Surgical outcomes of retrograde nailing enhanced with minimally invasive cerclage cable fixation for infra-isthmal femoral fracture

Background: Infra-isthmal femoral fracture has been known as one of the risk factors for femoral nonunion. Retrograde intramedullary nailing can provide reliable stability of the distal fragment in infraisthmal femoral fracture, but adequate reduction is required to achieve a successful outcome. This study aimed to evaluate the surgical outcomes of retrograde nailing enhanced with minimally invasive cerclage cable fixation for infra-isthmal femoral fracture. Methods: Between March 2013 and July 2017, 15 patients with infra-isthmal fractures treated with retrograde nailing and minimally invasive cerclage cable fixation were included in this study. Cerclage cable was applied for reduction aid (reduction cable) or prevention of further displacement in nondisplaced extension of the distal spiral fracture (prevention cable). Number and function of cerclage cables, operation time, additional surgery, and complications were assessed. Further displacement of the wedge after nailing, coronal and sagittal alignment, displacement of the main fragment, and time from injury to union were evaluated as radiologic outcomes. Results: Of the 15 patients in this study, 14 were treated with reduction cables. Average postoperative coronal and sagittal angulation was 1.7 degrees (1 degrees varus to 4 degrees valgus) and 1.6 degrees (2 degrees flexion to 11 degrees extension). Mean displacement between the main fragments was 3.5 mm (range 0-22 mm). Four of the 14 cases used additional prevention cables combined with reduction cable. Only one case was treated solely with a prevention cable. A total of five prevention cables were maintained without further displacement. All patients achieved bone union, and the average time to union was 22.7 weeks (range 9-44 weeks). There were no complications as a result of surgery, such as infection or major neurovascular injury. Conclusions: The minimally invasive cerclage cable technique could be a useful and safe enhancement in retrograde nailing for infra-isthmal femoral fracture in order to prevent further displacement and to reduce the main fracture. (C) 2021 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.