IntroductionInternal fixation (IF) with cannulated screws is the most widely accepted operation method for nondisplaced femoral neck fractures (FNFs) in elderly patients. However, there were higher rate of reoperation, severe complications and poorer functional outcomes reported in these patients treated with IF. The purpose of this research is to compare the prognosis, complications, reoperation and mortality of bipolar hemiarthroplasty (HA) with IF of cannulated screws in elderly patients. MethodsAll elderly patients (>75 years of age) with nondisplaced FNFs from January 2010 to December 2015 at our institution were included in this study. Patients treated with HA and IF with cannulated screws were compared. Outcome measures included the surgical complications, perioperative parameters, hip joint function, reoperation and mortality. ResultsThe blood loss of HA group (150.0 ± 55.1 mL) was statistically more than IF group (40.5 ± 15.7 mL, p = 0.001). However, the blood transfusion rate was similar between two groups (p = 0.102). At the last follow-up, there were total 14 (34.1%) severe surgical complications in the IF group, compared to 9 (10.1%) in the HA group (P = 0.001). No difference was detected between two groups with respect to the HHS and VAS at the last follow-up. Compared with the HA group, the IF group had much more reoperation in the follow up period (p = 0.001). There was no statistically differences of mortality rate between HA group (39.3%, 35/89) and IF group (34.1%, 14/41) (p=0.571). ConclusionsAs a treatment option for nondisplaced intracapsular FNFs in elderly patients, HA showed the merits of a less surgical complications and less reoperations, while IF demonstrated a shorter surgical time and less intraoperative blood loss. Meanwhile, there was no significant difference in the hip joint function and mortality rate in midterm follow-up. Further evaluation with a longer follow-up is recommended to strengthen these findings.