Developmental dysplasia of the hip, commonly called congenital hip dysplasia, occurs when an baby's hip joint does not develop properly leaving it too loose. The most common form of developmental dysplasia of the hip is congenital, meaning it is present at birth, but hip dysplasia may also appear in children a few months or even years after birth. Developmental dysplasia of the hip is most common in babies born in the breech position (when the baby exits the pelvis feet first instead of head first), girls, and in babies where there is a family history of the condition. Treatment of developmental dysplasia of the hip depends on when it is detected and how loose the hip joint is. It can be diagnosed with an ultrasound at birth or by a physician later in life. Newborns with developmental dysplasia of the hip most often wear a special brace called a Pavlik harness, which keeps their hips in the right position to develop and heal normally. In older children, surgery may be able to correct the hip joint. If diagnosed and treated early, babies with developmental dysplasia of the hip will have normal outcomes. If not detected, children may grow up to have difficulty walking normally, which is why early detection is so important.