Change of the Halo Sign and the Grafted Bone according to the Usage of Teriparatide for the Correction Loss due to Screw Loosening after Corrective Osteotomy

ABSTRACT

Among osteoporosis medications, Teriparatide is an agent that promotes bone formation and it seems to have an effect, due to an anabolic mechanism, in the early postoperative period after osteosynthesis or joint replacement. But to the best of our knowledge, the effect of teriparatide on pedicle screw loosening has not been previously reported. We report there on a case of pedicle screw loosening after corrective osteotomy in a patient with ankylosing spondylitis with osteoporosis, which was not improved by teriparatide, and we review the related literature.