Primary arthroplasty or internal fixation are the most common ways of treating intracapsular femoral neck fractures, while arthroplasty is the preferred salvage treatment after failed internal fixation. A prospective registration of hip hemiarthroplasties between January 1998 and March 2002 identified 282 procedures for an acute femoral neck fracture and 149 procedures after failed internal fixation with two parallel screws. Chart review was performed after 19-74 months. The groups were comparable in co-morbidities and perioperative conditions. In the primary hemiarthroplasty group 15 of 282 (5%) arthroplasties were re-operated for complications compared to 16 of 149 (11%) in the secondary group (p=0.04). The most common re-operation was soft tissue debridement because of infection. There were more patients with an excision arthroplasty as end result in the secondary hemiarthroplasty group (6 (4%) versus 1 (0.4%); p=0.004). The higher risk of a re-operation after a salvage hemiarthroplasty should be considered when deciding between internal fixation and hemiarthroplasty as treatment for femoral neck fractures.