Purpose Open surgery, nonsurgical positioning device and casting are mainstay treatments of developmental dysplasia of the hip (DDH). The optimal indicators for surgical interventions remain unclear. In this study, we aim to establish empirical, sensitive radiographic indicators for periacetabular osteotomy intervention in developmental dysplasia in Chinese children. Methods One hundred and three DDH patients treated in The Soochow University Children's Hospital between 2006 and 2012 were assessed; patients with known causes of neuron muscular and abnormal hip joint origin were excluded. Fifty-four suitable patients, demonstrating 71 dysplasia hips with complete clinical record and adequate X-ray films, were enrolled in this study. Patients were divided into group A (conservative interventions failed, followed by salvage periacetabular osteotomy) and group B (conservative treatment only); a total of 16 quantitative parameters were measured on each pelvic X-ray film. Results Among 71 hip joints measured, 29 hips of group A underwent salvage peri-acetabular osteotomy (40.8 %,) showed higher X2, Y, h, and Smith c/b (Vh) (p<0.05). The age, c, HT, b, A2 in the group A salvage operation were statistically significantly different compared to group B patients (without salvage operations) (p<0.05). Conclusions Pre-operative pelvic X-ray film assessment of acetabulum lateralization markers (X2, c, HT, c/b ratio) and the superior migration measurements (Y, h, h/b ratio) are potentially valuable radiographic indicators for determining which DDH patients will require peri-acetabular osteotomy.