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HealthInfo West Coast-Te Tai Poutini

Fractured forearm in children

Your child has broken a bone in their forearm by falling on to their arm. Fracture is another word for break.

There are two bones in the forearm: the radius and the ulna. When children break these bones there can be two types of breaks or fractures. In greenstick injuries the bones bend quite badly and partially break, but do not snap right through. Or the bones may break through and get quite badly out of line.

Because children's bones are still growing, doctors try to avoid doing an operation with plates and screws to line the bones up. Instead, they prefer to pull the bones back into line (giving the child a light anaesthetic) and then plaster the arm to hold everything in position.

Children's bones don't need to be perfectly aligned for them to heal. They have so much growing to do that their body manages to remodel the bones over time into a straight bone.


If the injury is more than 2 to 3 cm away from your child's wrist, in the middle of their forearm, or close to their elbow, the plaster will go up above their elbow. This stops their arm moving at the elbow, and keeps the break properly lined up. If the break is nearer their wrist, they might get a new cast, which stops below their elbow, a few weeks later.

The plaster cast may have a cut in it to allow for swelling. This cut will be joined up either before your child goes home, or at their first visit to Orthopaedic Outpatients Clinic.

At first it is important to encourage your child to keep their arm raised up on pillows and to pump their fingers. This helps to decrease their swelling.

Before your child goes home they will have an X-ray in the cast to make sure the break is properly lined up.

At home

Make sure your child has regular pain relief. Paracetamol or codeine is best. Your child should take it as the doctor has prescribed. You'll find more helpful information on the Care of your cast page. Please read it carefully.

If you have any concerns phone:

Emergency Department

Buller Hospital (03) 788‑9030

Grey Base Hospital (03) 769‑7400

and ask to speak to a registered nurse.


At their second or third visit to the Orthopaedic Outpatients Clinic your child's cast might be changed to a lighter, coloured one. We can't change the cast too early as this might make the broken bones move and cause some pain to your child.

Your child can go back to school once the pain has settled and their arm is no longer swollen (about a week after the injury). It is best to keep the arm in a sling, or collar and cuff to stop it being knocked while they are at school.

Information provided by the Canterbury DHB. Adapted by the West Coast DHB. Page created June 2016.


Page reference: 275613

Review key: HISAA-362960