Sequential sagittal alignment changes in the cervical spine after occipitocervical fusion

Figure 2 A 43-year-old woman developed dysphagia after occipitocervical fusion surgery. A: The preoperative O-C2 angle (O-C2a), C2-7 angle (C2-7a) and pharyngeal inlet angle (PIA) were 11.1°, 10.8°, and 93.8°, respectively; B: The OC2a and PIA decreased to -9.3° and 81.5°, respectively, while the C2-7a increased to 42.9° 1 mo postoperatively; C: At the 1-year follow-up, the O-C2a, C2-7a, and PIA were -8.9°, 38.2°, and 83.7°, respectively. O-C2a: O-C2 angle; C2-7a: C2-7 angle; PIA: Pharyngeal inlet angle.