ObjectiveTo explore the cause of prosthesis dislocation after primary artificial hip replacement (AHR) and propose preventive measures. MethodsA total of 221 patients underwent artificial hip replacement from 2000 to 2012, among whom 8 developed dislocation. These cases were retrospectively analyzed to summarize the causes of dislocation and preventive measures were proposed. ResultsAmong 221 cases of hip replacement, 8 suffered from postoperative dislocation. All of them underwent posterolateral-approach total hip arthroplasty. The causes of dislocation included coexisting decreased muscle strength before operation, improper placement of the prosthesis during operation, inappropriate postural changes after operation, improper nursing and health education. Of the 8 dislocation cases, 2 were cured after reoperation and revision, 6 were cured through close reduction under anesthesia, and 7 were followed up for 1-5 years without relapse. ConclusionPreoperative assessment of the patients' soft tissue tension of affected hip and comorbid conditions, selection of proper design of prostheses and the components, removal of tissues possibly causing joint impact, correct placement of artificial prosthesis and components and instructing the patients for the correct movement mode of the affected hip after operation are all crucial for the prevention of postoperative hip dislocation.