Stress fracture of the pars interarticularis factsheet


A child's spine is made up of 33 small bones that link together. These bones are called vertebrae.

As your child grows into an adult, some vertebrae will fuse together, reducing the number to 24.

The vertebrae are connected with very thin pieces of bone on both sides. These are called the pars interarticularis.

Stress fracture of the pars interarticularis is a condition where there is a break or fracture in the pars interarticularis on one or both sides. This type of fracture usually happens in the lower part of the spine, called the lumbar region, which goes from the lower back to the bottom. 

This condition is also known as:

  • a pars defect
  • spondylolysis.

A stress fracture in the pars interarticularis can develop after repeated, ongoing strain, like in sports or physical activity. Activities that cause these fractures usually involve bending, stretching, or twisting the lower back. 

Activities can include:

  • cricket
  • gymnastics
  • diving
  • soccer
  • weight lifting
  • tennis.

Some children are born with weakness in their spine, which means they can develop the condition even if they do not do sports or physical activity.

Children and teenagers are generally more at risk for stress fractures in the pars-articularis because their bones are still growing. They are also more likely to play sports and do physical activity regularly.

 Signs and symptoms

Symptoms of a stress fracture in the pars interarticularis generally include pain:

  • in one or both sides of the lower back
  • that spreads to the bottom
  • that gets worse with bending backwards, standing for long periods and running
  • that slowly gets worse over time rather than starting suddenly.

See your local doctor or physiotherapist as soon as possible if your child starts to develop pain or discomfort during sports and activities, even if it is mild.


Your child’s local doctor or physiotherapist will do a physical check if they think there may be a stress fracture in the pars interarticularis. They might ask your child to bend or twist gently to see where and how severe the pain is.

If they think there is a stress fracture, your child’s doctor will order scans to make a diagnosis.

Scans can include:

  • x-rays to see any fractures in the spine
  • a bone scan to check for any abnormal areas in the bones
  • CT scans to check how severe the fracture is and whether it can heal well.


Treatment for a stress fracture in the pars interarticularis will depend on how severe the fracture is and whether the doctor thinks it can heal well.

Your child’s doctor may recommend:

  • taking a break from sports and activities for 6-12 weeks to let the bones heal
  • using a back brace to prevent any movement that will cause pain or make the fracture worse
  • seeing a physiotherapist to strengthen the muscles and improve posture
  • checking your child’s movement and pain when they go through growth spurts.

Speak to your child’s doctor about medications to help with pain or swelling.

With good rest and treatment, the fracture can heal, and your child’s pain should slowly go away.


Returning to sports and activity

The doctor and physiotherapist will let you know when your child can start back at their sports or activities. Your child will need to start very slowly to avoid the stress fracture does not get worse.

Speak to your child’s school, coaches, or other activity coordinators to make sure there is a plan in place to help your child have a safe and pain-free return to their activities.

Long-term issues with a stress fracture in the pars interarticularis

Some children are born with a weakness in their spine, which means they are more at risk of developing stress fractures in the pars interarticularis.

Stress fractures in the pars interarticularis can also develop into: 

  • long-term or chronic back pain that stops your child from being able to bend or twist properly
  • spondylolisthesis – a condition where the front part of the vertebrae slides away from the back and causes pain, muscle tightness, and nerve damage.

See your local doctor if your child’s pain does not improve after treatment. 

Preventing stress fracture in the pars interarticularis

Stress fractures in the pars interarticularis start very slowly, so it is important to set your child up with good habits to prevent the condition.

Good habits for sports and activities include:

  • taking regular breaks and stopping as soon as there is pain
  • stretching regularly
  • warming up before the activity
  • cooling down after the activity
  • using safety equipment for sport
  • keeping core muscles and posture strong
  • taking time to learn proper techniques for sports that involve strong bending and twisting movements.

Children who are born with a weakness in their spine or who have recovered from a stress fracture should avoid high-risk sports, including:

  • cricket
  • gymnastics
  • diving
  • soccer
  • weightlifting
  • tennis.
Last updated Tuesday 30th January 2024


This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2024