The Influence of Natural Head Position on the Cervical Sagittal Alignment

Table 3

ANOVA test for comparison of each radiographic parameter among four head positions.

Variable	Head position
	FE	BE	FF	BF
C0–C2 angle	19.38 ± 8.05	16.38 ± 6.50	12.86 ± 4.92★	6.85 ± 5.09★	0.001
C2–C5 angle	1.13 ± 7.78	4.51 ± 7.97	2.51 ± 6.56	0.88 ± 5.19	0.227
C5–C7 angle	3.23 ± 6.05	6.39 ± 6.76	0.75 ± 5.62▲	7.15 ± 6.33	0.013
C2–C7 angle	4.36 ± 8.09	10.90 ± 9.82★	3.26 ± 8.61▲	8.03 ± 9.66	0.004
T1 slope	23.67 ± 6.02	23.10 ± 7.62	23.54 ± 5.29	21.70 ± 5.06	0.940
C0–C2 SVA	4.74 ± 5.47	−3.40 ± 4.74★	8.41 ± 4.75▲	2.65 ± 3.78	<0.001
C2–C7 SVA	22.21 ± 5.32	12.71 ± 6.39★	26.93 ± 8.98▲	9.10 ± 3.12★■	<0.001

Note: ★ indicates in comparison with the FE group; ▲ indicates in comparison with the BE group; ■ indicates in comparison with the FF group.