Mechanisms of action of thyroid hormones in the skeleton

► Thyroid hormones regulate bone development, peak bone mass and adult bone turnover. ► Thyroid hormone deficiency and excess are associated with increased fracture risk. ► Euthyroid status is essential for normal bone development and maintenance. ► TRα mediates the major actions of T3 in the skeleton. ► T3 exerts anabolic effects during growth but catabolic action in the adult skeleton.