Developmental Dysplasia (DDH)Updated 7/2/09Developmental dysplasia of the hip is a congenital  condition of the hip joint. It occurs once in every 1,000 live births. The hip joint is normally created as a ball and socket joint. In DDH, the hip socket may be shallow, letting the “ball” of the femoral head slip in and out of the socket. The “ball” may move partially or completely out of the hip socket.The greatest incidence of DDH occurs in first-born females with a history of a close relative with the condition.

Hip dysplasia is considered a “multifactorial trait.” Multifactorial inheritance means that many factors are involved in causing a birth defect. The factors are usually both genetic and environmental. Often, one gender (either male or female) is affected more frequently than the other in multifactorial traits. Hip dysplasia is nine times more common in females than males.

First-born babies are at higher risk since the uterus is small and there is limited room for the baby to move; therefore affecting the development of the hip. Other risk factors may include the following:

• Family history of developmental dysplasia of the hip, or very flexible ligaments

• Position of the baby in the uterus, especially with breech presentations

• Associations with other orthopaedic problems that include metatarsus adductus, clubfoot deformity, congenital conditions, and other syndromes

While newborn screening for DDH allows for early detection of this hip condition, starting treatment immediately after birth may be successful. Many babies respond to the Pavlik harness, traction, and/or casting. Additional surgeries may be necessary since the hip dislocation can reoccur as the child grows and develops. If left untreated, the baby may have differences in leg length, and may limp.

Left untreated, DDH or hip dysplasia leads to pain and osteoarthritis by early adulthood. It may cause legs of different lengths or a “duck-like” walk and decreased agility. If dysplasia is treated successfully (and the earlier the better) children end up with normal hip joint function, have no further problems and go on to lead active lives. However, even with appropriate treatment, especially in the child who is 2 years or older, hip deformity and osteoarthritis may develop later in life.

Additional References about DHH: DHH Prevention of DHH