Fig. 1.

C-spine lateral film showing postoperative state of patient who underwent 3 level cervical arthroplasty for radiculopathy due to muli-level disc herniation. Implant level was measured by shell angles (A), and the adjacent levels were measured by disc space angles, measured on endplates. The functional spine unit (B) and overall cervical (C2-7) alignment (C) were measured by Cobb's method.