Fig. 3
From: Risk factors of instrumentation failure after laminectomy and posterior cervical fusions (PCF)
Radiological evaluation of the cervical sagittal alignment parameters. (1) C2-C7 sagittal vertical axis (SVA); (2) T1 slope (T1S); (3) C2-C7 cervical lordosis (CL). The C2-C7 SVA was obtained through measuring the distance from the posterior-superior corner of C7 to a vertical line that bisected the C2 centroid. The T1 slope is the angle created from a line tangential to the superior end plate of T1 and a horizontal line. Lastly, the C2-C7 CL was measured using the Cobb angle between the inferior end plate of C2 to the inferior end plate of C7