[The natural history of acetabular development in developmental dysplasia of the hip].

Normal hip joint development requires a genetically determined balance of growth between the acetabular and triradiate cartilage, and a well-centered femoral head. It is unclear how and why this delicate balance becomes disrupted, leading to abnormal development of the hip joint. It is known that, without treatment, a certain number of hips will become problematic later in life. This article outlines normal hip joint development and discusses the natural history of acetabular development in developmental dysplasia of the hip (DDH). The natural history of DDH depends on many factors including age of diagnosis, the growth capacity of the involved structures, and the effects of treatment interventions. Early identification and treatment of hip instability maximizes the chance for normal hip development to occur. However, close observation of the child is crucial to identify individuals where normal development is not occurring. Intervention may become necessary in certain situations to positively affect hip joint development.