The anterior superior iliac spine (ASIS) is a bump on the front of the pelvic bone. It can break when a ligament (a band of tissue that connects muscle to bone) pulls strongly on the bone and causes a small piece of it to break off. This type of fracture is called an avulsion fracture.

An ASIS fracture is treated by using crutches to rest the hip, exercises or physical therapy, and pain medicines. Most ASIS fractures heal within about 2 months. If a large piece of bone broke, surgery may be needed.

Follow your health care provider's recommendations for:

• how to use the crutches so your child keeps their weight off the injured side
• how long your child needs to use the crutches 
• whether your child needs to do any exercises or go to a physical therapist
• whether your child needs to go to an orthopedic (bone) specialist
• giving any pain medicines. These may include acetaminophen (Tylenol® or a store brand), ibuprofen (Advil®, Motrin®, or a store brand), or prescription pain medicine. Some pain medicines include the same or similar ingredients. To avoid giving too much, give the medicines exactly as your health care provider recommends.
• when your child can go back to school, sports, and other activities
• when to follow up

To help with pain and swelling, put cold packs wrapped in a towel over the injured area for 10–15 minutes every 3–4 hours for the first 2 days after the injury. Do not place ice directly on the skin.

• The pain isn't controlled by the pain medicines.
• Your child has pain or swelling that gets worse.

Why are anterior superior iliac spine fractures more common in younger people? In adults, the anterior superior iliac spine is hardened bone. But in kids and teens, the bone is still growing and can be softer. This makes it more likely to be injured.

How does an anterior superior iliac spine fracture happen? It usually happens from a forceful movement like running, jumping, or kicking that makes the tendon pull strongly on the bone.