Slovenská chirurgia 1/2023

Incidence of Z effect after fixation of femoral neck fracture with dynamic locking plate

Aim of the study: To determine the incidence of Z effect in patients with fracture healing failure after internal fixation of femoral neck fracture with dynamic locking plate (DLP). Methods: All adult patients with a non-pathologic femoral neck fracture (FNF) and postoperative radiographic (X-ray) follow-up who underwent DLP fracture fixation at the Department of Trauma Surgery, UNLP, Košice, between 04/2014 and 04/2018 were included in this retrospective study. The presence of the Z effect was evaluated in patients with femoral head perforation. Femoral head perforation was considered to be both cut-through and cut-out type of screw cutting through the femoral head. Results: A total of 84 cases of femoral neck fracture were treated with DLP during the study period. Of these, 11 (13%) patients did not have complete documentation and 13 (15%) patients died within 6 months of surgery. Of the final 60 patient cohort, 24 (40%) cases had fracture healing failure of the FNF fracture. Non-union of the FNF fracture without perforation was found in 7 (29%) cases and perforation of the femoral head occurred in 17 (71%) cases. Z effect was identified in 2 (12%) cases of femoral head perforation. Conclusion: Z effect after osteosynthesis of femoral neck fracture with dynamic locking plate occurred in 12%.

Keywords: femoral neck fracture, osteosynthesis, Z effect