History of Present Illness: A healthy right leg-dominant 13-year-old male athlete presents with left hip pain after kicking a soccer ball.
He states that he kicked the ball awkwardly and experienced hip pain immediately afterwards. He did not feel a pop or cracking sensation but could not stand after the kick and fell to the ground. He can ambulate but only with significant pain.
He now has 8/10 sharp, non-radiating left hip pain that is worse with movement, weight-bearing and palpation.
Abdominal: No wall defect on palpation, no scrotal mass and no tenderness
Musculoskeletal: Full range of motion at the hip and the knee. No ecchymosis, deformity, or edema. Tenderness to palpation at the anterior inferior iliac spine (AIIS).
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.
Take Home Points
- Consider pelvic avulsion fractures in young athletes with point tenderness at the ASIS, AIIS, or ischial tuberosity.
- Bedside ultrasound can quickly identify hematoma, and in this case, cortical bone irregularity.
- X-ray is the first choice for imaging.