Cortical bone loss in triamcinolone-treated mice

Immature mice were treated for up to 8 weeks with daily doses of triamcinolone diacetate. The humerus was studied radiographically at regular intervals. Roentgenographic measurements included midshaft width, medullary width, cortical thickness and total length. By the time of the tenth injection significant cortical bone loss was noted, followed by increased width of the medullary cavity and osteoporosis. An initial phase of active endosteal bone resorption was replaced by a prolonged steady state which extended throughout the experimental period. Possible explanations for the above findings are discussed.