Intraarticular Osteoid Osteoma Associated with Synovitis: A Possible Role of Cyclooxygenase-2 Expression by Osteoblasts in the Nidus. - Kawaguchi,Y.; Sato,C.; Hasegawa,T.; Oka,S.; Kuwahara,H.; Norimatsu,H. (Mod Pathol, 2000)