Figure 1 Imaging evaluation and guided intervention for femoral neck fracture nonunion. (A) An anteroposterior pelvic radiograph taken 9 months after injury shows internal fixation using an intramedullary nail, supplemented with a cannulated screw and a constrained liner for a complex right hip fracture, involving the femoral neck, intertrochanteric region, and proximal femoral shaft. A well-defined fracture line (red arrow) is visible at the femoral neck. (B) Follow-up radiograph (December 2025) demonstrates a blurred fracture line at the right femoral neck (red arrow). (C) Anterior hip ultrasound image (May 2025) illustrates the fracture line. The yellow dashed line indicates the planned needle trajectory. Anatomical labels: A – acetabulum; FH – femoral head; FN – femoral neck.