Hip dysplasia in dogs: Thoughts on incidence, treatment and prevention
Posted Oct 19 2008 11:53am
This past month I’ve seen more hip dysplasia cases than I can recall having seen all summer. Maybe it’s the ever-so-slight change in the Miami weather that’s messing with my patients’ joints. Or perhaps it’s just a rash of bad luck.
Whatever the case, the influx of hip patients has again driven me to the keyboard to explain the disease…and to ponder why hip dysplasia is still so prevalent—and so misunderstood—in spite of thirty years of increased awareness of its effects.
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.
And this is where I find my clients confused: Some tend to think that over time, rubbing and grinding might lead to a smoothing-out of the joint. Instead, the body reacts to the ill fit of the joint by trying to stabilize it. In essence, the body produces hard, bony material in and around the joint so that the hip doesn’t move as much and therefore won’t cause the animal so much pain.
That’s why dogs with hip dysplasia don’t tend to show obvious pain as much as they do creakiness, weakness and a limited range of motion. That’s one way of looking at it, anyhow.
But that doesn’t mean there’s no pain. In fact, as any human with arthritis will tell you, pain is a huge part of their life. No, they won’t burst into tears at the grocery store or while watching TV, but they will tell their friends, family and doctors about it.
We veterinarians don’t have the luxury of having pets tell us of their discomfort, just as owners of pets with severe hip dysplasia may not even know it’s there. They won’t usually howl or whine. They won’t typically whimper or even lick their sore spots (though some do). What they will do is…
1) move less, play less, and generally develop a “couch-potato” lifestyle
2) lose muscle mass in their hind legs
3) have a harder time getting up
4) slip on slick floors
5) limp or bunny-hop when they walk or run
6) gain weight everywhere except where it counts—in their thighs
The cases that most commonly come our way are the slowly-declining dogs that suddenly have a much harder time getting up. It’s pretty sad to see a severely affected older dog who’s been suffering from severe arthritis secondary to hip disease—which no one ever noticed before. Everyone thought she was just aging less gracefully than others…or simply inclined to indolence.
Then there are the very young cases, the dogs whose hips are so poorly fitted that even before they hit puberty they’re already showing signs of disease. They run funny, limp along occasionally, etc. but almost never will these more exuberant examples cry, either.
Whichever the case, young or old, pain relief through medication is the most common prescribed course of treatment. A close second is the obvious solution: euthanasia. While surgery is often the ideal approach for most severe sufferers—and it is for those young dogs who will eventually join their ranks—it’s the least common course we take.
The expense and perceived eventuality is the biggest reason why surgery for hip dysplasia is declined—as in, “We always knew Fluffy would end up like this so why prolong the inevitable with prohibitively expensive surgery?” Or its corollary: “She’s too young to expect her to suffer all her life with this.”
Moreover, the extreme efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) like Rimadyl and Metacam (despite the railing against them that occurs on Dolittler and other pet health sites for their numerous side effects) has changed the medical landscape for these dogs. Instead of hobbling along piteously at four or five years old, these dogs now power through until they’re ten or eleven—as long as the everlasting font of medication doesn’t run dry.
And yet we know that if we must medicate them daily in order to keep them functional there’s something really wrong here…
I’ve been working in a veterinary private practice setting for more than twenty years (most of them as a doctor) and it’s clear that hip dysplasia has never let up. Though everyone knows that hip disease is a hereditary condition, dog breeders continue to produce animals with this trait.
To make matters worse, it’s almost as if the veterinary community has surrendered to the inevitability of hip disease, too.
Sure, our pets are living longer for our fancy care and that means we manage our hip dysplastic patients for longer periods of time (a financial boon to us vets). That may even account for why it seems there’s a neverending supply of poor hips among our canines. But, if anything, I hear less and less about putting a stop to it at its source: by controlling the genetics at its root.
In the course of my work I hear a lot of whining about the expense of medication and its side effects—not to mention the steep fees for hip surgery. Seldom, however, do I see my clients elect to proactively have their breeding pets evaluated for hip disease (even in heavily predisposed breeds). It’s rare for me to find OFA or PennHip evidence of hip soundness in the files of recently purchased purebred pups.
Yet it’s a daily occurrence, this tweaking of medications for dogs who suffer hip dysplasia. I see about five to ten new hip disease patients every month. Doing so, I’ve come to realize that I, too, have accepted the sad reality of hip disease. Could it be that we’ve really reached our limits in our ability to control hip disease? Or is it that we’re no longer willing to try…?