Anterior inferior iliac spine (AIIS) avulsion fracture
Classically, specific pelvic avulsion fractures are associated with certain activities and age groups based on anatomy and the timing of closure or various ossification centers.
These fractures are seen most commonly in adolescent athletes. The AIIS is the origin of the powerful rectus femoris, and injuries are seen most frequently in soccer and sprinting. Pain, point tenderness, and swelling are common findings. Radiographs are the first choice for imaging, however, bedside ultrasound can demonstrate local hematoma and cortical irregularity keying in the diagnosis.