Pediatric Pelvis and Hip Apophyseal Avulsion Fracture

• Etiology: forceful and repetitive contractions of attaching muscles at apophyses, avulsion of insertion of muscle leads to avulsion fracture
• Imaging:
  — Ischial tuberosity avulsion (54%) due to hamstrings adductors insertion
  — Anterior inferior iliac spine avulsion (22%) due to rectus femoris muscle insertion
  — Anterior superior iliac spine avulsion (19%) due to sartorius muscle insertion
  — Pubic symphysis avulsion (3%) – superior due to rectus abdominis muscle insertion, inferior due to adductor group insertion
  — Iliac crest avulsion (1%) due to transverse and oblique abdominal muscles insertion
  — Greater trochanter avulsion due to gluteal muscle insertion
  — Lesser trochanter avulsion (<1%) due to iliopsoas muscle insertion
• Clinical: avulsion and iliac wing fractures are more common than acetabular fractures and SI joint malalignment

Radiology Cases of Pelvis and Hip Apophyseal Avulsion Fracture