Accuracy Assessment of Using Rapid Prototyping Drill Templates for Atlantoaxial Screw Placement: A Cadaver Study

Table 1

Comparison of screw placement accuracy between the conventional method and RPDT navigation groups (Mann–Whitney test).

Grade	C1-LMS (axial plane)		C1-LMS (sagittal plane)		C2-PS
	Conventional method	RPDT navigation	Conventional method	RPDT navigation	Conventional method	RPDT navigation
1	16 (72.7%)	23 (95.8%)	20 (90.1%)	24 (100%)	16 (72.7%)	23 (95.8%)
2	4 (18.1%)	1 (4.2%)	2 (9.9%)	0 (0%)	4 (18.3%)	1 (4.2%)
3	2 (9.2%)	0 (0%)	0 (0%)	0 (0%)	1 (4.5%)	0 (0%)
4	—	—	—	—	1 (4.5%)	0 (0%)
Total	22	24	22	24	22	24
value	2.185		1.494		2.185
value	0.029		0.135		0.029