title: Heterotopic ossification heralded by a knee effusion.
abstract: A knee effusion suddenly appeared in a 44-year-old woman one month after she suffered a neurological catastrophe. Heterotopic ossification (HO) subsequently developed above her knee. Because treatment of HO with disodium etidronate may be successful if started early, awareness of the association between acute arthritis and new bone formation in certain clinical settings is important.
mesh_terms: D000328:Adult; D001933:Brain Stem / Q000473:pathology*; D002544:Cerebral Infarction / Q000150:complications*; D004487:Edema / Q000209:etiology; D012968:Etidronic Acid / Q000627:therapeutic use; D005122:Exudates and Transudates / Q000378:metabolism*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology*; D009999:Ossification, Heterotopic / Q000209:etiology*
chemical_list: D012968:Etidronic Acid