Two parallel systematic reviews and meta-analyses were performed to determine the affiliation between early migration of acetabular cups and late aseptic revision. One review covered the early migration data from radio-stereometric analysis (RSA) studies (26 studies involving 700 cups), and the other focused on revision rates for aseptic loosening from long-term survival studies (49 studies involving 38,013 cups). The results showed that there was a clinically significant association between early migration of acetabular cups and late revision due to loosening; cups with proximal migration of between 0.2 and 1.0 mm were considered to be at risk of having revision rates greater than 5% at 10 years. Furthermore, cups with proximal migration of more than 1.0mm were considered unacceptable, as all of them showed revision rates of more than 5% at 10 years