Total hip arthroplasty versus hemiarthroplasty in the treatment of active elderly patients over 75 years with displaced femoral neck fractures:a retrospective study

Backgroud: Femoral neck fractures are associated with substantial morbidity and mortality for older adults. Total hip arthroplasty (THA) and hemiarthroplasty (HA) are widely used in elderly patients with displaced femoral neck fractures (DFNF), but there is still controversy refer to the optimal chose for the management of DFNF in active elderly patients. Methods：This is a retrospective cohort study that incorporates medical record review with an outcomes management database. 73 patients who underwent HA and 66 patients who underwent THA were identified from January 2015 to December 2017. Data of age, gender, BMI, comorbidity status, operation time, blood loss, hospitalization time, in-hospital complication were collected and analyzed. Follow-up clinical and radiographic examinations were performed at approximately five years,and hip complications,Harris Hip Score and EuroQol-5 Dimensions (EQ-5D) were assessed. Results: Preoperative general data of sex, age, BMI and charlson comorbidity score of THA group(n=55) has no statistically significant difference with that of HA group. Patients treated by THA had significantly longer operation time (105.5 vs 76.7 minutes;P＜0.001),more blood loss (524.1 vs 350.1ml;P＜0.001) and longer hospitalization time (15.8 vs 13.8 days;P＜0.001).There was no significant differences between two groups in complications(32.7% vs 25.8%,P=0.432). No patients died during the hospitalization. After five years,only 33 patients in the THA group and 34 patents in the HA group were still alive,and the fraction surviving were not statistically significant between two groups(60.0% vs 54.8%,P> 0.05). The differences in hip function in favor of THA appeared to increase after the five-year follow-up, and the difference was significant in terms of the total Harris hip score(81.3 vs 73.1, P＜0.001) as well as in the dimensions of pain(38.9 vs 35.9, P=0.033), function(33.7 vs 29.2, P=0.001),absence of deformity(4.0 vs 3.9, P=0.023) and range of motion(4.6 vs 4.2, P=0.008). There was no significant differences between groups in hip dislocation rate(6.1% vs 0.0%, P=0.239). The erosion rate of hip joint in the THA group was significantly lower than that of the HA group(0.0% vs 26.5%, P=0.002). The health-related quality of life, according to EQ-5D index score, was found to be higher(0.69 vs 0.63, P= 0.001) in the THA group than the HA group after five years. Conclusion: THA may be a preferred management option for active elderly patients over 75 years.The more extensive surgery of THA is not associated with higher in-hospital complication rate or mortality rate. These patients can benefit from THA in terms of hip function and quality of life. Trial registration: No.