The Use of Ultrasonography in Expediting Septic Joint Identification and Treatment: A Case Report

This case report describes the use of ultrasonography in the identification of a joint effusion to guide diagnosis and management of septic arthritis. Our patient presented with pain, swelling, and erythema of the right thumb after having punctured her thumb with a cactus thorn. Results of physical examination demonstrated tenderness and restricted range of motion. Initial imaging with plain films was unrevealing, without bony and soft tissue abnormalities; however, ultrasound imaging of the interphalangeal joint revealed a focal effusion, and the patient was started on empiric Keflex. Because a focal effusion was visualized with ultrasonography, despite negative x-ray imaging, our patient underwent expedited surgical incision and drainage, foregoing joint aspiration. Intraoperative cultures grew Enterobacter 3 days after surgery, and the empiric antibiotic was adjusted to reflect sensitivities. At 2-wk follow-up, our patient showed near-complete resolution of her symptoms. This case report demonstrates the utility of ultrasonography in the early diagnosis of septic arthritis with the presence of a joint effusion that expedited successful treatment by foregoing joint aspiration in lieu of surgical intervention.