Unipolar versus bipolar uncemented hemiarthroplasty for elderly patients with displaced intracapsular femoral neck fractures.

PURPOSE: To compare outcomes of unipolar versus bipolar uncemented hemiarthroplasty and determine factors affecting outcomes.

METHODS: 433 and 274 elderly patients with displaced intracapsular femoral neck fractures underwent uncemented unipolar hemiarthroplasty and uncemented bipolar hydroxyapatite-coated hemiarthroplasty, respectively. Surgical options were based on the patient's general condition and preinjury mobility status. In the respective groups, the mortality of 377 and 242 patients and the mobility of 270 and 217 patients were reviewed at the 4-month follow-up. Patient age, sex, American Society of Anesthesiologists [ASA] score, mobility, and mortality of the 2 groups were compared.

RESULTS: Patients who underwent unipolar hemiarthroplasty were significantly older, less fit, and less mobile (p<0.001). Patients who underwent bipolar hemiarthroplasty achieved better outcomes for mortality and mobility (p<0.001). Among patients who were able to walk unaided before injury, more of those having bipolar hemiarthroplasty were able to do so at month 4 than those having unipolar hemiarthroplasty (13% vs. 33%, p<0.001). Mortality within 4 months was associated with age, male gender, and ASA score. When patients were stratified according to age groups, mortality within 4 months was lower in patients having bipolar hemiarthroplasty.

CONCLUSION: In elderly patients with femoral neck fractures who were fit and physiologically young, uncemented bipolar hemiarthroplasty seemed to achieve better functional outcome.