What does it mean to fracture a bone?

Fracturing a bone specifically refers to the condition where the bone's continuity is compromised, resulting in a break. This can happen due to various causes, including trauma, stress, or medical conditions affecting bone density. A fracture can range in severity from a hairline crack to a complete break that may misalign the bone fragments.

In the context of the other options, strengthening a bone indicates a process of increasing its density, which does not relate to fracture. Twisting a bone typically describes a motion that could lead to a fracture but does not define the action of fracturing itself. Aligning a bone involves repositioning it back to its normal structure, usually after a fracture has occurred. Therefore, the essence of what it means to fracture a bone is accurately captured by stating that it refers to a break in the bone.