Table 1

Summary of randomized clinical trials of t'ai chi for osteoarthritis (OA)

First author (year), country	Sample size OA site, age (years), duration of OA (years)	Experimental intervention (regimen)	Control intervention (regimen)	Main outcomes	Adverse effects	Author's conclusion
Ni (2010), China11	35 Knee 62.9; 63.5 ≥1	TC (30 min, 2–4 times weekly for 24 weeks, n=18) Yang-style (simplified 24 forms)	Attention control programme (45 min, wellness and stretching, n=17)	(1) Pain (WOMAC) (2) Physical function (WOMAC) (3) Joint stiffness (WOMAC) (4) Total WOMAC score	No serious AE minor muscle soreness, pain in foot and knee (n=5)	‘[…] TC provides safe, feasible and useful exercise option for Chinese female patients with knee OA’
Brismee (2007), USA12	41 Knee 70.8; 68.8 NR	TC (40 min, 3 times weekly for 6 weeks plus home-based t'ai chi for 6 weeks, n=22) Yang-style (simplified 24 forms)	Attention control programme (40 min, lecture, once weekly for 6 weeks, n=19)	(1) Pain (VAS) (2) Physical function (WOMAC) (3) Joint stiffness (WOMAC)	Minor muscle soreness, pain in foot and knee (NR)	‘[…] TC […] provided significant knee pain reduction and physical function improvement in elderly subjects with knee OA’
Wang (2009), USA13	40 Knee 63; 68 NR	TC (60 min, twice weekly for 12 weeks, n=20) Yang-style (10 forms)	Attention control programme (60 min, wellness and stretching, once weekly for 12 weeks, n=20)	(1) Pain (WOMAC) (2) Physical function (WOMAC) (3) Joint stiffness (WOMAC) (4) Quality of Life (SF-36)	Increased knee pain (TC: 1); cancer (TC: 1; control: 1)	‘TC reduces pain and improves physical function […]’
Lee (2009), Korea14	44 Knee 70.2; 66.9 NR	TC (60 min, twice weekly for 8 weeks, n=29) NR (18 movements)	Waiting list (n=15)	(1) Pain (WOMAC) (2) Physical function (WOMAC) (3) Joint stiffness (WOMAC) (4) Total WOMAC score (5) Quality of Life (SF-36)	NR	‘TC appears to have beneficial effects […]’
Song (2003), Korea15	72 Knee 64.8; 62.5 10.4; 9.2	TC (60 min, 3 times weekly for 12 weeks, n=22) Sun-style (12 forms)	Routine care (n=21)	(1) Pain (WOMAC) (2) Physical function (ADL) (3) Joint stiffness (WOMAC)	NR	‘[…] TC […] was effective in improving […]’
Song (2009), Korea16	82 Knee 62.4; 59.9 0.5–10	TC [(60 min, twice weekly for the first 3 weeks and once weekly for the next 6 months) plus 6 instances of self-help programme, n=41] Sun-style (31 forms)	Self-help programme (2 h, once monthly for 6 months, n=39)	(1) Pain (WOMAC) (2) Physical function (WOMAC) (3) Joint stiffness (WOMAC)	NR	‘TC combined with self-help programme was more effective than the self-help only programme […]’
Fransen (2007), Australia17	152 Hip or knee 70.8; 70.0; 69.6 NR (mean)	(A) TC (60 min, twice weekly for 12 weeks, n=56) Sun-style (modified 24 forms)	(B) Hydrotherapy (60 min, twice weekly for 12 weeks, n=55) (C) Waiting list (n=41)	(1) Pain (WOMAC) (2) Physical function (WOMAC) (3) Quality of Life (SF-12)	11 serious AE that are not related to intervention. Low-back pain (hydrotherapy: 1; TC: 1)	‘[…] TC […] can provide large and sustained improvement in physical function […]’
Hartman (2000), USA18	35 Multiple joint (hip, knee, ankles, foot) 68.6; 67.5 NR (mean)	TC (60 min, twice weekly for 12 weeks, n=19) Yang-style (nine forms)	Routine care (usual physical activity plus total of three group meetings and telephone discussion every 2 weeks, n=16)	(1) Pain (AIMS) (2) Quality of life (AIMS)	NR	‘TC is a safe and effective […]’
Adler (2007), USA19	22 Hip or knee 70.8; 72.8 NR	TC (60 min, once weekly for 10 weeks, n=11) Wu-style (16 forms)	Bingo games (non-physical activity, n=11)	(1) Pain (WOMAC) (2) Physical function (ADL) (3) Psychological symptoms	NR	‘The current study will serve as a feasibility study for future TC research’

ADL, Activities of Daily Living; AE, adverse effects; AIMS, Arthritis Impact Measurement Scale; ITT, intention-to-treat; NR, not reported; NS, not significant; TC, t'ai chi; VAS, visual analogue scale; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.