Table 1.

Characteristics of included studies.

Author	Publication year	Mean age	Male/female	Follow-up (mo)	Type of study design	Sample size	MINOR score	Level of evidence	Grade of recommendation
Ruetten et al	2008	43.0	68/132	24.0	Prospective	200	20	II	B
Kim et al	2015	48.3	15/7	24.0	Retrospective	44	17	III	C
Oertel et al	2016	55.3	27/16	28.8	Retrospective	43	11	III	B
Chen et al	2017	49.5	17/6	23.5	Retrospective	23	13	III	B
Park et al	2017	47.1	5/8	14.8	Retrospective	13	10	III	C
Youn et al	2017	56.2	13/9	24.0	Retrospective	22	10	III	C
Lee et al	2018	49.2	68/38	22.4	Retrospective	106	10	III	B
Wan et al	2018	38.0	14/11	12.0	Prospective	25	15	II	B
Shu et al	2019	63.0	14/18	12.0	Retrospective	32	10	III	B