High failure rates of metal-on-metal hip arthroplasty implants have highlighted the need for more careful introduction and monitoring of new implants and for the evaluation of the safety of medical devices. The National Joint Registry and other regulatory services are unable to detect failing implants at an early enough stage. We aimed to identify validated surrogate markers of long-term outcome in patients undergoing primary total hip arthroplasty (THA). We conducted a systematic review of studies evaluating surrogate markers for predicting long-term outcome in primary THA. Long-term outcome was defined as revision rate of an implant at ten years according to National Institute of Health and Care Excellence guidelines. We conducted a search of Medline and Embase (OVID) databases. Separate search strategies were devised for the Cochrane database and Google Scholar. Each search was performed to include articles from the date of their inception to June 8, 2015.Objectives
Methods
In In a hip fracture experiment, nine pairs of human cadaver femurs
were tested in a paired study design. The femurs were then re-matched
according to BMD, creating two new test groups. Intra-pair variance
and paired correlations in fixation stability were calculated. A
hypothetical power analysis was then performed to explore the required sample
size for the two types of group allocation. Objective
Methods