Fig 2. A, A 53-year-old-man after a high-velocity motor vehicle crash with head injury. Axial 2.5-mm image shows double fracture (arrows) at the transition of the body with each posterior arc of C2. Calculated effective dose of low-dose 16-MDCT examination (100 kV and 96 mAs) is 0.98 mSv. B, Coronal 2.5-mm image shows bilateral fractures at the base of each lateral mass of C2 (arrows). C, Sagittal 2.5-mm image shows fracture at the left arc of C2 (arrow) and at the left arc of C1 (open arrow). D, Sagittal 2.5-mm image shows avulsion fracture of the posterior margin of the body of C2 (open arrow) and posterior subluxation of both posterior arches of C1 and C2 (arrows).