Lumbar facet injection for the treatment of chronic piriformis myofascial pain syndrome: 52 case studies

Figures & data

Table 1 Characteristics of the 52 patients who completed the 2-week study

	Male	Female	All subjects
Number of subjects	40	12	52
Age (years), mean ± SD	54.0±10.4	59.0±6.4	52.3±9.7
Side  Right, n	20	7	27
Left, n	20	5	25
With low back pain, n	29	7	36
With ipsilateral sciatica, n	11	3	14
With ipsilateral weakness, n	2	0	2
With ipsilateral sensory deficit, n	5	2	7
With reduced tendon reflex, n	9	1	10

Abbreviation: SD, standard deviation.

Table 2 Characteristics of 36 patients who completed the follow-up assessment 6 months after the injection

	Male	Female	All subjects
Number of subjects	28	8	36
Age (years), mean ± SD	54.3±10.8	57.0±6.6	51.4±9.9
Side  Right, n	14	5	19
Left, n	14	3	17
With low back pain, n	21	4	25
With ipsilateral sciatica, n	9	2	11
With ipsilateral weakness, n	1	0	1
With ipsilateral sensory deficit, n	4	2	6
With reduced tendon reflex, n	8	1	9

Abbreviation: SD, standard deviation.

Table 3 Changes in pain intensity after facet joint injection

	Before injection (n=52)	Immediately after injection (n=52)	2 weeks after injection (n=52)	6 months after injection (n=36)
Number (%) of patients with
Pain intensity 0/10	0 (0%)	27 (51.9%)	27 (51.9%)	22 (61.1%)
Pain intensity 1/10 to 5/10	0 (0%)	19 (36.5%)	22 (42.3%)	13 (36.1%)
Pain intensity 6/10 to 9/10	52 (100%)	6 (11.5%)	3 (5.8%)	1 (2.8%)

Table 4 Assessments before, immediately after, 2 weeks after, and 6 months after injection

	Before injection (n=52)	Immediately after injection (n=52)	2 weeks after injection (n=52)	6 months after injection (n=36)
Pain intensity, mean ± SD	7.4±0.9	1.6±2.1*,a	1.3±2.0*,a	0.9±1.5*,a
Range of trunk extension, mean ± SD (degrees)	13.4±6.8 (n=52)	22.1±6.0*,a (n=52)	26.5±5.6**,a (n=52)	28.6±4.6**,a (n=36)
Lumbar facet sign
Positive, n (%)	52 (100%)	7 (13.5%)*,b	5 (9.6%)*,b	2 (5.6%)*,b
Negative, n (%)	0 (0%)	45 (86.5%)	47 (90.4%)	34 (94.4%)

Note:

* P<0.01 compared with result before the injection and

** P<0.01 compared with result immediately after the injection. Statistical tests used:

a repeated measures one-way analysis of variance and

b chi-square test.

Abbreviation: SD, standard deviation.