Risk factors for implant failure in transverse intertrochanteric fractures

Abstract Background Intertrochanteric femoral fractures include transverse and reverse oblique fractures. The incidence of implant failure in intertrochanteric fractures is high. The risk factors of perforation and cutout of lag screws or helical blades in intertrochanteric transverse fractures have not been elucidated. This study aimed to retrospectively analyze the risk factors of perforation and cutout of lag screws or helical blades in intertrochanteric transverse fractures and propose an effective treatment strategy.Methods Thirty-eight patients with intertrochanteric transverse fractures who underwent surgical fixation with an intramedullary nail between 2013 and 2022 were included in this study. Patients with and without perforation and cutout of the lag screw or helical blade were grouped into group 1 and 2, respectively. To identify the risk factors of perforation and cutout of the lag screw or helical blade, age, sex, laterality, AO/Orthopedic Trauma Association classification, presence of lesser trochanteric fragments and anterior wall comminution, length and thickness of the nail, use of cement augmentation, postoperative quality of reduction, and tip apex distance were compared between the two groups.Results Perforation and cutout of the lag screw or helical blade occurred in eight cases, which were classified into group 1. Thirty patients without implant failure were classified into group 2. All eight cases in group 1 and 14 cases (46.7%) in group 2 had anterior wall comminution; group 1 had a significantly higher rate of anterior wall comminution than group 2 (p = 0.0119). There were no significant differences between the two groups in terms of items other than anterior wall comminution. Cement augmentation was not used in group 1; in group 2, it was used in eight patients. All eight patients with cement augmentation in group 2 had anterior wall comminution.Conclusions Anterior wall comminution was a risk factor of perforation and cutout of the lag screw or helical blade in femoral intertrochanteric transverse fractures. It may be possible to prevent implant failure using cement augmentation and static locking of the lag screw or helical blade at the insertion of an intramedullary nail.