The hip joint is a ball and socket joint. Normally, a ball atop the thighbone sits squarely and firmly in a socket at the hip. Hip dysplasia occurs when this connection is loose or does not exist. Untreated this condition can create severe problems. So, early detection and treatment are strongly recommended. Hip dysplasia runs in families and tends to affect girls and first-born infants more often than other children. Treatment depends on the patient’s age and the condition’s nature. Often, for babies six months and under, doctors try to correct the situation, using a harness. This keeps ball and socket in the right position and encourages normal alignment. Children above six months of age may require surgery and the subsequent use of a body cast. As with the harness on younger children, surgery’s goal is correct ball-socket placement.