case_images: PMC4234742_01
case_images: Sagittal computed tomography (CT) reconstruction images before surgery. Posteriorly displaced odontoid fracture (B) and bilateral dislocation of the C1-C2 facet joint (A and
  C) were prominent. To the right of C2, a high-riding vertebral artery (VA) was revealed (A; arrow).
case_images: 40064_2014_1360_Fig1_HTML.jpg
case_images: PMC4234742_01_40064_2014_1360_Fig1_HTML.jpg
case_images: Fig1
case_images: Cervical spine radiography and computed tomography (CT) scans revealed that C2 was fractured at the odontoid process, with 6 mm of displacement (Figure 1B).
case_images: X-ray and computed tomography (CT) images after surgery. Radiography revealed posterior fixation and reduced C1-C2 dislocation (A). Axial CT images showed posterior arch screw and lateral mass screw at C1 (B), and intralaminar screw and pars interarticularis screw at C2 (C).
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case_images: PMC4234742_01_40064_2014_1360_Fig2_HTML.jpg
case_images: Fig2
case_images: Next, using standard anatomical landmarks, a unicortical lateral mass screw was placed via the posterior arch on the left side of C1, as advocated by Tan et al. (Figure 2A and B) (Tan et al.). On the left side at C2, a pars interarticularis screw was placed (Figure 2A and C). Since a high-riding VA was seen on the right side of C2, a unicortical intralaminar screw was placed there (Figure 2C). On the right side of C1, we chose a posterior arch screw, because a lateral mass screw placed at that location could put the oldest-old osteoporotic patient at risk for a dominant VA injury if the screw ever loosened (Figure 2A and B). A 3.5-mm polyaxial screw of 12-mm length (Medtronic Inc.) was next placed at C1 (Figure 2B).
case_images: Sagittal computer tomography reconstruction images three months after the surgery. The fracture was healed (B), and the C1-C2 reduction was maintained (A, C).
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case_images: PMC4234742_01_40064_2014_1360_Fig3_HTML.jpg
case_images: Fig3
case_images: Three months after the surgery, the odontoid fracture had healed into an anatomically correct alignment, and the cervical collar was removed (Figure 3A-C).