Table 2.

Comparison of cervical sagittal parameters

	Low SCA (n = 34)	High SCA (n = 15)	p value
SCA (°)
Pre	76.00 ± 6.20	93.85 ± 4.90	< 0.001
Post	73.46 ± 7.91	87.78 ± 3.90	< 0.001
F/U 2y	72.61 ± 7.25	86.73 ± 4.23	< 0.001
△SCA (°)(pre vs post)	− 2.54 ± 5.59	− 6.07 ± 3.49	0.036
△SCA (°)(pre vs F/U)	− 3.39 ± 5.68	− 7.11 ± 3.19	0.022
Pre vs F/U	< 0.001	< 0.001
T1s (°)
Pre	30.75 ± 6.42	24.85 ± 3.17	< 0.001
Post	31.29 ± 6.14	26.12 ± 4.01	0.001
F/U 2y	31.25 ± 6.48	26.07 ± 3.30	0.001
△T1s (°)(pre vs post)	0.54 ± 3.52	1.27 ± 2.37	0.704
△T1s (°)(pre vs F/U)	0.50 ± 3.80	1.23 ± 2.37	0.499
Pre vs F/U	0.448	0.065
CA (°)
Preoperative	18.29 ± 7.09	9.87 ± 4.90	< 0.001
Post	21.64 ± 8.30	16.05 ± 4.23	0.003
F/U 2y	23.21 ± 8.16	18.35 ± 3.91	0.007
△CA (°)(pre vs post)	3.34 ± 4.83	6.18 ± 5.62	0.078
△CA (°)(pre vs F/U)	4.91 ± 5.60	8.48 ± 4.77	0.037
Pre vs F/U	< 0.001	< 0.001
cSVA (mm)
Pre	17.44 ± 5.56	21.15 ± 7.61	0.104
Post	24.50 ± 7.21	30.06 ± 6.03	0.012
F/U 2y	26.79 ± 13.38	27.87 ± 8.43	0.565
△cSVA (mm) (pre vs post)	7.06 ± 6.00	8.91 ± 6.45	0.448
△cSVA (mm) (pre vs F/U)	9.35 ± 14.18	6.72 ± 7.29	0.397
Pre vs F/U	< 0.001	< 0.001
T1sCA (°)
Pre	12.46 ± 5.52	14.97 ± 7.06	0.329
Post	9.65 ± 6.27	10.07 ± 5.66	0.826
F/U 2y	8.05 ± 6.27	7.72 ± 5.60	0.863
△T1sCA (°) (pre vs post)	− 2.81 ± 5.48	− 4.91 ± 6.74	0.256
△T1sCA (°) (pre vs F/U)	− 4.41 ± 6.13	− 7.25 ± 6.09	0.141
Pre vs F/U	< 0.001	< 0.001

SCA spino cranial angle, T1s T1-Slope, CA C2–7 lordosis angle, cSVA C2–7 sagittal vertical axis, T1sCA T1s minus CA