Single door laminoplasty plus posterior fusion for posterior atlantoaxial dislocation with congenital malformation: A case report and review of literature

Figure 1 Preoperative images. A: Parasagittal computed tomography (CT) showing the posterior atlantoaxial dislocation combined with os odontoideum; B: Axial CT scan, demonstrating the C1 inner sagittal diameter (white line) = 22.51 mm and the canal sagittal diameter (black line) = 12.00 mm; C: Parasagittal magnetic resonance imaging.

Figure 2 Images of reduction. A: Lateral radiographs 4 d after traction; B: Lateral radiographs 8 d after traction; C: Lateral radiographs 12 d after traction, showing satisfactory closed reduction; D: Post-reductional parasagittal magnetic resonance imaging, demonstrating that the spinal cord was still compressed by C1 posterior arch.

Figure 3 Postoperative images during the 3-yr follow up. A: Lateral radiograph indicating stable fixation and fusion; B: Axial computed tomography scan, demonstrating the C1 inner sagittal diameter (white line) = 32.75 mm and the canal sagittal diameter (black line) = 22.24 mm; C: Parasagittal magnetic resonance imaging, demonstrating satisfactory release of compression caused by the odontoid process and C1 posterior arch.