A 69-year-old woman presented to the Emergency Department (ED) after several months of atraumatic, progressive right foot and ankle pain. On physical examination, she had swelling and point tenderness posterior and inferior to the lateral malleolus, which was exacerbated by eversion. Plain radiography of the foot and ankle showed only soft tissue swelling. Bedside ultrasonography performed by the emergency physician quickly identified findings consistent with peroneal tenosynovitis without tears. Management with a walking boot and nonsteroidal antiinflammatory drugs was initiated prior to discharge.
In this case of peroneal tenosynovitis, point-of-care ultrasonography was used to promptly and accurately identify hyperemia, synovial thickening, and a marked effusion within the right peroneal tendon sheath. Nonoperative treatment of tenosynovitis was initiated in the ED while findings were subsequently confirmed with magnetic resonance imaging. Emergency physicians should be aware of the utility of identifying tenosynovitis by point-of-care ultrasonography, which can expedite nonoperative management and prevent long-term complications.