According to Wolff's Law, handedness results in thicker and stronger bone of which limb?

• A. The upper limb of the dominant hand
• B. The lower limb of the dominant leg
• C. Both upper limbs equally
• D. The spine

Answer: (A)

Wolff's Law says bone remodels in response to the mechanical loads it experiences, becoming thicker and stronger where there is more stress. Because handedness means the dominant hand is used more and with greater repetitive forces, the bones of that upper limb undergo more remodeling. This increased loading leads to greater cortical thickness and higher bone density in the dominant arm (humerus, radius, ulna), making it thicker and stronger than the non-dominant side. The lower limb and spine aren’t specifically loaded more because of hand use, so they don’t show the same asymmetrical adaptation. In short, the upper limb of the dominant hand becomes thicker and stronger due to the greater mechanical stress it routinely experiences.