Bone Outcomes, Obesity, Sunlight, and Trauma in Children

Prospective case-control study of children (3-15 years) after low-energy trauma. We compare serum bone metabolic markers (25OHD, PTH, ALP, calcium, phosphate), BMI/percentile, and dietary calcium intake between fracture and non-fracture presentations. Blood is collected within 7 days (non-fasting; samples on ice for PTH). Primary aim: association of ALP and calcium with fracture status; secondary aims: vitamin D status, BMI percentile, and a composite Bone Risk Score (≥3). Analyses: group comparisons, logistic regression, ROC.