Hidden blood loss and its influencing factors after minimally invasive percutaneous transpedicular screw fixation in thoracolumbar fracture

Abstract Objective: This study aimed to investigate the amount of hidden blood loss (HBL) and its influencing factors after minimally invasive percutaneous transpedicular screw fixation (MIPTSF) in thoracolumbar fracture.Summary of Background Data: MIPTSF is generally accepted as a minimally invasive treatment for thoracolumbar fracture. However, HBL caused by this procedure is usually disregarded.Materials and Methods: Between October 2017 and December 2020, a total of 146 patients (106 males and 40 females, age range 21–59 years) were retrospectively examined, and their clinical and radiological data were recorded and analyzed. The Pearson or Spearman correlation analysis was used to investigate an association between patient’s characteristics and HBL. Multivariate linear regression analysis was performed to elucidate the related clinical or radiological factors of HBL.Results: A substantial amount of HBL (164.00 ±112.02 ml, 40.65% of TBL) occurred after transpedicular screw internal fixation. Multivariate linear regression analysis revealed that HBL was positively associated with total blood loss (TBL) (P=.000), percentage of vertebral height loss (VHL) (P=.000), percentage of vertebral height restoration (VHR) (P=.000), numbers of fractured vertebrae (P=.013), and numbers of fixed vertebral segments (P=.002).Conclusion: A large amount of HBL was incurred in patients undergoing MIPTSF in thoracolumbar fracture. More importantly, TBL, percentage of VHL, percentage of VHR, the numbers of fractured vertebrae and fixed vertebral segments were independent risk factors for HBL.