Table 2

Comparison of outcome data through 12-month follow-up

Outcome variable	RFA group (N=32)	Sham RF group (N=32)	P value	Mean difference from baseline		P value
Outcome variable	RFA group (N=32)	Sham RF group (N=32)	P value	RFA group	Sham RF group	P value
VAS pain score (mean, SD)
Baseline	5.7±1.9 (n=32)	5.0±1.4 (n=32)	0.13
1 month	3.0±2.3 (n=32)*	3.1±1.9 (n=32)*	0.64	2.7±2.3	1.9±2.2	0.15
2 months	3.1±2.3 (n=32)*	3.3±2.4 (n=30)*	0.82	2.6±2.9	1.6±2.6	0.82
4 months	3.1±2.3 (n=31)*	3.7±2.7 (n=30)*	0.38	2.5±2.5	1.1±2.7	0.04
6 months	3.3±2.7 (n=29)*	3.1±2.3 (n=30)*	0.93	2.4±2.7	1.7±2.7	0.29
8 months	3.5±2.5 (n=28)*	3.3±2.3 (n=28)*	0.75	2.1±2.7	1.5±2.4	0.36
10 months	3.4±2.6 (n=26)*	3.4±2.5 (n=27)*	0.99	2.1±2.5	1.4±2.5	0.36
12 months	3.2±2.6 (n=26)*	2.6±2.4 (n=27)*	0.40	2.3±2.8	2.2±2.4	0.73
WOMAC (mean, SD)
Baseline
Overall	91.2±38.2 (n=32)	95.8±41.2 (n=32)	0.35
Pain	20.4±7.7 (n=32)	20.6±8.0 (n=32)	0.95
Stiffness	8.2±3.8 (n=32)	8.5±3.9 (n=32)	0.72
Function	62.4±27.0 (n=32)	66.7±30.5 (n=32)	0.55
1 month
Overall	63.6±51.8 (n=32)*	66.8±42.4 (n=32)*	0.45	26.6±37.7	27.2±37.7	0.78
Pain	13.7±10.3 (n=32)*		0.90	6.8±7.6	6.6±9.8	0.93
Stiffness	5.7±4.4 (n=32)*	14.0±9.0 (n=32)*	0.87	2.5±3.4	3.0±4.5	0.60
Function	41.9±36.6 (n=32)*	5.5±4.6 (n=32)*	0.58	20.5±27.3	20.2±26.7	0.97
2 months		46.5±29.1 (n=32)*
Overall	71.5±48.4 (n=32)*	63.5±42.2 (n=30)*	0.51	20.7±40.9	26.6±46.4	0.72
Pain	15.1±11.7 (n=32)*	13.5±9.0 (n=30)*	0.56	5.3±10.0	6.3±9.7	0.69
Stiffness	5.7±4.1 (n=32)*	5.5±4.1 (n=30)*	0.88	2.5±4.0	2.7±5.1	0.89
Function	47.5±35.9 (n=32)*	44.0±30.8 (n=30)*	0.68	14.8±26.9	21.1±35.4	0.44
4 months
Overall	68.2±46.3 (n=31)	75.9±45.1 (n=30)*	0.49	19.8±42.9	21.9±41.2	0.95
Pain	13.7±10.0 (n=31)*	16.2±9.3 (n=30)*	0.32	6.9±9.2	3.6±7.3	0.17
Stiffness	5.7±4.1 (n=31)*	6.3±4.7 (n=30)*	0.60	2.5±4.3	1.9±4.6	0.63
Function	46.7±33.7 (n=31)*	51.4±31.7 (n=30)*	0.58	15.3±28.7	13.7±29.4	0.83
6 months
Overall	76.0±64.0 (n=29)	72.7±50.2 (n=30)*	0.99	27.1±42.7	34.7±54.4	0.81
Pain	15.0±12.8 (n=29)*	15.1±10.8 (n=30)*	0.97	5.3±10.7	4.8±11.1	0.84
Stiffness	5.7±5.8 (n=29)*	5.9±4.6 (n=30)*	0.88	2.5±5.1	2.3±5.0	0.87
Function	47.6±40.2 (n=29)*	48.9±35.4 (n=30)*	0.90	15.2±29.5	16.2±35.7	0.91
8 months
Overall	74.6±50.3 (n=28)	66.2±43.5 (n=28)*	0.49	15.0±42.9	23.5±46.2	0.47
Pain	16.3±11.4 (n=28)	16.0±11.0 (n=28)	0.93	3.9±9.6	3.3±10.2	0.82
Stiffness	6.6±5.2 (n=28)	4.9±4.3 (n=28)*	0.19	1.7±4.6	3.1±4.8	0.26
Function	50.0±35.1 (n=28)	47.1±29.5 (n=28)*	0.74	12.6±33.3	14.3±33.4	0.85
10 months
Overall	67.4±43.5 (n=26)	70.5±45.1 (n=27)	0.84	17.3±42.0	16.8±41.0	0.99
Pain	14.5±10.6 (n=26)	15.1±10.4 (n=27)	0.84	4.2±10.0	3.9±10.0	0.90
Stiffness	6.0±4.6 (n=26)	5.3±4.3 (n=27) *	0.57	1.7±4.5	2.7±5.3	0.43
Function	45.1±29.7 (n=26)	49.1±30.6 (n=27)	0.64	13.2±30.3	11.4±29.6	0.82
12 months
Overall	67.1±51.9 (n=26)	60.6±42.82 (n=27)*	0.85	17.7±49.2	24.6±38.5	0.70
Pain	13.2±10.0 (n=26)*	13.9±10.0 (n=27)*	0.79	5.6±9.6	5.1±9.3	0.85
Stiffness	6.2±5.4 (n=26)	4.6±4.1 (n=27)*	0.21	1.4±5.5	3.5±4.2	0.13
Function	45.9±37.3 (n=26)	42.2±28.4 (n=27)*	0.69	12.5±37.7	18.2±27.5	0.53
PGI-I (mean, SD)
1 month	2.3±0.8 (n=32)	2.5±0.8 (n=32)	0.65
2 months	2.6±1.0 (n=32)	2.5±1.1 (n=30)	0.92
4 months	2.5±0.9 (n=31)	2.7±1.1 (n=30)	0.28
6 months	2.6±1.0 (n=29)	2.4±0.9 (n=30)	0.46
8 months	2.9±1.3 (n=28)	2.8±1.3 (n=28)	0.69
10 months	2.9±1.1 (n=26)	3.0±1.4 (n=27)	0.74
12 months	2.8±1.3 (n=26)	2.6±1.3 (n=27)	0.56

Overall WOMAC score demostrated in bold.
*p<0.05 (comparing within the group; between baseline and different time point), overall WOMAC score may slightly deviate from the sum of the subscales due to variations in scoring.51
PGI-I, Patient Global Improvement-Index; RF, radiofrequency; RFA, RF ablation; VAS, Visual Analog Scale; WOMAC, Western Ontario and McMaster Universities Arthritis Index.