From 1.1.1984 to 31.12.1992, a total of 363 femoral neck fractures were treated by primary hip arthroplasty, with 213 total hip endoprostheses (58.7%) and 150 bipolar endoprostheses (41.3%). The average age of the 51 (14.0%) male and 312 (86.0%) female patients was 80.3 (+/- 8.9) years. While only 15.8% of all patients were treated with alloarthroplasty in 1984, the proportion treated in this way increased to 88.9% in 1992. In the same period, the percentage of patients with total hip arthroplasty who were above 80 years rose from 15.6% to 54.5% (p < 0.05), and the percentage in this group with multiple concomitant diseases rose from 28.1% to 48.2% (p < 0.05). General postoperative complications occurred after 43.5% of the operations (total arthroplasty 38.0%, bipolar prosthesis 51.3%, p < 0.01), with no substantial change during the observation period (1984-1986, 43.6%; 1990-1992, 43.2%). Surgical complications were observed in 9.1% of all cases (total arthroplasty 11.7%, bipolar prosthesis 5.6%, p < 0.05), decreasing slightly from 11.7% in 1984-1986 to 8.1% in 1990-1992. The postoperative mortality was 3.3% (total arthroplasts 1.9%, bipolar prosthesis 5.3%, p > 0.05). The higher rate of general complications and the insignificantly higher mortality after insertion of bipolar endoprostheses cannot be attributed to the endoprosthetic technique itself; they are probably due to the higher age and poorer general condition of patients in whom hemiarthroplasty was performed. Although there has been an increasing frequency of total hip replacement even in older and sicker patients in recent years, no significant changes in morbidity and mortality were observed.(ABSTRACT TRUNCATED AT 250 WORDS)