Radiographic analysis of the sacral-2-alar screw trajectory

Table 2 Comparison of parameters between males and females

	Male (n = 48)	Female (n = 52)	P
Length of the screw trajectory (left) (mm)	47.18 ± 3.91	44.80 ± 3.66	0.002
Length of the screw trajectory (right) (mm)	45.46 ± 4.37	44.01 ± 3.72	0.075
Sagittal angle (left) (°)	29.06 ± 4.00	32.14 ± 5.48	0.002
Sagittal angle (right) (°)	23.33 ± 4.26	25.12 ± 5.19	0.065
Coronal angle (left) (°)	13.31 ± 6.95	16.04 ± 7.74	0.068
Coronal angle (right) (°)	14.88 ± 6.84	16.67 ± 8.34	0.244
Distance between the entry point and the spinous process (left) (mm)	21.0 (3.7)^a	21.8 (2.8)^a	0.423^b
Distance between the entry point and the spinous process (right) (mm)	22.8 (2.9)^a	21.6 (2.7)^a	0.143^b
Minimum diameter of the screw trajectory (left) (mm)	17.1 (2.3)^a	17.1 (5)^a	0.492^b
Minimum diameter of the screw trajectory (right) (mm)	16.82 ± 2.66	16.54 ± 3.55	0.656

The Shapiro–Wilk test showed that the length of the nail track, the angle of the sagittal plane, the angle of the coronal plane, and the right side of the minimum diameter of the nail track were normally distributed (P > 0.05); the distance between the nail entry point and the spinous process and the minimum diameter of the nail path had a non-normal distribution
^athe median (interquartile interval), ^bthe Mann–Whitney U test

ISSN: 1749-799X