The prevalence of hip fractures is high worldwide. The numbers of annual new cases of hip fracture are more than 300,000 in the United States and more than 65,000 in the United Kingdom (Ekhtiari et al., 2020; RCP report, 2018). Hip fractures are associated with impaired physical function, pain, poorer health-related quality of life and increased cost to patients and society (Hopley et al., 2010). Displaced femoral neck fracture is one of the main types of hip fractures and requires early surgical repair because the condition (especially the Garden III or IV) is at risk of osteonecrosis (Hopley et al., 2010; Lewis et al., 2019). Surgery options include total hip arthroplasty (THA), hemiarthroplasty (HA) and internal fixation. It has been found that in older patients, arthroplasty (either THA or HA) is superior to internal fixation (Lewis et al., 2019). The choice of a specific surgery depends on...