Evaluation of X-ray, Acetabular Guides and CT in THR

Total hip replacement is one of the most successful surgical procedures of modern times, with over 80,000 performed each year in the UK. However, up to 5% of all primary hip replacements need to be revised within the first 10 years, and in many cases malposition of the acetabular (hip socket) component is implicated in the early failure. The standard method of positioning the acetabular component is for the surgeon to be guided by a combination of the visible anatomical landmarks within the surgical field, and the wider environment of the operating theatre. The advent of 3D printing has led to the development of custom-made surgical guides which can be used during surgery, in order to assist the surgeon in the positioning of instruments and devices. These surgical guides are manufactured based on CT or MRI imaging, and are designed to clearly indicate to the surgeon the desired location and orientation of bony cuts and implant positions. This study will test the hypothesis that an acetabular alignment guide combined with three-dimensional CT-based planning using the Corin OPS™ (Optimised Positioning System), provides more accurate component alignment following primary total hip replacement compared with the current standard treatment, with the aim of improving patient outcomes and reducing the risk of complications of total hip replacement.