Risk Factors for Deep Vein Thrombosis in Hospitalized Patients With Periarticular Knee Fractures Caused by High-Energy Injuries.

This study examined the incidence of in-hospital deep vein thrombosis (DVT) and its associated factors in patients with periarticular knee fractures caused by high-energy injuries. A total of 151 patients treated between January 1, 2020, and December 31, 2025, were retrospectively enrolled. Lower-extremity colour Doppler ultrasonography was performed during hospitalisation, and patients were classified into DVT and non-DVT groups.Thrombus location and clinical variables were recorded. The in-hospital DVT incidence was 32.5% (49/151). Thrombus distribution was predominantly distal: muscular veins 73.5%, peroneal veins 36.7%, posterior tibial veins 28.6%, and popliteal veins 20.4%. femoral and iliac veins were less frequently involved. Univariable analysis showed that age, complex fracture type, fractures at other sites, diabetes mellitus, Injury Severity Score (ISS), time from admission to operation, and admission D-dimer were significantly different between DVT and non-DVT groups (P < 0.05). In this exploratory multivariable model, age (OR 1.05, 95% CI 1.02-1.09, P = 0.001), complex fracture type (OR 2.62, 95% CI 1.10-6.29, P = 0.030), and ISS (OR 1.25, 95% CI 1.12-1.40, P < 0.001) were independently associated with in-hospital DVT. A nomogram combining these three factors showed good discrimination in this exploratory analysis (AUC 0.821, 95% CI 0.749-0.892), with calibration and decision curve analysis confirming its clinical utility. In conclusion, patients with high-energy periarticular knee fractures have a substantial risk of predominantly distal in-hospital DVT. Advancing age, fracture complexity, and higher ISS independently increase this risk. This exploratory nomogram may assist in risk stratification, but prospective and external validation are required.