We describe the management of a patient with a femoral fracture who had asymptomatic essential thrombocythemia. When the diagnosis of essential thrombocythemia was made, the patient was treated with plateletpheresis to reduce the platelet count before intramedullary rod fixation of his fracture. His postoperative management included the examination of his peripheral blood as well as bone marrow, which confirmed that the cause of his elevated platelet count was due to JAK2 V617F mutation that is treated by hydroxyurea and aspirin after being discharged from the hospital.