case_images: PMC6431363_01
case_images: Lateral cervical X-ray at the first visit to our hospital showing instruments on C1/C2, O-C2 angle of 17-degree kyphosis, and vertical subluxation: Redlund-Johnell's distance, 22 mm. Space available for the cord (SAC), atlantodental interval (ADI), and C2-7 angle are 15 mm, 2 mm, and 33 , respectively.
case_images: CRIOR2019-7982847.001.jpg
case_images: PMC6431363_01_CRIOR2019-7982847.001.jpg
case_images: fig1
case_images: Lateral cervical X-ray showed O-C2 angle of 17-degree kyphosis (Figure 1).
case_images: Computed tomography (CT) of the cervical spine showing erosion of anterior arch of C1 vertebra and dens (black arrow).
case_images: CRIOR2019-7982847.002.jpg
case_images: PMC6431363_01_CRIOR2019-7982847.002.jpg
case_images: fig2
case_images: Computed tomography (CT) showed an erosive lesion at dens and anterior arch of the atlas (Figure 2).
case_images: Sagittal T2-weighted image of magnetic resonance imaging of the cervical spine at the first visit showing a mass on retropharyngeal space with heterogeneous intensity (white arrow).
case_images: CRIOR2019-7982847.003.jpg
case_images: PMC6431363_01_CRIOR2019-7982847.003.jpg
case_images: fig3
case_images: Magnetic resonance imaging showed a space-occupying lesion in the retropharyngeal space, which presented with heterogeneous signals on both T1- and T2-weighted images (Figure 3).
case_images: Lateral cervical X-ray after the posterior O-C3 fusion surgery at our hospital showing O-C2 angle of 6-degree lordosis.
case_images: CRIOR2019-7982847.004.jpg
case_images: PMC6431363_01_CRIOR2019-7982847.004.jpg
case_images: fig4
case_images: The O-C kyphosis was corrected to 6-degree lordosis on O-C2 (Figure 4).