Clinical development of ileofemoral thrombosis caused by malposition of the ileosacral screw

Abstract

Introduction Treatment of unstable injuries of the pelvic bones is one of the unsolved problems in modern traumatology. The instability of the injuries is determined by the nature of the destruction of the posterior semi-ring of the pelvis. The most used technique for osteosynthesis of sacral fractures for unstable pelvic injuries is ileosacral screw fixation.The purpose of the work was to demonstrate a clinical case of an iatrogenic complication: ileofemoral thrombosis caused by compression of the internal iliac vein due to malposition of the ileosacral screw.Materials and methods Medical records of a 34-year-old patient injured in a traffic accident (front seat passenger) were studied, who was referred from a district hospital on the fourth day after the injury diagnosed with a fracture of the transverse process of L2 vertebra on the left, closed fracture of the pubic and ischial bones on the left, fracture of the lateral mass of the sacrum on the right. Alcohol intoxication. Traumatic shock stage 1. Treatment results were monitored throughout the inpatient and outpatient treatment periods. Long-term follow-up was 6 months.Results Timely suspicion of the complication based on physical examination data with CT angiography that assisted to exclude internal bleeding and urgently carry out repeated surgical intervention to correct the  implant malposition, reosteosynthesis of S1 body without loss of reduction, to achieve regression of the clinical picture of ileofemoral thrombosis, and also to mobilize the patient in the shortest possible time. During inpatient treatment, regression of the symptoms of the complication was achieved, the patient was fully activated, and was discharged for outpatient follow-ups.Discussion Variability in the anatomy of the sacrum and the characteristics of fractures hinder the navigation while inserting iliosacral screws, which in some cases result in malposition. Compression of the common iliac vein without damaging it causes difficulty in blood outflow and the development of a clinical picture of ileofemoral thrombosis in the early postoperative period.Conclusion This clinical case shows that X-ray images in standard views are not a reliable method for diagnosing sacral injuries and are not sufficient for preoperative planning. The use of standard C-arm did not provide sufficient intraoperative visualization to correctly assess the position of the iliosacral screw, especially in cases with sacral dysmorphia. The 3D volumetric image reconstruction significantly influenced the correct perception of the anatomical structure of the bony structures of the pelvis. Malposition of the screw and its exit to the anterior surface of the sacrum caused disruption of the iliac vein outflow and development of thrombosis in the early postoperative period.