Dog Hip Dysplasia (CHD)
Canine Hip Dysplasia (CHD) is one of the most frustrating diseases in veterinary medicine today simply because it is so difficult to prevent and treat. CHD is a developmental disease of the bones in which the head of the thigh bone poorly fits the hip socket, causing damage to the cartilage, gradual destruction of the joint, pain and swelling. This disease should not be confused with hip arthritis. Rather, it is the most common cause of arthritis in the hips.
CHD is a inheritable disease. It is passed on by the parents to the offspring. The only effective measure therefore to eradicate the disease is to prevent dogs with hip dysplasia from breeding. However, this is easier said than done, because not all dogs with hip dysplasia show signs of the disease. Seemingly normal dogs still carry the gene for CHD and are bred, causing the disease to stay within the genepool.
The best measure of prevention is of course careful breeding since hip dysplasia is a inheritable condition. The onset of hip dysplasia can be delayed in many dogs with a genetic predisposition by preventing excessive weight gain during the early months and by making sure that the puppy does not place undue stress on the hips.
OFA and PennHip offers information on breed risk. Prospective puppy buyers are advised to check for pedigrees for OFA, PennHip or GDC certifications.
A dog with hip dysplasia generally has less energy and movement. It has difficulty rising from a sitting position, lameness in the back legs, is hopping like a rabbit when running, and is reluctant to go up the stairs. However, these symptoms are usually not evident till the dog reaches middle age. In extreme cases though, some dogs exhibit obvious hip problems as early as 5-6 months of age.
Sad to say, there is no blood test or genetic test yet that will detect if a dog is a carrier of CHD or not. Diagnosis of the disease is routinely done through physical examinations and x-rays. X-rays help in assessing how bad the condition is, and through comparison with future x-rays, it can also serve as a gauge of how well the chosen treatment is working. Two techniques for taking x-rays of CHD-afflicted dogs are listed below:
1.hip-extended ventrodorsal view x-ray – Provides a frontal view of the pelvis and hip-joints and best assesses the degree of severity of arthritis present
2.PennHIP radiography technique – Used to detect hip looseness in dogs as young as four months of age.
There is no real cure for CHD just yet, but there are conservative or non-surgical ways to relieve its symptoms. These include the use of drugs to relieve pain and inflammation. Rimadyl, Ectogesic and Deramaxx are effective and have given a lot of suffering dogs the relief needed to live a normal life. Weight loss programs, controlled exercise and physical therapy are also very effective in certain cases.
When conservative treatment is not enough, the only other option is surgery. Surgery can be very effective as it corrects the underlying cause of hip pain which is a malformed joint. Surgery is approached in two different ways when dealing with hip dysplasia. Prophylactic surgery is done to prevent the progression af arthritis while therapeutic surgery aims to treat already arthritic hips.
Triple pelvic osteotomy is the primary preventive procedure available. It involves cutting the pelvis in three places and rotating the hip sockets to provide better coverage. This procedure is effective as long as it is done before arthritis sets in or before the joint is damaged. Another kind of preventive surgery, although still being studied if it is effective or not, is pubic symphysiodesis. This involves manipulating the way the pelvis grows to ensure a tighter hip. This procedure is done on very young dogs.
Therapeutic procedures include total hip replacement and femoral head ostectomy. Total hip replacement is performed mainly on larger dogs. High density, medical plastic is used to replace the socket and a high-quality, non-corrosive alloy is used for the ball. This procedure has a high success rate, almost completely eliminates pain and enables the dog to completely resume activity.
Another therapeutic procedure for hip dysplasia is femoral head ostectomy. It involves the removal of the top of the femur which then eliminates the painful grinding at the hip joint. The femur is then allowed to float freely causing the formation of scar tisue which then serves as a false joint. This procedure is not recommended for mild cases of arthritis and is generally effective only on smaller, well-muscled dogs.