PMC5282431_01
(a) Preoperative computed tomography (CT) of the odontoid fracture, sagittal view (left). Intraoperative view on odontoid screw placement, lateral view (right). (b) X-ray imaging disclosed a five-millimeter dorsal migration of the odontoid process three weeks after the operation, lateral view.
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A 78-year-old man, with a history of anterior screw fixation of an odontoid type II fracture after falling from a two-meter height eight years ago (Figure 1(a)), presented with newly occurred dysphagia. It is likely that the odontoid fracture was not reduced well with this surgery technique, as a five-millimeter dorsal migration of the odontoid process three weeks after the operation (Figure 1(b)) led to halo fixator installation, which had to be refixed once, for 16 weeks.
(a) X-ray imaging disclosed a ventral migration of the odontoid screw, 8 years after operation, lateral view (left) and a.p. view (right). (b) Pharyngeal stenosis was excluded by fluoroscopic swallow examination, lateral view.
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Additionally, ventral fusion of C6/C7 to C7/Th1 had been performed after traumatic fracture 32 years ago (visible on Figures 2 and 3). X-ray imaging of the symptomatic patient eight years after operation disclosed a ventral migration of the odontoid screw (Figure 2(a)). Pharyngeal stenosis was excluded by fluoroscopic swallow examination (Figure 2(b)).
(a) X-ray (left) and computed tomography (CT) (right) show missing odontoid screw and not consolidated fracture gap, sagittal view. (b) Abdomen X-rays displaying an odontoid screw in the left upper abdomen, presumably descendent colon, with no signs of free peritoneal air, a.p. view.
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The screw could not be detected anymore, the eight-year-old fracture gap was not consolidated, and the odontoid process was not dislocated (Figure 3(a)). Immediately performed chest and abdomen X-rays displayed the missing screw in the left upper abdomen, presumably descendent colon, without signs of free peritoneal air (Figure 3(b)).
PMC5282431_02
(a) X-ray (left) and computed tomography (CT) (right) show missing odontoid screw and not consolidated fracture gap, sagittal view. (b) Abdomen X-rays displaying an odontoid screw in the left upper abdomen, presumably descendent colon, with no signs of free peritoneal air, a.p. view.
CRIM2017-2923696.003.jpg
PMC5282431_02_CRIM2017-2923696.003.jpg
fig3
The screw could not be detected anymore, the eight-year-old fracture gap was not consolidated, and the odontoid process was not dislocated (Figure 3(a)). Immediately performed chest and abdomen X-rays displayed the missing screw in the left upper abdomen, presumably descendent colon, without signs of free peritoneal air (Figure 3(b)).