FIGURE 112.22 A: Normal anteroposterior (AP) (open-mouth, odontoid) view of C1 and C2 C , first cervical vertebra (lateral mass); C , second cervical vertebra; T, central incisors overlying dens (D ); and A, normal relationship between lateral mass of C1 and vertebral body of C2 B: Jefferson fracture in AP view Note lateral offset of C1 on C2 (arrows ) C: Jefferson fracture Computed tomography coronal view Note three distinct fractures (arrows ) and bursting nature of injury D: Pseudo-Jefferson fracture of childhood in a 3-year-old child because of disparate growth of C1 and C2 and cartilage artifact (arrows ) E: Pseudo-Jefferson fracture demonstrating marked offset of the lateral masses of C1 on C2 (arrows ) (B , C : Reprinted with permission from Swischuk L Emergency Radiology of the Acutely Ill or Injured Child 2nd ed Baltimore, MD: Williams & Wilkins; 1986:591 D : From Aslamy W, Danielson K, Hessel S, et al A 3-year-old boy with neck pain after motor vehicle accident West Med J 1991;155(3):301–302 Copyright BMJ Publishing Inc Reprinted with permission.)