A 45-year-old male with a recent history of orthopedic surgery presents to the emergency department with a swollen, painful right calf. His vital signs are stable and he denies chest pain or shortness of breath. What would be the BEST next step in the management of this patient?
Advise elevation of the extremity and application of a warm compress.
Perform a D-dimer test to rule out deep vein thrombosis.
Order a duplex ultrasonography to assess for presence of a thrombus.
Initiate anticoagulation therapy immediately to prevent clot propagation.