Why does prolonged hypocalcemia increase the risk of pathological fractures even with adequate vitamin D levels?

💡 Explanation

Prolonged hypocalcemia stimulates continuous parathyroid hormone (PTH) secretion, resulting in secondary hyperparathyroidism. This causes increased bone resorption to maintain serum calcium levels. Therefore, bone mineral density decreases, increasing fracture risk, rather than direct effects on osteoblasts.

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