Meta-analysis of unipolar and bipolar hemiarthroplasty for femoral neck fractures

Background: Femoral neck fracture is a common fracture in the elderly. Improper treatment seriously impacts the patient and could potentially shorten their lifespan. Hemi-arthroplasty is a common treatment for femoral neck fractures, but the selection of unipolar prosthesis or bipolar prosthesis is still a controversial issue. Therefore, we conducted this comprehensive meta-analysis to compare the outcomes of unipolar and bipolar prostheses. Methods We searched the PubMed, EMbase, The Cochrane Library, and Web of Science databases for randomized controlled trials and cohort studies comparing unipolar hemiarthroplasty and bipolar hemiarthroplasty. The revised Jadad scale or Newcastle-Ottawa Scale was used to assess the quality of the included studies. After data extraction, continuous data were expressed as standardized mean differences and binary data were expressed as odds ratio. The postoperative infection, mortality, acetabular erosion rate, dislocation rate, and Harris hip score were compared and analyzed with Stata software. Results Nineteen studies that compared unipolar and bipolar replacement were included in the meta-analysis. We found no significant differences in the postoperative infection, mortality, dislocation rate, or Harris hip score between unipolar and bipolar replacement. The rate of acetabular erosion in the unipolar group was slightly higher than that in the bipolar group. Conclusions Existing studies have revealed that bipolar hemiarthroplasty is superior to unipolar hemiarthroplasty for femoral neck fractures in terms of acetabular erosion.