Table 2.

Estimated skeletal maturation level within each volume level of the second, third, and fourth cervical vertebrae.

Volumes (mm3)		1000	1500	2000	2500	3000	3500	R-square
2nd vertebra (C2) (quadratic regression model)	Female	33.994	52.632	69.358	84.170	97.070	100>	0.6047
	Male	26.803	28.076	37.237	54.285	79.220	100>
	Diff.	7.191	24.556	32.121	29.886	17.850	—
	P value	0.349	<0.0001	<0.0001	<0.0001	0.121	—
3rd vertebra (C3) (linear regression model including sex-related interaction)	Female	34.387	50.041	65.695	81.349	97.004	100>	0.8129
	Male	16.485	28.715	40.945	53.176	65.406	77.636
	Diff.	17.903	21.327	24.750	28.174	31.598	35.021
	P value	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001
4th vertebra (C4) (linear regression model)	Female	35.761	48.527	61.292	74.057	86.823	99.588	0.8176
	Male	13.751	26.517	39.282	52.047	64.812	77.578
	Diff.	22.010	22.010	22.010	22.010	22.010	22.010
	P value	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001