Learning curves of robot-assisted pedicle screw fixations based on the cumulative sum test

Table 1 Comparison of the two stages in Surgeon A’s learning curve

Variables	Early stage	Late stage	P value
Number of surgeries	18	27
Number of screws	72	108
Screw accuracy	87.50%	96.30%	0.026
Operation time (min)	150 (128, 188)	120 (105, 150)	0.002
Blood loss (mL)	100 (88, 200)	100 (80, 100)	0.186

Table 2 Comparison of the two stages in Surgeon B’s learning curve

Variables	Early stage	Late stage	P value
Number of surgeries	17	13
Number of screws	68	52
Screw accuracy	91.18%	96.15%	0.475
Operation time (min)	177.35 ± 28.18	150.00 ± 34.64	0.024
Blood loss (mL)	200 (100, 200)	100 (100, 200)	0.095