Abstract:Objective To explore the value of Graf's ultrasound in the early diagnosis and follow-up of developmental dysplasia of the hip (DDH) in infants, and to provide a theoretical basis for early detection of DDH or the first choice of high-risk neonatal screening in infants aged 0-6 months in the future. Methods From March 2021 to August 2021, 408 infants with 0-6 months examined in the child care clinic of the Maternal and Child Health Center of Nanjing Jiangbei New District was selected. Graf method was used for ultrasound DDH screen, and the results of DDH screening and follow-up were statistically recorded and analyzed. Results There were 45 infants with DDH, involving 53 hip joints, and the total detection rate was 6.50% (53/816). physiological immaturity was present in 35 cases, and intervention required in 10 cases. DDH was more common on one side and was statistically more on the left than that on the right（P=0.016). Type ⅡB, ⅡC and D hips were mainly found on the left. The incidence of DDH in female infants was higher than that in males (P=0.004). Of 48 DDH hips followed up, there were 36 cases of natural development and maturity in 38 physiologically immature hip joints (94.74%,36/38). The natural outcome rate was 77.08% (37/48), and the rate of clinical intervention treatment was 22.92% (11/48). Conclusion Graf ultrasound is non-invasive, convenient, and reproducible method and has important application value in the early screening and treatment follow-up of DDH in infants aged 0 to 6 months.