Anterior inferior iliac spine avulsion injury

Anterior inferior iliac spine (AIIS) avulsion injuries are one of the six main types of pelvic apophyseal avulsion fractures

As with many pelvic avulsion injuries, they most often occur in adolescents (mostly between the ages 14-17). There is a slight male predilection and they tend to occur most often in sports involving kicking.

The straight head of the rectus femoris muscle originates from the AIIS and forceful extension at the hip joint can lead to an avulsion injury at this point.

Plain radiograph

The avulsed bony fragment may not be as obvious on the AP radiograph as on oblique projections.

Almost all cases are managed conservatively.

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Article information

rID: 909
Section: Pathology
Tag: refs
Synonyms or Alternate Spellings:
  • AIIS injury
  • AIIS avulsion injury

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