LAUSR

OBJECTIVE The purpose of this study was to compare perioperative hidden blood loss after hip hemiarthroplasty via the SuperPATH approach and the conventional posterior approach (the Moore approach). PATIENTS AND METHODS From January 2015 to January 2017, 130 patients (80.7 ± 6.0 years) with displaced femoral neck fracture (Garden type III or IV) undergoing hip hemiarthroplasty were included in this study. As a non-randomisation study, Fifty-two patients (SuperPATH group) were operated using the SuperPATH approach, and 78 patients (Moore group) were operated with the conventional posterior approach (Moore approach). The demographic and relevant clinical information of the patients were collected. According to the combination formulas of Nadler, Gross and Sehat, the hidden blood loss (HBL) of each patient was calculated. Student's t-test for independent samples was used to compare the normally distributed variables and the Mann-Whitney U test was used to compare variables not following a normal distribution. RESULTS The visible blood loss (VBL) in the SuperPATH group was 123.7 ± 47.5 ml, the hidden blood loss (HBL) was 1084.1 ± 816.8 ml and the HBL% was 82.7 ± 16.5%. In the Moore group, the VBL was 303.6 ± 139.6 ml, the HBL was 700.2 ± 563.8 ml and the HBL% was 61.5 ± 23.8%. The patients in the SuperPATH group had more HBL and HBL% (P < 0.05). However, no significant difference was observed of total blood loss (TBL) between the two groups (P = 0.125). CONCLUSIONS HBL should not be ignored in patients who underwent hip hemiarthroplasty for displaced femoral neck fractures, as it is a significant portion of TBL. Compared with the conventional approach, the SuperPATH approach had a greater amount of HBL. A better understanding of HBL after hip hemiarthroplasty may help surgeons improve clinical assessment and ensure patient safety.