Case 19 Answer : Vertebral (bony) hemangioma

Notice the polka-dotted or accordian-like appearance with coarsened trabeculae (vertical striations) due to the replacement of the surrounding matrix with blood. This appearance is “classic” for a benign vertebral hemangioma

Reference: http://www.learningradiology.com/archives2008/COW%20317-Hemangioma%20spine/hemangiomacorrect.htm