A break or crack in a bone is called a fracture. In the case of an open fracture, it will present as an open wound or break in the skin near the site of a broken bone. In a closed fracture, the skin around the fracture is intact. However, broken bones may be unstable, causing internal bleeding, and the casualty may develop shock.
Signs and symptoms
Look for:
deformity, swelling, and bruising around the fracture
pain or difficulty moving the area
a limb may look shorter, twisted, or bent
a grating noise or feeling from the ends of the broken bones
difficulty or being unable to move the limb normally. Don't ask the casualty to attempt movement if they are unable to
a wound over the fracture when the bone is not visible or a wound where you can see the bone sticking out (known as an open fracture)
signs of shock, particularly with a fracture of a thigh bone, hip, or pelvis.

