**1. Introduction**

The developmental dysplasia of the hip (DDH) includes a wide spectrum of abnormalities of the acetabulum and the proximal femur, including dysplasia, subluxation and dislocation of the femoral head [1–5].

In dysplasia, there is an inadequate development of the acetabulum, the femoral head or both, although there is also a concentric relationship between the 2 articular surfaces. However, in subluxated hips, although there is contact between both articular surfaces, the femoral head is not centered on the acetabular cavity [6]; in the case of dislocation the femoral head is completely out of the acetabulum [7].

Early diagnosis in the first months of life, before the child can walk, is essential, since some children with DDH go unnoticed, despite having used the usual clinical procedures, which only diagnose subluxation or dislocation, and when starting ambulation, the hip joint is injured and cannot be treated with orthopedic measures, and may lead to surgical repair of the joint; In extreme cases, the femoral head becomes necrotic, which requires the placement of a prosthesis.
