He walked with an antalgic gait. Right tibia measured 2 cm longer than left. A and B, Anteroposterior and lateral radiographs of tibia reveal lesion in distal metaphysis. Lesion has led to bowing of fibula, giving evidence of long history and benign nature. C, CT scan shows lesion more clearly; it proved to be osteoblastoma. D, Typical microscopic appearance of osteoblastoma.