Purpose: To evaluate the clinical and radiological results of hip arthroplasty using a cementless modular femoral stem in patients older than 70 years with a femoral neck fracture.
Materials and Methods: From January 2002 to May 2005, 67 hip arthroplasty procedures (66 patients) using a cementless modular femoral stem for displaced femoral neck fractures in patients older than 70 years of age were evaluated. All the patients were followed up for more than 2 years. The mean age at surgery was 77 (70~92) years. There were 22 men and 44 women. The mean follow up period was 31 months (24~41). The clinical evaluation was performed by examining the perioperative Activities of Daily Living (ADL) and postoperative complications. The radiological evaluation for femoral stem loosening and osteolysis was performed using the serial postoperative radiographs. The radiological evaluation for leg length discrepancies was performed using the immediate postoperative radiograph.
Results: In preoperative ADL, 31 cases (46%) were in grade 1, 21 (31.5%) in grade 2, 14 (21%) in grade 3, 1 (1.5%) in grade 4 and none in grade 5. A review of the postoperative ADL revealed 25 cases (37.5%) in grade 1, 18 (27%) in grade 2, 21 (31%) in grade 3, 3(4.5%) in grade 4 and none in grade 5. Postoperative restoration of the ADL was observed in 48 cases (71.5%). There were no significant complications. Radiographically, all cases showed stable bony fixation of the femoral stem with the exception of 1 case, who showed subsidence and a pedestal reaction. Postoperative leg length discrepancy was observed in 5 cases (7.5%) but was < 1 cm in all cases.
Conclusion: In elderly patients older than 70 years of age with a displaced femoral neck fracture, cementless hip arthroplasty using a modular femoral stem provides good initial stability and subsequent secure bony fixation with minimal complications.

Keywords: Displaced femur neck fracture, Hip arthroplasty, Cementless modular femoral stem