TRiP-cast Score Validation and Evaluation of Adherence to Preventive Anticoagulant Treatment in Patients With Lower Limb Trauma Requiring Immobilization

This is a prospective, multicenter, observational cohort study designed to externally validate the Trauma-Related Immobilization-related Prophylaxis (TRiP(cast)) score in Tunisian adults with acute lower-limb trauma requiring immobilization and managed as outpatients. The study will assess the ability of the TRiP(cast) score to identify patients at increased risk of symptomatic venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism. A secondary objective is to evaluate adherence to prescribed thromboprophylaxis and to compare adherence between patients receiving low-molecular-weight heparin (LMWH) and those receiving direct oral anticoagulants (DOACs). Factors associated with treatment adherence, bleeding events, and thromboembolic outcomes will also be investigated. Patients aged 18 years or older with acute lower-limb trauma requiring immobilization for at least 7 days will be enrolled consecutively and followed prospectively. The decision to prescribe thromboprophylaxis and the choice of anticoagulant will remain entirely at the discretion of the treating physician according to routine clinical practice. Study investigators will not influence treatment decisions. The results are expected to provide external validation of the TRiP(cast) score in the Tunisian population and improve risk stratification and thromboprophylaxis management in ambulatory patients with lower-limb trauma.