Patient positioning and cup orientation during total hip arthroplasty: assessment of current UK practice

Introduction: Acetabular cup orientation during total hip arthroplasty (THA) remains a challenge. This is influenced by patient positioning during surgery and the method used to orientate the acetabular cup. The aim of this study was to assess current UK practice for patient positioning and cup orientation, particularly with respect to patient supports and techniques used to achieve target version and inclination. Methods: A literature review and pilot study were initially conducted to develop the questionnaire, which was completed by British Hip Society members (n = 183). As the majority of THA surgical procedures within the UK are performed with the patient in lateral decubitus, orthopaedic surgeons who operated with the patient in the supine position were excluded (n = 18); a further 6% were incomplete and also excluded (n = 11). Results: Of those who operated in lateral decubitus, 76.6% (n = 118/154) used the posterior approach. Only 31% (n = 47/154) considered their supports to be completely rigid. More than 35% (n = 55/154) were unhappy with the supports that they presently use. The most common methods for controlling operative inclination and version were a mechanical alignment guide (MAG; n = 78/154; 50.6%) and the transverse acetabular ligament (TAL; n = 82/154; 53.2%); 31.2% (48/154) used a freehand technique to control operative inclination. Conclusion: Limited studies have been conducted whereby patient supports have been analysed and key design principles outlined. With 35.7% of the orthopaedic surgeons surveyed having issues with their current supports, a greater awareness of essential characteristics for patient supports is required.