Dreibergen Rottweilers, German Rottweilers, Rottweiler Breeder  
     
   
rottweilers and hip dysplasia
by Erika Butler - Dreibergen Rottweilers
What is hip dysplasia?
Hip Dysplasia is a genetic disease due to an abnormally developed hip joint. The cartilage that lines the joint is damaged which causes this cartilage to loose it's ability to absorb the load that is placed on the joint during movement. As the disease progresses there is inflammation and the dog's body produces new bone at the edges of the joint surface, joint capsule, ligament and muscle attachments. The joint capsule also eventually thickens and the joint's range of motion decreases.

No one can predict when or even if a dysplastic dog will start showing signs of lameness due to pain. There are multiple environmental factors such as caloric intake, level of exercise, and weather that can affect the severity of lameness and radiographic changes. There is no rhyme or reason to the severity of radiographic changes correlated with the severity of lameness. There are a number of dysplastic dogs with severe arthritis that run, jump, and play as if nothing is wrong and some dogs with barely any arthritic radiographic changes that are severely lame. Since HD is a chronic, progressive disease, the older the dog, the more accurate the diagnosis of HD (or lack of HD).

We see veterinarians OVERREACT to a diagnosis of HD all too often, frequently recommending expensive and invasive surgeries (Triple Pelvic Osteotomy, Total Hip Arthroplasty or Pectineus Tendon Surgery to name a few) when most cases can be easily managed with natural  supplements that have no side effects (MSM, Ester-C, Chondroitin, Glucosamine, Perna Mussel etc.). If you bought your dog from a reputable breeder and your dog is from good bloodlines with multiple generations of cleared ancestry, the severity of the disease is typically mild and is is rare that such extreme measures are needed to manage the disease. It is much more common to see severe forms of the disease in dogs purchased from back-yard breeders and puppy mills. If your dog is diagnosed with HD - DON'T PANIC. Talk to your breeder or someone that is knowledgeable and familiar with HD and various management options before jumping into invasive or expensive treatments.

What are the various OFA grades, and what do they mean?
Normal Hip Evaluations
Excellent -  this classification is assigned for superior conformation in comparison to other animals of the same age and breed. There is a deep seated ball which fits tightly into a well-formed socket with minimal joint space. There is almost complete coverage of the socket over the ball. OFA excellent hip rating
Good - slightly less than superior but there is a well-formed congruent hip joint. The ball fits well into the socket and good coverage is present. Statistically, most Rottweilers with normal ratings will fall into this category. OFA good hip rating
Fair - Assigned where minor irregularities in the hip joint exist. The hip joint is wider due to the ball slightly slipping out of the socket causing a minor degree of joint incongruency. There may also be slight inward deviation of the weight-bearing surface of the socket  causing the socket to appear slightly shallow. OFA fair hip rating
Abnormal Hip Evaluations
Borderline - there is no clear cut consensus between the radiologists to place the hip into a given category of normal or dysplastic. To increase the accuracy of a correct diagnosis, OFA recommends taking additional x-rays at a later date (usually 6 months). This allows the radiologist to compare the initial film with the most recent film over a given time period and assess for progressive arthritic changes that would be expected if the dog is truly dysplastic. Most dogs with this grade (over 50%) show no change in hip conformation over time and receive a normal hip rating.
Mild - there is significant subluxation present where the ball is partially out of the socket causing an incongruent increased joint space. The socket is usually shallow only partially covering the ball. There are usually no arthritic changes present with this classification and if the dog is young (24 to 30 months of age), there is an option to resubmit an radiograph when the dog is older so it can be reevaluated a second time. Most dogs will remain dysplastic showing progression of the disease with early arthritic changes. OFA mild hip rating
Moderate - there is significant subluxation present where the ball is barely seated into a shallow socket causing joint incongruency. There are secondary arthritic bone changes along the femoral neck and head (termed remodeling), acetabular rim changes and various degrees of bone pattern changes called sclerosis.
Severe - there is significant subluxation present where the ball is partly or completely out of a shallow socket. Like moderate HD, there are also large amounts of secondary arthritic bone changes along the femoral neck and head, acetabular rim changes and large amounts of abnormal bone pattern changes. OFA severe hip rating
Why isn't hip dysplasia eliminated by responsible breeders?
Unfortunately, most inherited traits, including inherited diseases, are polygenic - which means that multiple genes are involved in the inheritance of the trait and both the sire and dam must contribute one or more of the genes that cause the trait to appear in the offspring. Because a trait can skip generations it may appear to be erratic in it's occurrence.
If hip dysplasia can't be easily eliminated, why bother testing?
To date, no DNA tests have been developed to identify the specific combination of mutant genes responsible for any polygenic disorders. Therefore, we must rely on phenotypic evaluations (the external expression of a trait) to make informed decisions regarding a dog's suitability for breeding purposes. It is only through testing of individual dogs for the presence of hip dysplasia and knowledge of the prevalence of the hip dysplasia in bloodlines, related dogs and offspring that a breeder can reduce the incidence or severity of the problem.  Examination of over 3700 dogs in Switzerland has proven that 42% of all purebred dogs there are affected by HD despite control programs for the last 30 years. Breeding with dysplastic dogs and lack of progeny control are responsible for this slow progress. [M. Fluckiger, J. Lang, H. Binder, et al. [The control of hip dysplasia in Switzerland. A retrospect of the past 24 years]. Schweiz Arch Tierheilkd, 1995;243-50.]
Is it true that environmental factors can cause hip dysplasia?
Genetic hip dysplasia can not be caused by environment but environment (diet, exercise, supplementation) can make hip dysplasia more or less evident or problematic. While there are certainly other problems that can mimic the symptoms of hip dysplasia (hip or pelvic injury, crutiate ligament tear, panostiotis, normal arthritic changes due to age or excessive wear and tear on a joint etc.) a dog will not develop genetic hip dysplasia if it does not have the genes necessary to produce the trait. There are countless ongoing HD studies that are examining everything from the role of nutritional and environmental factors to the time of year that a dog is born. Environmental factors can definitely contribute to the age of onset of lameness and the severity of changes or lameness. It is very clear from the existing studies that there is a higher incidence of HD in overweight dogs but more information is definitely needed to determine if the obesity is the cause of the HD or if the obesity simply causes the HD to become evident at an earlier age. Either way, overfeeding and obesity definitely have a negative impact on HD.

Click here for an excellent article on the role of environment on hip dysplasia by Dr. Mary C. Wakeman, D.V.M.

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