Total hip arthroplasty planning.

Preoperative planning is mandatory to achieve the restoration of a correct and personalized biomechanics of the hip.The radiographic review is the first and fundamental step in the planning. Limb or pelvis malpositioning during the review results in mislead planning.Correct templating is possible using three different methods: acetate templating on digital X-ray, digital 2D templating on digital X-ray and 3D digital templating on CT scan.Time efficiency, costs, reproducibility and accuracy must be considered when comparing different templating methods. Based on these parameters, acetate templating should not be abandoned; digital templating allows a permanent record of planning and can be electronically viewed by different members of surgical team; 3D templating is intrinsically more accurate. There is no evidence in the few recently published studies that 3D templating impacts positively on clinical outcomes except in difficult cases.The transverse acetabular ligament (TAL) is a reliable intraoperative soft tissue reference to set cup position.Spine-hip relations in osteoarthritic patients undergoing hip joint replacement must be considered. Cite this article: 2019;4:626-632. DOI: 10.1302/2058-5241.4.180075.