Table 1.

Key characteristics of RCTs included in the meta-analysis

Studies	Type	Study period	Sample size		Mean age (mean)		Gender (F/M)		Disease
									Flexion			Extension
			Flexion	Extension	Flexion	Extension	Flexion	Extension	OA	RA	PO	OA	RA	PO
Ong 2003 [42]	RCT	2000	20	20	71	74	12/8	13/7	20	0	0	20	0	0
Ma 2008 [27]	RCT	2005–2006	49	46	71	70.6	25/24	22/24	46	3	0	42	4	0
Li 2017 [24]	RCT	2011–2012	54	54	72.6	71.7	43/11	46/8	47	7	0	44	10	0
Liu 2015 [22]	RCT	2013–2014	50	50	73.1	72.4	34/16	32/18	50	0	0	50	0	0
Zeng 2018 [26]	RCT	2016–2017	30	30	68.78	69.68	21/9	20/10	NA	NA	0	NA	NA	0
Panni 2014 [25]	RCT	2012–2013	50	50	69	61	38/12	40/10	50	0	0	50	0	0
Yang 2015 [23]	RCT	2012–2014	23	23	73.6	72.5	11/12	10/13	23	0	0	23	0	0
Antinolfi 2014 [28]	RCT	NA	20	20	73	70.7	13/7	10/10	20	0	0	20	0	0
Napier 2014 I [20]	RCT	2003–2004	86	89	70.4	71	64/22	58/32	78	5	3	78	6	5
Napier 2014 II [20]	RCT	2006	134	140	68.9	70.9	83/51	101/39	131	3	0	137	3	0
Li 2012 [21]	RCT	2008	55	55	71	70	40/15	38/17	47	8	0	46	9	0
Zhao 2014 [36]	RCT	2011–2013	111	102	64.2	63.2	111/0	102/0	111	0	0	102	0	0
Shen 2016 [38]	RCT	2013–2016	90	90	61.9	62.3	54/36	53/37	90	0	0	90	0	0
Hu 2013 [35]	RCT	2010–2012	65	68	67.7	67.8	65/0	68/0	65	0	0	68	0	0
Li 2016 [39]	RCT	2015	50	50	63.1	62.4	16/34	18/32	50	0	0	50	0	0
Guo 2013 [37]	RCT	2012	30	30	72	71	23/7	22/8	30	0	0	30	0	0
Peng 2016 I [34]	RCT	2014–2015	30	30	73.5	73.0	18/12	19/11	30	0	0	30	0	0
Peng 2016 II [34]	RCT	2014–2015	30	30	74.1	73.0	17/13	19/11	30	0	0	30	0	0

Abbreviations: OA osteoarthritis, RA rheumatoid arthritis, PO patellofemoral osteoarthritis, NA not available