We report a study of 168 consecutive patients (171 prostheses) with a displaced femoral neck fracture and a physiologic age older than 75 years who were treated with an uncemented bipolar Monk hard-top hemiarthroplasty. Four prostheses dislocated postoperatively, but none after discharge. Two prostheses were later extracted. Five patients sustained an ipsilateral femoral fracture. Totally, 7 patients (4 percent) were reoperated on. One year after the operation, 22 percent of the patients were dead. An increased mortality rate was recorded during the first 6 months after surgery. At follow-up 6 (3-9) years after the operation, 4 of the 62 patients alive had weight-bearing pain. Three had subsidence of the prosthesis, but none had protrusion of the acetabulum. Ninety-five percent of the patients were free from complications requiring a reoperation or outpatient evaluation.