Ultrasound-guided screw fixation for patellar stress fracture in a female basketball player: A case report

Introduction: Stress fracture of the patella is an overuse disorder that occurs in the lower extremity. Surgery may be considered if conservative treatment does not work or if a quicker and more reliable return to sports is expected. Surgery is usually performed under fluoroscopic guidance based on the premise that the proper placement of the internal fixation material can be determined on radiographic images. Patient concerns: A 16-year-old female basketball player gradually became aware of pain in the anterior aspect of her right knee during basketball, without any particular history of trauma. A computed tomography scan revealed a small bone fragment on the lateral side of the distal end of the patella. Diagnosis: Stress fracture of the patella. Interventions: Since it was difficult to determine the exact location of the bone fragment on radiographs, the surgery was performed under ultrasound guidance rather than fluoroscopy. While checking the bone fragment with ultrasound images, insertion of the guide pin, drilling, and screw fixation were performed under ultrasound guidance. Outcomes: Postoperative computed tomography showed accurate screw insertion into the bone fragment. Two months after surgery, bony fusion was confirmed, and the patient returned to her preinjury level of basketball. Conclusion: Ultrasound-guided screw fixation was useful in this case in which internal fixation of fractures is difficult under fluoroscopic guidance.