A few of my readers have written to me asking about hip dysplasia, a deformity of the hip that occurs during growth in some dogs. To get a better understanding of this disease, I consulted with Dr. Michel Selmer, DVM at Advanced Animal Care Center in Long Island, NY. Following are answers to my questions:
Pet News and Views: What is hip dysplasia?
Dr Selmer: The hip joint is a ball and socket joint, and during growth both the ball (the head of the femur or thighbone) and the socket in the pelvis must grow at equal rates. In hip dysplasia uniform growth does not occur resulting in laxity of the joint followed by degenerative joint disease or arthritis, which is the bodies attempt to stabilize the loose hip joint. The degree of lameness that occurs is dependent on the extent of these arthritic changes and may not be correlated with the appearance of the hip joint on x-rays. Some pets with significant signs of hip dysplasia on x-rays may not exhibit any clinical signs while others with minimal changes may experience severe pain and lameness.
PNAV: What causes it?
Dr. Selmer: There are two primary causes of hip dysplasia, genetics and diet. The genes involved have not been conclusively identified, but it is believed to involve more than one gene. Advances in nutritional research have shown that diet plays an important role in the development of hip dysplasia. Large breed puppies should be fed a special diet during the first year of life to reduce this risk.
PNAV: If it is hereditary, are certain breeds affected more than others?
Dr. Selmer: Yes, although any dog can be affected, it is predominantly seen in larger dogs such as German Shepherds, Saint Bernards, Labrador Retrievers, Golden Retrievers, Old English Sheepdogs, and Bulldogs. Mixed-breed large dogs are also at risk for developing hip dysplasia and should also be fed a special large breed growth diet the first year.
PNAV: What symptoms should we look for?
Dr. Selmer: Weakness and pain in the hind legs are the usual clinical signs. The dog appears wobbly and is reluctant to rise from a sitting or lying position. This can be seen in puppies a few months old but is most common in dogs one to two years of age. Dogs with mild hip dysplasia on x-ray may develop minimal arthritis without clinical signs until they are older.
PNAV: How is it diagnosed?
Dr. Selmer: A hip radiograph is the preferred method for diagnosing hip dysplasia. Clinical signs and palpable joint laxity may also indicate hip dysplasia. Any pet suspected of having hip dysplasia should be radiographed as soon as possible.
PNAV: What is the treatment?
Dr. Selmer: This depends upon the pet’s clinical signs and amount of discomfort. There are very effective non-steroidal anti-inflammatory drugs (NSAIDs) that have minimal side effects. The choice of medication is made on an individual basis and various drugs may need to be tried before finding the most effective one. Most dogs with hip dysplasia should receive veterinary-approved glucosamine-chondroitin sulfate nutritional supplements.
PNAV: What if NSAIDs don’t help?
Dr. Selmer: The alternative to NSAID therapy is surgery. There are several surgical procedures available to treat hip dysplasia. The two most surgical techniques for hip dysplasia are total hip replacement and femoral head ostectomy (FHO). The choice of surgery will be determined by your pet’s condition and lifestyle.
PNAV: What else can I do to reduce the risk of hip dysplasia?
Dr. Selmer: Large breed or at-risk puppies should be fed a special large-breed growth diet during their first year of life. Your veterinarian will give you specific feeding guidelines to ensure that you are providing the best care for your dog.
To my readers: I interviewed Dr. Selmer earlier about stem cell and platelet therapies for dogs with hip dysplasia. You can read this article here.
I also want to mention that cats can get hip dysplasia too, although it is more common in dogs. And if any of you have advice for the few readers who are trying to help their dogs with hip dysplasia, please share.