What exactly is fatigue fracture?

Fatigue fracture is when something breaks because it gets tired from being used over and over again.

Imagine you have a favorite toy that you shake every day to make it go boing! At first, it works great. But after a while, maybe weeks or months, the shaking starts to wear it out. One day, while you're playing, snap! It breaks in two. That’s like a fatigue fracture.

Every time you shake your toy, it goes through little bumps and squishes inside. These little stresses add up over time. Even though each shake isn’t strong enough to break the toy by itself, after many shakes, boing, boing, boing, they all work together to make the toy tired and weak.

This is just like how a bridge can get tired from cars driving over it every day. At first, it doesn’t seem like much, but after years of use, it might finally give way, crack!