Codman triangle is seen in
High-Yield Explanation
Codman triangle is a term used to describe the triangular area of subperiosteal bone that is created when a lesion, often a tumor, raises the periosteum away from the bone. Plain X-ray * Irregular destruction in metaphysis. * New bone formation. * Periosteal reaction. * Sunray appearance or hair on end - tumor grows into the overlying soft tissue. * Codman&;s triangle - area off sub periosteal new bone formation seen at the area of tumor -host coex junction. REF : MAHESWARI 9TH ED