Table 2:

Number of injections performed by year in the literature and our data with complications, number, and rate^a

Year	Transforaminal Injections	Patients	CIRSE Grade 1	CIRSE Grade 2	CIRSE Grade 3	Overall Adverse Event Rate
2018	36	16	2	0	0	5.6%
2019	69	16	1	0	0	1.4%
2020	451	74	31	2	3	6.9%
Total	556	106	34	2	3	7%
Adverse event rate			5.8%	0.3%	0.5%
Institutional experience	42	8	1	0	0	2.4%

^aData include the total adverse event rate categorized by CIRSE grade as well as by year.