't been the betterment of the hips in decades, so that is simply throwing good money after bad.
But, you say, evaluating canine hip dysplasia is as easy as looking to see your sheltie running and jumping effortlessly. He has to have good hips, right? Why X-ray at all?
I had an English Shepherd bitch evaluated using PennHip when she was 1 ½ yrs old. She could fly over farm gates and run like the wind. She could go all day long. And she already had evidence of hip dysplasia on the films.
No way would I breed her. I sent her back to the breeder from whence she came. And he promptly bred her. Can't cure stupid...
Finally, I like PennHip better when dealing with canine hip dysplasia because the X-rays can be reliably done as early as 16 weeks old. I prefer to wait until older, but there is no guesswork as to the soundness of hips before they are used for breeding.