TABLE 1. Demographic characteristics of 5 patients who underwent free hand placement of a C1 pedicle screw with direct visualization of the pedicle and serial dilatation technique.

Case	Sex	Age (years)	Diagnosis	Operative level	Operative time (min)	Blood loss (mL)
1	F	49	Os odontoideum	C1–2	249	100
2	M	54	C1–2 subluxation	C1–2	200	100
3	F	54	Os odontoideum	C1–2	180	200
4	F	76	C1–2 subluxation	C1–2	241	100
5	F	62	Os odontoideum	C1–2	191	100

F: female, M: male.