The term congenital dislocation of the hip dates back to the time of Hippocrates. This condition, also known as hip dysplasia or developmental dysplasia of the hip (DDH), has been diagnosed and treated for several hundred years. Most notably, Ortolani, an Italian pediatrician in the early 1900s, evaluated, diagnosed, and began treating hip dysplasia. Galeazzi later reviewed more than 12,000 cases of DDH and reported the association between apparent shortening of the flexed femur and hip dislocation. Since then, significant progress has been made in the evaluation and treatment of DDH.
The definition of DDH is not universally agreed upon. Typically, the term DDH is used in referring to patients who are born with dislocation or instability of the hip, which may then result in hip dysplasia. More broadly, DDH may be defined simply as abnormal growth of the hip. Abnormal development of the hip includes the osseous structures, such as the acetabulum and the proximal femur, as well as the labrum, capsule, and other soft tissues. This condition may occur at any time, from conception to skeletal maturity. The author prefers to use the term hip dysplasia, considering it both simpler and more accurate. Internationally, this disorder is still referred to as congenital dislocation of the hip.