What is Hip Dysplasia?
Hip dysplasia is an abnormal development and growth of the hip joint. Both hips are usually affected, but only one side may show symptoms. When both sides are affected, the onset of clinical signs may not occur on both sides at the same time. Hip dysplasia is manifested by varying degrees of laxity of the muscles, ligaments, and joint capsule of the hip joint. This abnormal laxity allows the femoral head (ball) to slide in and out of the acetabulum (socket) excessively, resulting in malformation of the joint components. Arthritis is the long-term consequence of undetected or untreated hip dysplasia.
Hip dysplasia occurs primarily in dogs that have a mature body weight of over 30 pounds. However, toy breeds and even cats have been reported to have the problem. Hip dysplasia is a genetic problem.
We recommend orthopedic screening examinations at 6 months of age in medium, large, and giant breed dogs. Hip certification radiographic examinations by the Orthopedic Foundation or Animals (OFA) for breeding purposes are not performed until dogs are 24 months old and older.
The clinical signs, of hip dysplasia, lameness and pain, can be evident as early as four to six months of age. The symptoms can initially be as subtle as: stiffness in the morning, slowness to get up, not wanting to exercise as long or as vigorously, a change in stride of the hind legs, "bunny hopping", wanting to sit down while eating or during walks, or reluctance to stand up on the hind legs. Sometimes the only observation is an "inactive" or "laid back" puppy. The symptoms may not be present until a dog is middle-aged or older.
What are treatment options for hip dysplasia?
Several treatment options are available for treatment of hip dysplasia. Young dogs (usually 6-12 months of age) that do not have advanced arthritic changes are candidates for a reconstructive procedure to save the hip. This procedure is called a triple pelvic osteotomy (TPO).
A total hip replacement (THR) is a treatment option if the components of the hip joint are worn or deformed from the ravages of arthritis and/or treatment of pain is unsuccessful. We do not recommend salvage procedures, such as removal of the femoral head, in dogs that have uncomplicated hip dysplasia and are large enough to accept the hip prosthesis. Ask for more information if your dog falls into this category.
What is a triple pelvic osteotomy (TPO)?
Triple pelvic osteotomy means cutting the pelvis in three places. The osteotomies, or cuts, are preformed to allow rotation of the acetabulum into a better position over the femoral head. Thus, the femoral head is "captured" within the acetabulum to stabilize the hip joint. A stainless steel plate specifically designed for this procedure holds the repositioned acetabulum while the osteotomies heal.
Why perform a triple pelvic osteotomy?
In puppies, the joint instability associated with hip dysplasia is painful and disrupts normal development of the hip joint. A triple pelvic osteotomy is performed to relieve pain, restore function, and, stabilize the hip joint so it, will develop more normally. Studies in human and in dogs show that if the abnormal weight-bearing forces across the joint are corrected early in the course of hip dysplasia, a more "normal" articulation will develop.
It is important to realize that the objective is to stabilize the hip joint to prevent the debilitating arthritis of chronic dysplasia. The emphasis must be on early detection and intervention before severe joint damage occurs.
Is your dog a candidate for a triple pelvic osteotomy?
A triple pelvic osteotomy must be preformed before arthritic changes become too advanced. Ideal candidates are usually 5 to 8 months of age. Puppies of susceptible breeds should be evaluated by their veterinarian by 6 months of age. Many 8-12 month old dogs are still candidates, but most dogs older than 12 months of age are not. Occasionally, dogs less than 8 months old are not candidates if their hip dysplasia is severe. Some dogs may be a candidate in one hip but not the other.
The most important criteria for candidate selection is hip palpation under general anesthesia. Properly positioned radiographs taken under anesthesia are also mandatory. Definitive patient selection and surgical planning (i.e., the number of degrees the acetabulum will be rotated) are based on hip palpation by the surgeon immediately prior to surgery. If both hips require reconstruction, surgery is performed on the most severely affected side first. The second side is done 2 to 6 weeks later.
What do dogs experience to get a triple pelvic osteotomy?
The surgery takes approximately 90 minutes. Isoflurane general anesthesia is used. Vital parameters, such as heart rate, heart rhythm, tissue perfusion, respiratory rate and pattern, temperature and blood pressure are continuously monitored. Detailed attention is paid to preoperative preparation of the patient, instrument preparation, aseptic technique, and environment control in the operating room.
Pain medication is administered postoperatively and maintained as long as needed. The patient is hospitalized with 24-hour patient care. The dogs routinely support some weight on the leg immediately postoperatively. They are generally released from the hospital one or two days following surgery.
What can I expect after the operation?
Most dogs walk on their newly positioned hip joint immediately after surgery. Patients should remain inactive for 6 weeks postoperatively. They should remain indoors, but allowed outside on a leash to eliminate. Short leash walks are allowed after 3 weeks. If necessary, tranquilizers are prescribed. Gradual return to normal activity is allowed between 6 and 8 weeks postoperatively.
Most dogs show a significant improvement in attitude, personality, and activity levels. In instances of severe dysplasia, marked improvement in walking, sitting, climbing stairs, standing, running, getting into the car, playing, and performance can be expected. Most dogs lead a normal, active life following TPO.
Are there any risks?
Yes. The incidence of complications is very low, but risks exist just as they would for surgery on people. Complications from infection, technical problems, and anesthesia can never be totally eliminated. Extreme precautions to minimize infection and anesthesia problems are taken. With owner and patient compliance, complications rarely occur.
When should the surgery be performed?
Surgery options must be considered as soon as early hip dysplasia is detected. Unless dysplasia is exceptionally severe, patients are allowed to reach an age of 6 months to improve bone quality (young puppies have very soft bone). It is important to realize that some patients are candidates at age 6 or 7 months, but may not be at age 9 or 10 months due to the advancement of the dysplastic process. In general, surgery should be performed as early as possible.
