Preoperative prevalence and risk factors for thromboembolic events following tibial plateau fractures: a retrospective analysis of an underestimated risk

Background Tibial plateau fractures (TPF) are complex intra-articular injuries carrying a high risk of deep vein thrombosis (DVT), muscular vein thrombosis (MVT) and pulmonary embolism (PE). Preoperative thrombosis is frequently clinically silent yet may cause serious complications, whereas its detection delays definitive surgery. This study assessed the prevalence and risk factors of preoperative venous thromboembolic events (VTE) in surgically treated TPF before and after implementation of routine duplex ultrasound screening. Methods In this retrospective single-centre study at a level 1 trauma centre, all adult patients surgically treated for traumatic TPF (AO 41B/C) between January 2015 and August 2025 were reviewed (547 patients, 554 fractures). Until August 2020 duplex ultrasound (DUS) was performed only on clinical suspicion; from August 2020 onward routine preoperative DUS was progressively implemented. VTE were confirmed by DUS or CT angiography. Prevalences are reported per fracture and patient characteristics per patient; regression analyses were performed at fracture level, except for the patient-related model. Results With DUS restricted to clinical suspicion (cohort A; 246 fractures), the detected prevalence of preoperative VTE was 3.7% (95% CI 1.9–6.8) and that of DVT 2.4% (1.1–5.2). Under routine screening (cohort B; 205 screened fractures) it was 20.0% (15.1–26.0) and 17.1% (12.5–22.8), respectively, 82.9% of DVT being distal. Given the different diagnostic strategies, this reflects the higher diagnostic yield of screening rather than a true increase in VTE. In cohort B, 28 of 41 VTE (68.3%) and 24 of 35 DVT (68.6%) were clinically silent. Two patients had in-hospital cardiac arrest from PE: one died from a DVT undetected before screening was introduced, the other had an asymptomatic DVT identified by screening. VTE was independently associated with pre-existing therapeutic anticoagulation (adjusted OR 2.96, 95% CI 1.10–7.98) and with the duration of external fixation (adjusted OR 1.11 per day, 1.02–1.20). High-grade closed soft-tissue injury (adjusted OR 2.41, 1.07–5.45), polytrauma (adjusted OR 2.24, 1.07–4.68) and initial external fixation (univariable OR 3.60, 1.76–7.35) were also associated with VTE, but none remained significant after accounting for fixation duration (adjusted OR 1.42, 0.52–3.89; 1.96, 0.76–5.05; 0.62, 0.12–3.27), i.e. risk was driven by time in the fixator rather than by external fixation as such. Conclusions Surgically treated TPF carry a substantial burden of preoperative VTE, and routine DUS reveals a high proportion of clinically silent thrombosis that would otherwise remain undetected. Severe closed soft-tissue injury, pre-existing therapeutic anticoagulation and, above all, the duration of external fixation may help to identify patients at increased risk. As two diagnostic rather than two treatment strategies were compared, the study cannot determine whether screening improves outcomes or reduces PE; prospective evaluation of structured screening and risk-adapted thromboprophylaxis is warranted.