Hip Dysplasia

Hip dysplasia is a genetically determined disease that causes a malformation of the hip joint.  Faulty joint function leads to varying degrees of arthritis (also called degenerative joint disease).  Degenerative joint disease can eventually result in considerable pain and debilitation in affected dogs.  Hip dysplasia is caused by multiple genes, but scientists do not yet know which genes or exactly how many of them are involved.

No one can predict when or even if a dysplastic dog will start showing clinical signs of lameness due to pain.  Multiple environmental factors can worsen the severity of clinical signs and speed deterioration in the hip joint, including excess weight, accelerated growth rate, and high-calorie or improperly supplemented diets.  

Be alert for any stiffness in the dog's hindquarters, difficulty in getting up or lying down, or yelping or whimpering when moving the rear.  There appears to be little correlation between the severity of radiographic changes (those seen on an x-ray) and a dog's actual mobility and comfort level.  Many dysplastic dogs with extremely malformed hip joints and severe arthritis can run, jump, and play as if nothing is wrong, yet other dogs who show very little joint deterioration on film are noticeably lame.

By the time osteoarthritis shows up on an x-ray, dysplastic changes are irreversible and usually degenerative.  If a dysplastic dog has secondary arthritis and pain, most owners elect an initial treatment of weight control and exercise management.  Studies have shown that up to 76 percent of severely dysplastic dogs with arthritis secondary to HD are able to function relatively normally and live comfortable lives with conservative management.

Numerous drugs and alternative drug therapies known as "disease-modifying osteoarthritis agents" are available to control the signs of arthritis secondary to HD.  Non-steroidal anti-inflammatory drugs (NSAIDs) and glucosamine supplements are among the most popular interventions.  Several surgical procedures are currently available to help certain categories of affected dogs.  An orthopedic specialist can help determine whether surgery is a good option for your dog.  Prior to initiating any therapy, make sure that your veterinarian gathers a complete medical history and performs a thorough physical examination to help determine the best treatment for your dog.

Because hip dysplasia is relatively common in malamutes, responsible breeders screen dogs for this disorder before using them in their breeding programs.  The Orthopedic Foundation for Animals (OFA) evaluates x-rays and assigns a rating and clearance number to dogs two years and older with normal hip conformation.  When inquiring about purchasing a puppy in the United States, expect the breeder to produce clearance certificates issued by the OFA for both parents.  Another legitimate certifying body is Pennsylvania Hip Improvement Program (PennHip), but this program is relatively new.  At this time, most malamute breeders still use OFA.

Adapted from the OFA and PennHIP web sites.