Butterfly vertebra: A diagnostic pitfall on bone scintigraphy

We present a 27-year-old male patient with a diagnosis of osteosarcoma at the right tibia. The patient underwent whole-body bone scintigraphy which confirmed the osteosarcoma in the right tibia and revealed a photon deficient (cold) area at the L2 vertebra. To determine the etiology of the cold area, his recent abdominal computed tomography images were reviewed which showed a spinal congenital fusion anomaly. The typical pattern of metastases on bone scintigraphy is, increased uptake due to osteoblastic reaction but, not uncommonly cold lesions may be seen. The differential diagnosis of these lesions must be well known to prevent misinterpretations.