Derelopmentat Dysplasia Hip (DDH) is a common disorder in which the head of the femur gradually becomes subluxed due to long-term biomechanical abnormalities caused by congenital developmental defects of the acetabulum, degeneration of the cartilage in the weight-bearing area and focal necrosis of the head of the femur, which develops into severe osteoarthritis. The anatomical basis of normal mechanical stability is altered by hip dysplasia, which is characterized by a shallow flat acetabulum, thinning of the anterior wall, thickening of the posterior wall, sloping changes in the upper edge of the true socket, the presence of bone defects and osteosclerosis; contracture of the periarticular ligaments, and thickening and expansion of the joint capsule. The posterior wall of the left acetabulum accommodates the lack of acetabular coverage in front of the femoral head, and it is easy to dislocate the left hip osteoarthritis, and the femoral head is visible as cystic changes Pelvic orthopantomographs measure the difference in length of the bilateral lower extremities, measured as the difference in vertical distance from the apex of the lesser trochanter to the line of the bilateral sciatic tuberosity.