Case report and brief review of literature on sonographic detection of accidentally implanted wooden foreign body causing persistent sinus.

Despite advances in imaging techniques, the detection of vegetative foreign bodies in soft tissues remains a difficult and sometimes even a challenging task. Clinical evaluation of such patient may present several months or even years after the initial injury and clinician may fail to elicit an antecedent skin puncture. X-ray examination will miss radiolucent foreign bodies. A 15-year-old boy presented with a draining non-healing sinus at the lateral aspect of his right thigh for 9 months. Musculoskeletal ultrasonography was ordered after ruling out chronic osteomyelitis to detect possible lesions around the thigh. High-frequency linear ultrasonic probe readily detected an elongated foreign body within the vastus lateralis muscle. A long piece of wood was confirmed at surgery. Non-healing sinus with normal finding in radiograph following old trauma should raise the suspicion of implanted radiolucent foreign body/bodies. The role of diagnostic ultrasound as a valuable screening tool for the detection of foreign body is briefly reviewed.