Instability of total hip arthroplasty: An approach using the scientific evidence

The instability in hip arthroplasty, or joint dislocation in its most dramatic form, is a complication that changes the outcome of this procedure, causing a decrease in the quality of life of the patients, and a loss of confidence in their relationship with the surgeon. If we discount failures due to infection, dislocation is the most frequent cause of a short to medium term revision, and the number of cases that require several operations to provide stability to the joint is not insignificant. Despite the frequency and severity of this complication there are few studies with a high level of scientific evidence on this subject. We have attempted to review the published literature and its level of evidence on the pathogenic origin, prophylaxis and treatment of this eventuality. As well as recording and summarizing the findings of each study in this review, we have added the evidence level of the corresponding literature reference.