Table 3.

Main results of the meta-analysis

Indicators	$n$	MD	SMD	95% CI		$P$ value	I${}^2$ (%)	$P$ for heterogeneity	Model	$P$ for publication bias
Average operation time	10	4.12	NA	$-$11.64	$\sim$ 19.87	0.609	97.7	0.000	REM	0.863
Intraoperative bleeding volume	11	$-$133.82	NA	$-$167.10	$\sim$$-$100.53	0.000	99.2	0.000	REM	0.724
Postoperative drainage	7	$-$114.43	NA	$-$141.12	$\sim$$-$87.74	0.000	99.1	0.000	REM	0.122
Postoperative landing time	4	$-$3.30	NA	$-$4.31	$\sim$$-$2.28	0.000	93.5	0.000	REM	0.625
Postoperative back VAS	6	NA	$-$1.44	$-$2.63	$\sim$$-$0.34	0.010	96.4	0.000	REM	0.591
Postoperative leg VAS	4	NA	0.00	$-$0.36	$\sim$ 0.36	0.998	64.5	0.000	REM	0.098
Postoperative ODI	7	NA	$-$0.59	$-$1.22	$\sim$ 0.03	0.063	94.2	0.000	REM	0.935
Postoperative JOA	3	NA	0.41	0.15	$\sim$ 0.66	0.002	13.1	0.316	FEM	0.707

MD: Mean difference; SMD: Standard mean difference; CI: Confidence internal; REM: Random effect model; FEM: Fixed effect model.