Fig. 1

a-c: Preoperative imaging. a Radiographs of the left wrist demonstrating the parosteal osteosarcoma. The two top radiographs are the original images taken before the patient was lost to follow-up. The bottom set are one year later. b MR imaging left to right show the heterogeneous T2 hyperintense and T1 isointense to hypointense, avidly enhancing exophytic cortical medullary mass emanating from the ulnar aspect of the radial metadiaphysis extending locally into the adjacent ulna. c CT three dimensional reconstruction used for operative planning