Nationwide Comparison of Cemented Versus Uncemented Hemiarthroplasty for Femoral Neck Fractures in the Elderly: A Propensity Score-Matched Analysis Using Japan's Diagnosis Procedure Combination Database

BACKGROUND: Femoral neck fractures in the elderly are a major public health issue. Hemiarthroplasty is widely used for displaced fractures; however, the optimal fixation method, cemented versus uncemented, remains controversial. In Japan, despite a high prevalence of osteoporosis, cemented hemiarthroplasty is underutilized. To date, no large-scale Japanese study has directly compared early outcomes between cemented and uncemented fixation. METHODS: We conducted a retrospective cohort study using the Japanese Diagnosis Procedure Combination database from December 2011 to March 2023. Patients aged more than 65 years who underwent hemiarthroplasty for femoral neck fractures were identified. A one-to-three propensity score matching was applied using age, sex, body mass index, and Charlson Comorbidity Index. After matching, 26,591 cemented and 79,773 uncemented cases were analyzed. Multivariate logistic regressions were used to assess early postoperative complications and in-hospital mortality. RESULTS: Cement use significantly reduced the risk of infection (odds ratio [OR] 0.747, 95% confidence interval [CI] 0.637 to 0.877, P < 0.01), periprosthetic fracture (OR 0.668, 95% CI 0.539 to 0.829, P < 0.01), and deep vein thrombosis (OR 0.683, 95% CI 0.628 to 0.743, P < 0.01). Conversely, it was associated with increased risk of transfusion (OR 1.463, 95% CI 1.418 to 1.510, P < 0.01) and cerebrovascular events (OR 1.222, 95% CI 1.061 to 1.407, P < 0.01). There were significant differences found in in-hospital mortality (OR 1.128, 95% CI 0.985 to 1.291, P = 0.082). CONCLUSIONS: Cemented hemiarthroplasty significantly lowered early mechanical and thrombotic complications without increasing in-hospital mortality. Although transfusion and cerebrovascular risks were slightly elevated, cemented fixation appears to be a safe and effective option in Japan's aging population when appropriate perioperative management is implemented.