Cases of femoral nerve palsy and avascular necrosis of the femoral head have been reported with the use of the Pavlik harness, but whether these cases were due to improper application of the device or a complication encountered in the course of the disorder remains unresolved. Complications arise mainly because the sheet of the iliopsoas muscle pushes the circumflex artery against the neck of the femur and decreases blood flow to the femoral head, so the Frejka pillow is not indicated in all the forms of the developmental dysplasia of the hip. Other devices employed include the spica cast, particularly following surgical closed reduction, open reduction, or osteotomy in babies and young children. Traction is sometimes used in the weeks leading up to a surgery to help stretch ligaments in the hip joint, although its use is controversial and varies amongst physicians. Surgery
In older children  the adductor and iliopsoas muscles may have to be treated surgically because they adapt to the dislocated joint position (contracture). Braces and splints are often used following either of these methods to continue treatment. Although some children "outgrow" untreated mild hip dysplasia and some forms of untreated dysplasia cause little or no impairment of quality of life, studies have as yet been unable to find a method of predicting outcomes. On the other hand, it has often been documented that starting treatment late leads to complications and ends in poor results. Hip replacement and osteotomy
Hip dysplasia is often cited as causing osteoarthritis of the hip at a comparatively young age.
Diagnosis
Most countries have standard newborn exams that include a hip joint exam screening for early detection of hip dysplasia. Sometimes during an exam a "click" or more precisely "clunk" in the hip may be detected (although not all clicks indicate hip dysplasia). When a hip click (also known as "clicky hips" in the UK) is detected, the childs hips are tracked with additional screenings to determine if developmental dysplasia of the hip is caused.Two maneuvers commonly employed for diagnosis in neonatal exams are the Ortolani maneuver and the Barlow maneuver.In order to do the Ortolani maneuver it is recommended that the examiner put the newborn baby in a position in which the contralateral hip is held still while the thigh of the hip being tested is abducted and gently pulled anteriorly. If a "clunk" is heard (the sound of the femoral head moving over the acetabulum), the joint is normal, but absence of the "clunk" sound indicates that the acetabulum is not fully developed. The next method that can be used is called the Barlow maneuver. It is done by adducting the hip while pushing the thigh posteriorly. If the hip goes out of the socket it means it is dislocated, and the newborn has a congenital hip dislocation. The baby is laid on its back for examination by separation of its legs. If a clicking sound can be heard, it indicates that the baby may have a dislocated hip.