A common question I get from parents is, “Is it healing?”. Here’s how your doctor can tell.
Clotted blood that forms at the broken ends of a bone is part of the normal healing process. The clot doesn’t travel anywhere, and the bone can’t heal without it. The blood clot forms a kind of web or scaffold that helps the healing cells know where to go.
New bone cells eventually form in and around this congealed blood around the break. This is called callus (pronounced Cal-us; cal like California)
The callus is forming, even though we can’t see it immediately on x-ray.
Looking at x-rays
Eventually the callus turns bright on x-ray – meaning that it’s calcifying and getting more solid. Usually we can see hard callus forming at around 2 or 3 weeks in a child’s arm.
Just because there’s callus (new bone) on the x-ray doesn’t mean the break has healed all the way.
Touching the arm
The second and very important way your doctor can tell if your child’s break has healed is by touching the area where the bone was broken.
If gentle pressure on the broken/healing area causes no pain, and new bone has formed on the x-rays, the fracture is healed. This usually happens around 5 or 6 weeks after a break in a child.
Sometimes if there’s lots of new bone on the x-ray, but the arm is still tender or painful to touch, the cast isn’t necessary but your doctor may recommend a splint for a couple of weeks while the bone finishes healing.
These situations involve discussions about whether your child can keep a removable splint on or whether it’s just safer to keep a cast on for another 2 weeks.
I usually check kids back in the office after the final couple of weeks to make sure the arm isn’t tender any more.