Hip Dysplasia
Hip dysplasia is an abnormal development or growth of the hip joint and usually occurs on both sides of the animal. There is laxity and instability (or looseness) of the joint which can develop into malformation of the hip and femur (long bone of the leg) resulting in arthritis. It is mostly a problem in large breed dogs and has a genetic component. It is also influenced by rapid growth (which can be related to diet or genetics) and excessive exercise. Due to the genetic component of the disease, dogs with known hip dysplasia should not be bred. It is a very rare condition in small dogs (less then 25 pounds) and cats.
Some dogs with hip dysplasia will never show signs of hip pain, while some dogs will show signs as early as 4 months of age. Clinical signs include a reluctance to rise, an altered gait, obvious lameness in a back leg, an inability or reluctance to climb stairs, poorly defined muscles of the hind legs, pain upon touching the hip, and even excessive chewing above the hips. Dysplastic dogs often have a shortened hindlimb gait.
Diagnosis is made by the results of a complete orthopedic exam and hip x-rays. Sedation is almost always required to get appropriate views of the hips. The veterinarian will look for signs of arthritis in the joint as well as deviations from normal in the joint space. Sometimes when the dog is sedated a click can be heard when moving the joint in specific directions; this is called an Ortaloni sign.
Treatment will depend on the severity of the disease, the presence of arthritis, the financial constraints of the owner, and the dog's lifestyle. Dysplastic dogs with no signs require no treatment other than keeping their weight low and limiting hard impact exercise. Swimming is good for dysplastic dogs. Dogs with mild signs can be treated with pain medication (Rimadyl®, Etogesic®, aspirin) and maintaining a proper weight. There are some nutritional supplements that may also be helpful. Examples of these include Cosequin®, MSM, and Glycoflex® and Synovi-Crea®. For dogs with moderate to severe signs that do not respond adequately to pain medication , or for dogs who are young and the owner wants to slow the progression of the disease, there are surgical treatments for hip dysplasia. The three most common will be touched upon here. For young dogs with no signs of arthritis a Triple Pelvic Osteotomy (TPO) is an option. This involves breaking the pelvis and reshaping it to form a better joint. For older dogs a Total Hip Replacement is possible. Both of these procedures can be done on one or both sides and have a high success rate. Yet, they are expensive ($2000-3000) and require a surgical specialist to perform them. The third procedure, often called a salvage procedure, is Femoral Head and Neck Excision. This involves removing the femoral head, or ball component of the ball and socket hip joint. A false joint is created by the muscles and tendons. These dogs often have a permanently altered gait, but they are pain free. Talk with your veterinarian about whether or not these options are suitable for your dog.
Hip dysplasia is a progressive disease, but, as stated previously, some dogs will never show signs. Prognosis depends on the dog and the degree of laxity, the presence of arthritis, the dogs' weight and its ability to control its weight, whether or not surgery is an option, and the dogs lifestyle.
Any large breed dog that is to be bred should have an OFA radiograph exam of their hips at two years of age. This requires sedation and can let the veterinarian know if an asymptomatic dog has hip dysplasia that it might pass on to its offspring. A dog with hip dysplasia should not be bred. Another radiographic exam called the PennHip procedure can be done at an earlier age to check for hip dysplasia, but this procedure is not readily available.