Thromboprophylaxis in Lower Limb Immobilisation

Inclusion Criteria: * Age \>/= 16 years * Placed in temporary lower limb immobilisation (rigid cast or brace) as a result an injury that occurred within the last 7 calendar days Exclusion Criteria: * Hospital admission is required direct from the emergency department, minor injuries unit, or fracture clinic setting with an expected length of stay \>2 calendar days. * Absolute contraindication or known hypersensitivity to anticoagulants, including history of end stage renal failure (eGFR \<20ml/min/1.73m2), hepatic failure or use of concomitant systemic treatment with azole-antimycotics (such as ketoconazole, itraconazole, voriconazole and posaconazole), HIV protease inhibitors (e.g. ritonavir) or active substances strongly inhibiting elimination pathways such as CYP3A4 or P-gp (such as clarithromycin, erythromycin or dronaderone) or a history of heparin induced thrombocytopenia. * Pregnancy, actively seeking conception, or active breastfeeding. * Preceding use of anticoagulant treatment for \>3 calendar days at prophylactic or therapeutic dose. * Prior enrolment in the TiLLI study. * Non-rigid immobilisation (crepe bandage, tubigrip support, strapping). * Time since prescription of rigid immobilisation \>3 calendar days * Co-enrolment onto a CTIMP where an anticoagulant is administered * People lacking the capacity to consent * Inability or refusal to use acceptable contraception up until after the last administration of IMP. Only applicable for women of childbearing poten…