A hip fracture is a large burden to the patient with increased mortality, pain and increased need for daily assistance. Trochanteric fractures of the femur (FTF) represents about 35% of the hip fractures. Today FTFs are mainly treated with internal fixation using sliding hips screws (SHS) or intramedullary nail (IMN), whilst hip arthroplasty (THA/HA) is rarely used. Despite advances in the design of the internal fixation implants there is a high failure rate, in particular in cases of FTFs classified as unstable fractures. Since the introduction of hip arthroplasty in femoral neck fractures there has been a reduction in complication rates, early mobilization and shorter hospital stays. The primary objective of this project is to investigate if treatment with hip arthroplasty in unstable FTFs will increase the postoperative mobility, give a better general health outcome for the patient, better quality of life and reduce re-operation rate for the patients compared to those operated with the traditional IMN.