Alternative Names CDH, congenital dysplasia of the hip, congenital subluxation of the hip, developmental dysplasia of the hip, acetabular dysplasia
Definition This condition refers to malformation of the hip joint during foetal development. In this condition, the head of the thighbone or femur, does not sit properly in the socket of the pelvis.
What is going on in the body? Joints and bones usually grow normally during foetal development. However, in a small percentage of newborns, the pelvis has not formed its usual deep socket. Therefore, the head of the thighbone can slip partially or completely out of the socket.
What are the signs and symptoms of the condition? Symptoms vary according to the severity of the problem and the age of the person. An infant will often have no symptoms or pain. The common symptom found with congenital hip dislocation is a "click" that is heard near the hips as the hips are moved during the newborn examination.
Signs that there might be a problem include:
a baby that has odd skin folds on its thigh or trouble spreading its legs during a nappy change
a toddler that is slow to walk or walks with a limp
As the person grows older, especially in adulthood, the chances of arthritic hip pain increases.
What are the causes and risks of the condition? This condition can be caused by the way the legs of the foetus are positioned in the womb. It is more likely to occur in people with a family history of the disorder. It also affects girls more often than boys. It is three times more likely to occur in the left hip than the right. It is more common after a breech delivery, among large babies and in twins. Congenital hip dislocation is frequently associated with other conditions such as spina bifida, sternomastoid torticollis, or Down's syndrome.
What can be done to prevent the condition? There is no way to prevent this condition.
How is the condition diagnosed? Most of the time, a doctor can detect this condition when examining a newborn's hips. The doctor may do a Ortolani test, in which the thighs are spread apart, or the Barlow test, where the knees are brought together, to listen for the characteristic "click" that is heard with congenital hip dislocation.
Less evident cases can be confirmed by joint x-rays. These x-rays can be performed with the injection of dye into the hip joint. Detection can also be made by doing special tests, such as ultrasound or MRI. The earlier the diagnoses is made the better are the chances for normal hip function.
What are the long-term effects of the condition? It is possible that the hip joint will continue to develop poorly. This can result in a short leg, a limp, restricted motion of the joint, and painful arthritis.
What are the risks to others? There are no risks to others.
What are the treatments for the condition? Treatment is directed toward the development of a normal hip joint. The head of the femur and the socket of the pelvis tend to develop more normally when they are correctly positioned next to one another. This can be achieved by using extra nappies, a harness, a brace, or a cast.
If these methods don't work, the orthopaedic surgeon may recommend an operation on the hip, ligaments, and tendons, called a corrective wedge osteotomy.
A cast will be placed afterward to seat the hip properly. Follow-up joint x-rays can determine the degree of success. In young children, it may be necessary to operate on the pelvis to redirect the structures.
What are the side effects of the treatments? Side effects include possible discomfort from a brace or cast. If surgery is needed, side effects can include nausea and vomiting from the anaesthesia, and infection from the surgery site.
What happens after treatment for the condition? If treatment has begun within the first 3 months of life treatment is usually successful and no further treatment is necessary. The older a child is, the more complicated and lengthy treatment may be. Treatment may involve multiple operations and braces. Satisfactory hip function is difficult to restore if a child is older than 5.
Possible complications include:
the joint fails to respond to treatment
the hip becomes partially or completely dislocated again
How is the condition monitored? Periodic checkups with the doctor are helpful.
Author: Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
