Sichuan University May 21 2026 Fibrous dysplasia is a rare skeletal disorder in which normal bone is gradually replaced by weak fibro-osseous tissue, leading to fractures, pain, deformities, and severe mobility impairment. In many patients, diseased bone tissue produces excessive amounts of fibroblast growth factor-23 (FGF23), a hormone that causes phosphate loss through the kidneys. Because phosphate is essential for proper bone mineralization, persistent hypophosphatemia can further weaken