Abstract

Simple bone cysts (SBCs) are benign cavitary lesions which most commonly affect adolescent males in the first two decades of life. They are mainly asymptomatic, but can manifest with pain or pathological fractures. A 16-year old girl presented with an 8-day history of pain and swelling over the right calcaneal region. On local examination, tenderness was the only noteworthy sign and all routine laboratory tests conducted revealed normal results. Routine lab evaluations were all within normal limits. No history of trauma to the calcaneal region and no family history of other pathological conditions were reported. Despite numerous proposed methods for the management of calcaneus SBCs, the optimal approach towards these lesions remains controversial. Here, a novel method utilizing a minimally invasive technique is proposed to successfully manage these lesions. In an outpatient setting, under conscious sedation and local anestethics, two interosseous needles were simultaneously inserted percutaneously into the cyst under the guidance of CT fluoroscopy. Unlike previous techniques, aspiration was only performed to reveal serosanguineous fluid content. Then a radiopaque bone cement mixture was injected into the cyst from one needle until the cessation of serosanguineous fluid efflux from the second needle. The procedure was performed under fluoroscopy control to warrant complete replacement of cyst content with cement material. The duration of the procedure was estimated to be 15 minutes and the total dose length product (DLP) and smartview DLP were 577.9 mGy*cm and 13 mGy*cm, respectively. The patient experienced itching and warmth at the site of the procedure immediately after the intervention. 3 weeks after the procedure, the injection site healed smoothly and the patient reported pain with weight bearing activities and limping after prolonged standing. Over a one-year follow-up period, the patient recovered without any complications. Bone cement injection using a double needle technique under CT fluoroscopy guidance is a feasible and safe method to treat symptomatic unicameral calcaneal bone cysts.