Hip arthroplasty procedures are successful and reproducible. However, within the first two post-operative years, hip dislocations are the most common cause for revisions. This is despite the majority of the dislocations having the acetabular component within what is described as the 'safe zone'. The limitations of such boundaries do not take into account the variability of individual hip anatomy and functional pelvic orientation that exist. An alternative concept to address hip instability and improve overall outcomes is functional acetabular orientation. In this review article, we discuss the evolution of concepts, particularly the kinematic alignment technique for hip arthroplasty and the use of large-diameter heads to understand why total hip arthroplasty dislocations occur and how to prevent them.
Keywords: hip arthroplasty; hip dislocation; kinematic; kinematic total hip replacement; personalized arthroplasty.