Early reoccurrence of traumatic posterior atlantoaxial dislocation without fracture: A case report

Figure 1 Radiographs on admission. A and B: Computed tomography scans of midsagittal and coronal sections showing posterior atlantoaxial dislocation without fracture; C and D: T2W magnetic resonance imaging (MRI) midsagittal and T1W MRI coronal views showing signal changes with no cord edema but transverse ligament rupture.

Figure 2 Radiographs after closed reduction. A: Lateral X-ray showing 11 mm atlantodental interval and 32 mm atlantoaxial interval of C1-C2; B and C: Computed tomography scans of coronal and midsagittal sections showing return of the odontoid process into the C1 ring with asymmetric lateral atlantodental spaces.

Figure 3 Radiographs after re-dislocation. A: Lateral X-ray showing complete posterior dislocation of the atlantoaxial joint; B: Computed tomography scan of coronal section; C: Three-dimensional reconstruction showing C1-C2 re-dislocation without any associated fractures.

Figure 4 A cervical fixation system with four C1-C2 pedicular screws and autologous iliac bone grafts.

Figure 5 Radiographs 12 mo after internal fixation. A: Lateral X-ray showing normal atlantoaxial complex, perfect positioning of pedicular screws, and good bone fusion; B: T2W magnetic resonance imaging (MRI) midsagittal; C: T1W MRI coronal views showing normal cervical spinal curvature and positioning of the odontoid process in the C1 ring without cord edema.