Different indicators are measured in different examinations for babies. Taking ultrasonography as an example, the normal range of the α-angle of the hip joint as measured by the Graf-Graf method should be above 60°. Ultrasound is commonly used to determine the development of the hip joint in infants and young children, not only to observe the bony structure, but also to observe the cartilage and other structures. When ultrasound is used, the Graf-Graf method is commonly used for evaluation. The α angle is an indicator for evaluating the bony acetabular development of the hip joint, and the normal range of the α angle of the hip joint as determined by the Graf-Graf method in normal children should be above 60°; the β angle is an indicator for evaluating the development of acetabular cartilage of the hip joint, and the normal value of the β angle needs to be analyzed according to the specific α angle. If the α angle is above 60° and the β angle is above 55°, the overall development of the hip joint is good; if the α angle is less than 50°, no matter what value the β angle is, it is abnormal, which indicates that there is a possibility of hip dislocation. If there is any abnormality in the hip joint examination, it is recommended to go to the hospital in time.