Internal fixation versus total hip arthroplasty in the treatment of displaced femoral neck fractures - A prospective randomized study of 100 hips

100 patients 75 years or older, with displaced femoral neck fractures, were randomly assigned to osteosynthesis with two parallel and percutaneously i nserted screws (Olmed) or total hip arthroplasty (Lubinus IF). Mean age was 84 (75-101) years, 74% were women and 45% had mental dysfunction. General complications were commoner in the arthroplasty group but the mortality rat es did not differ. In the osteosynthesis group, fracture complications were seen in 27/50 hips. In the arthroplasty group, dislocation was the main co mplication and occurred in 11/50 cases. At 3 months and after 1 year, the H arris Hip Scores were significantly better in the arthroplasty group. When mental dysfunction was present, the dislocation rate after arthroplasty was 32%, whereas the reoperation rate after osteosynthesis was 5%. The opposit e pattern of complications was found in patients with normal mental functio n, 12% versus 60%. The 2-year mortality rate among those with mental dysfun ction was 26/45, compared to 7/55 of those with normal function (p < 0.001) . We conclude that total hip arthroplasty should be considered for a displa ced femoral neck fracture in old patients with normal mental function and h igh functional demands.