Why does bone fracture risk increase significantly after prolonged immobilization of a limb compared to immediate weight-bearing?

💡 Explanation

Prolonged immobilization reduces mechanical loading, impairing bone remodeling by osteocytes. Decreased loading signals less bone deposition and increased resorption via mechanotransduction. Therefore, fracture risk rises because bone density declines, rather than increases caused by osteoblast activity alone.

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