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Table 1: Group comparisons between patients receiving CT-guided spinal injections in 2009 and 2010^a
Patient Group 2009 2010 T Test P Value
Age (yr) 55.6 ± 14.0 59.9 ± 14.0 .128
Male 42% (21) 58% (29) NA
Injection sites 2.0 ± 1.0 (100) 2.1 ± 1.3 (103) .667
    Medial branch blocks 0.1 ± 0.3 (4) 0.1 ± 0.4 (4) 1.000
    Facet joint blocks 0.4 ± 0.8 (22) 0.6 ± 1.3 (28) .357
    Selective root blocks 1.3 ± 0.9 (63) 1.0 ± 1.0 (49) .118
    Epidural blocks 0.2 ± 0.4 (11) 0.4 ± 0.6 (22) .053
Injection levels 1.5 ± 0.7 (77) 1.6 ± 1.1 (81) .589
    Cervical levels 0.7 ± 0.8 (35) 0.2 ± 0.6 (12) .001
    Thoracic levels 0.1 ± 0.5 (5) 0.1 ± 0.3 (4) 1.000
    Lumbar levels 0.6 ± 0.8 (30) 1.1 ± 1.2 (53) .016
    Sacral levels 0.1 ± 0.4 (7) 0.2 ± 0.6 (12) .329
Hardware present 24% (12) 14% (7) NA
Reported pain^b 6.2 ± 1.8 (28) 6.3 ± 2.3 (36) .809
Immediate pain decrease 3.9 ± 2.4 4.4 ± 2.6 .320
Procedure time (min) 45.4 ± 19.1 43.1 ± 17.8 .535

↵a Fifty patients per group (mean ± SD) (total).

↵b The parentheses for this row indicate the number of patients with available data.

Patient Group	2009	2010	T Test P Value
Age (yr)	55.6 ± 14.0	59.9 ± 14.0	.128
Male	42% (21)	58% (29)	NA
Injection sites	2.0 ± 1.0 (100)	2.1 ± 1.3 (103)	.667
Medial branch blocks	0.1 ± 0.3 (4)	0.1 ± 0.4 (4)	1.000
Facet joint blocks	0.4 ± 0.8 (22)	0.6 ± 1.3 (28)	.357
Selective root blocks	1.3 ± 0.9 (63)	1.0 ± 1.0 (49)	.118
Epidural blocks	0.2 ± 0.4 (11)	0.4 ± 0.6 (22)	.053
Injection levels	1.5 ± 0.7 (77)	1.6 ± 1.1 (81)	.589
Cervical levels	0.7 ± 0.8 (35)	0.2 ± 0.6 (12)	.001
Thoracic levels	0.1 ± 0.5 (5)	0.1 ± 0.3 (4)	1.000
Lumbar levels	0.6 ± 0.8 (30)	1.1 ± 1.2 (53)	.016
Sacral levels	0.1 ± 0.4 (7)	0.2 ± 0.6 (12)	.329
Hardware present	24% (12)	14% (7)	NA
Reported pain^b	6.2 ± 1.8 (28)	6.3 ± 2.3 (36)	.809
Immediate pain decrease	3.9 ± 2.4	4.4 ± 2.6	.320
Procedure time (min)	45.4 ± 19.1	43.1 ± 17.8	.535