Table 1. Details of previously reported LMS fixation techniques.

Technique	Year	Entry point	Lateral angulation	Sagittal angulation
Roy-Camille3)	1989	Midpoint of the LM	10° lateral	90° to the LM surface
Louis7)	1991	At the intersection of a vertical line 5 mm medial to the lateral edge of the facet joint and a horizontal line 3 mm below the inferior edge of the facet joint line above	Straight ahead, no lateral angulation	90° to the LM surface
Magerl6)	1991	1 mm medial and 1 mm cranial to the midpoint of the LM	20–30° lateral	Parallel to the adjacent facet joints
Anderson5)	1991	1 mm medial to the midpoint of the LM	10° lateral	30–40° in a cephalad direction (also parallel to the facet joint)
An4)	1991	1 mm medial to the midpoint of the LM	30° lateral	15° of cephalad angulation
Kim8)	2012	1 mm medial to the midpoint of the LM	24–30° lateral	Parallel to the angle of the spinous process
Riew1)	2018	1 mm medial and 1 mm caudal to the midpoint of the LM	Aim toward the upper and outer corner of the LM	Aim toward the upper and outer corner of the LM
Rathinavelu9)	2020	2 mm lateral to the medial border of the LM and 2 mm above the inferior facet joint	Aim toward the upper and outer corner of the LM	Aim toward the upper and outer corner of the LM

LM: lateral mass, LMS: lateral mass screw.