A 23-year-old man presented with malignant hyperthermia and a painful, swollen right shoulder. He sustained a traumatic fracture of the proximal right humerus 2 years previously. Examination revealed hot, tender swelling of the right shoulder with reduced range of movement. Radiographs showed features typical of Ewing sarcoma, and a 3-phase bone scan confirmed the presence of a primary bone tumor of the right humerus. Given the patient's high, unremitting fever, an Infecton scan was done to exclude a concomitant infection. The Infecton concentrated in the right shoulder. A biopsy of the humerus showed histopathologic features typical of Ewing sarcoma.