Which statement best defines Wolff's Law?

• A. A bone grows or remodels in response to forces or demands placed upon it
• B. Bones shrink with underuse
• C. Remodeling is random
• D. Bones do not change after maturity

Answer: (A)

Wolff's Law states that bone adapts to the mechanical loads it experiences. When a bone is subjected to higher strain, remodeling shifts toward forming stronger bone in the stressed areas, increasing mass and stiffness where it’s needed. Conversely, reduced loading leads to resorption and thinning, since the bone no longer needs as much strength in those regions. This process is driven by osteocytes sensing strain and signaling osteoblasts and osteoclasts to adjust the bone architecture accordingly. The idea that remodeling is random or that bones stop changing after maturity contradicts this dynamic adaptation, and saying bones shrink solely from underuse misses the active, load-driven nature of remodeling.