Emergency department ultrasound diagnosis of spontaneous iliopsoas haemorrhage in a patient on warfarin.

A 87-year-old man presented to the emergency department (ED) with right-sided abdominal and thigh pain which had been present for the last 3 days and was getting worse. He had been diagnosed with a deep venous thrombosis of the left common femoral and superficial veins 10 days previously and had been discharged on a loading dose of warfarin and low-molecular weight heparin (dalteparin) injections. Despite his international normalised ratio being only 2.4, an ED ultrasound showed an unusual mass in the right iliac fossa, partly cystic and partly solid. A CT scan was performed which showed the lesion was a haematoma in the right iliopsoas muscle mass.