Department of Rheumatology, Hôpital de la ville, La Chaux-de-Fonds, Switzerland.
A woman treated with fluoride for corticosteroid-induced osteoporosis presented 1 year later with an unusual localized supraacetabular followed by a same-sided femoral head fracture. Fluoride was increased in serum and urine. Transiliac bone biopsy revealed typical bone fluorosis with elevated trabecular bone fluoride.