Table 20 Results of different exercise types compared to control interventions for pain and disability. Yoga

Anheyer et al. (2021) [70]

AMSTAR-2

High

Pain:

ABPS, BPI, CPGS, DVPRS, NRS, NHP-P; PDI, VAS

Disability:

FFbHR, ODI, RMDQ, SF12/36

Follow-up

Short-term: Post-intervention and closest to 12 weeks after randomization

Long-term: closest to 6 months after randomization

Yoga > passive control group

Short-term (15 trials):

MD = -0.74 (95%CI -1.04; -0.44)

Long-term (10 trials):

MD = -0.58 (95%CI -0.94; -0.22)

Yoga = active control group

Short-term (10 trials):

MD = -0.78 (95%CI -1.62; 0.06)

Long-term (5 trials):

MD = -0.62 (95%CI -3.10; 1.86)

Yoga > passive control group

Short-term (15 trials):

MD = -2.28 (95%CI -3.30; -1.26)

Long-term (11 trials):

MD = -2.34 (95%CI -3.30; -1.38)

Yoga = active control group

Short-term (10 trials):

MD = -2.04 (95%CI -4.02; -0.06)

Long-term (5 trials):

MD = -0.24 (95%CI -1.74; 1.32)

Compared with passive control, yoga was associated with short-term improvements in pain intensity and pain-related disability. The effects were sustained in the long-term. However, no clinically relevant point estimates were observed

Compared with an active comparator, yoga was not associated with any significant differences in short-term or long-term outcomes.

Büssing et al. (2012) [71]

AMSTAR-2

High

Pain:

VAS, PPI

Disability:

ODI, RMDQ

Follow-up:

Post-intervention

Yoga > control (3 trials)

SMD = -1.06 (95%CI -1.06; -0.32)

Yoga > control (6 trials)

SMD = -0.76 (95%CI -1.08;-.43)

This meta-analysis suggests that yoga is a useful supplementary approach with moderate effect sizes on pain and associated disability. Looking at the studies with passive (waiting list) controls, the treatment effects with respect to pain were higher than those with an active control (i.e., physical activity), while with respect to disability, there were no relevant differences between the control groups.

Chang et al. (2016) [72]

AMSTAR-2

Low

Pain:

MPQ, VAS

Disability:

SF-12, SF-36, PDI, ODI, RMDQ

Follow-up:

Post-intervention

Other time points reported in only 4 studies and was not analyzed

Yoga > MI/usual care

Yoga = non-pharmacologic treatment

Yoga appears as effective as other non-pharmacologic treatments in reducing the functional disability of back pain. It appears to be more effective in reducing pain severity or “bothersomeness” of CLBP when compared to usual care or no care. Yoga may have a positive effect on depression and other psychological co-morbidities, with maintenance of serum BDNF and serotonin levels. Yoga appears to be an effective and safe intervention for chronic low back pain.

Cramer et al. (2013) [46]

AMSTAR-2

Moderate

Pain:

ABPS, MPQ, PPI,

NRS, VAS

Disability:

RMDQ, ODI

PDI

Follow-up:

Post- intervention

Short-term: closest to 12 wks after randomization

Long-term: closest to 12 mo after randomization

Yoga > control

Short-term:

SMD = -0.48 (95%CI -0.65; -0.31)

Long-term:

SMD = -0.33 (95% CI -0.59; -0.07)

Yoga was not associated with serious adverse events

Yoga > control

Short-term:

SMD = -0.59 (95%CI -.87; -0.30)

Long-term:

SMD = -0.35 (95% CI, -0.55; -0.15)

Strong evidence for short-term effectiveness and moderate evidence for long- term effectiveness of yoga for chronic LBP. Low number of adverse events. When comparing yoga to education, there was strong evidence for small short-term effects on pain and back-specific disability Yoga can be recommended as an additional therapy to patients who do not improve with education on self-care options.

Crow et al. (2015) [73]

AMSTAR-2

Low

Pain:

VAS, PPI, ABS

Disability:

PSEQ, RMDQ

Follow-up:

At post-intervention (2 trials)

Short-term: < 3 mo (4 trials)

Long-term: > 3 mo (3 trials)

Yoga > control

Post-intervention and short-term

56–69% decrease

Yoga = control

Long-term: NR

Yoga > control

Post-intervention and short-term

Lower RMDQ points

Yoga = control

Long-term: NR

This systematic review found strong evidence for short-term effectiveness, but low/moderate evidence for long-term effectiveness of yoga for chronic spine pain in the patient-centered outcomes.

Hill (2013) [74]

AMSTAR-2

Low

Pain:

NR

Disability:

ODI, RMDQ

Follow-up:

Short-term: post intervention 3 mo (3 trials), after 1 wk (1 trial)

Intermediate term: 6 mo (3 trials)

Long-term: 12 mo (1 trial)

Yoga > usual care

At 3, 6 and 12 mo no significance differences

Yoga > standard medical care or self-care book

At 3 and 6 mo significant improvement

Yoga > physical therapy program

At 1 wk significant improvement

Yoga > usual care

At 3, 6 and 12 mo significant improvement

Yoga > standard medical care or self-care book

At 3 and 6 mo significant improvement

Yoga > physical therapy program

At 1 wk significant improvement

Three out of the four papers conclude that yoga is an effective management tool for CLBP, with all four concluding that it is effective in improving back function.

Holzman et al. (2013) [75]

AMSTAR-2

Low

Pain:

VAS, NRS, Bothersomeness of pain (11-scale)

Disability:

ODI

Follow-up:

Short-term: post-intervention

Long-term: 12–24 wks

Yoga > control

Post-Treatment after Yoga (5 trials)

d = 0.623 (95%CI 0.377; 0.868)

Follow-up after Yoga (5 trials)

d = 0.397 (95%CI 0.053; 0.848)

Yoga > control

Post treatment after Yoga: (8 trials)

d = 0.645 (95%CI 0.496; 0.795)

Follow up after Yoga: (6 trials)

d = 0.486 (95%CI 0.226; 0.746)

Yoga may represent an efficacious adjunctive treatment for CLBP; the effect size for yoga in reducing pain and functional disability appears to be similar to, if not higher than, effects sizes for more traditional exercise therapy, cognitive behavioral therapy and acupuncture). Overall, the findings provide the strongest support for the effects of yoga on short-term improvements in functional disability among patients with CLBP; a range of different yoga interventions yielded statistically similar effect sizes.

Posadzki & Ernst (2011) [76]

AMSTAR-2

Low

Pain:

VAS, NRS, Pain medication usage, pain score not defined, pain-related attitudes/ behaviors

Disability:

ODI, RMDQ

Follow-up:

Post intervention: After 1, 6, 16, 24 wks (1 trial),

12 wks (3 trials)

Hatha Yoga, Iyenger yoga > usual care

Significant reduction (1 trial)

Viniyoga > Self-care book (1 trial)

Significant reduction

Viniyoga > conventional therapeutic exercise (1 trial)

Significant reduction

Iyenger yoga + usual care > educational control + usual care (1 trial)

Significant reduction

Yoga + written advice > usual care + written advice (1 trial)

Significant reduction

Hatha Yoga > usual care (1 trial)

No significant

Iyenger yoga > usual care (1 trial)

Significance reduction

Viniyoga > Self-care book (1 trial)

Significant reduction

Viniyoga > conventional therapeutic exercise (1 trial)

No significance

Iyenger yoga + usual care > educational control + usual care (1 trial)

Significant reduction

Yoga + written advice > usual care + written advice (1 trial)

No significant

Yoga asanas, pranayamas, medication and didactics > physical exercise (only evaluated disability) (1 trial)

Significant reduction

Iyenger yoga > no treatment (only evaluated disability) (1 trial)

No significance

It is concluded that yoga has the potential to alleviate low back pain. However, any definitive claims should be treated with caution.

Wieland et al. (2017) [19]

AMSTAR-2

High

Pain:

VAS

Disability:

RMDQ

Follow-up:

Short-term: 4–6 wks

Intermediate term: 10 wks-3 mo

Long-term: 6–12 mo

Yoga > non-exercise controls

Short-term: (2 trials)

MD = -10.83 (95% CI -20.85; -0.81)

Intermediate term: 3 mo (5 trials)

MD = -4.55 (95% CI -7.04; -2.06)

Long-term: 6 mo (4 trials)

MD = -7.81 (95% CI -13.37; -2.25)

Yoga = non-yoga exercise controls

Long-term: 12 mo (2 trials)

MD = -5.40 (95% CI -14.50; 3.70)

Yoga + exercise > exercise alone

Short-term: 4 wks (1 trial)

MD = -15.00 (95% CI -19.90; -10.10)

Long-term: 7 mo (1 trial)

MD = -20.40 (95% CI -25.48;-15.32)

Yoga > exercise and brief intensive residential (1 trial)

MD = -14.50 (95% CI -22.92; -6.08)

Yoga = as add on exercise intervention

Intermediate term: (1 trial)

MD -3.20 (95% CI -13.76; 7.36)

Yoga > non-exercise controls

Short-term: (5 trials)

SMD = ‐0.45 (95%CI ‐0.71; ‐0.19)

Intermediate term: 3 mo (7 trials)

SMD = ‐0.40 (95%CI ‐0.66; ‐0.14)

Long-term: 6 mo (6 trials)

SMD = ‐0.44 (95% CI ‐0.66; ‐0.22)

Long-term: 12 mo: (2 trials)

SMD = ‐0.26 (95%CI ‐0.46; ‐0.05)

Yoga + exercise = exercise alone

Short-term: (2 trials)

SMD = -0.02 (95% CI -0.41; 0.37)

Intermediate term: (2 trials)

SMD = -0.22 (95%CI -0.65; 0.20)

Long-term:

SMD = -0.20 (95%CI -0.59; 0.19)

Yoga > exercise and brief intensive residential (1 trial)

SMD = -1.25 (95% CI -1.73;-0.77)

Yoga = as add on exercise intervention

Intermediate term: (1 trial)

MD = -0.60 (95% CI -1.42; 0.22)

There is low- to moderate-certainty evidence that yoga compared to non-exercise controls results in small to moderate improvements in back-related function at three and six months

Yoga may also be slightly more effective for pain at three and six months, however the effect size did not meet predefined levels of minimum clinical importance

It is uncertain whether there is any difference between yoga and other exercise for back-related function or pain, or whether yoga added to exercise is more effective than exercise alone

Yoga is associated with more adverse events than non-exercise controls, but may have the same risk of adverse events as other back-focused exercise. Yoga is not associated with serious adverse events.

Zhu et al. (2020) [77]

AMSTAR-2

High

Pain:

VAS, NPRS, 0–10 bothersomeness of pain, ABPS, OBPI, BPI

Disability:

ODI, RMDQ

Follow-up:

Short-term: after 7 days intervention, 4–10 wks

Intermediate: 3mo and 6–7 mo

Long-term: 12 mo

Yoga > non-exercise control group (12 trials)

Short-term 4–8 wks:

MD = -0.83 (95%CI -1.19; -0.48)

Intermediate 3 mo:

MD = -0.43 (95%CI -0.64; -0.23)

Intermediate 6–7 mo:

MD = -0.56 (95%CI -1.02; -0.11)

Yoga = non-exercise control group

Long-term 12 mo (2 trials):

MD = -0.52 (95%CI -1.64; 0.59)

Yoga > physical therapy exercise (9 trials):

Short-term (1 wk):

MD = -2.36 (95%CI -3.15; -1.56)

Yoga = physical therapy exercise (9 trials):

Short-term (4–10 wks):

MD = -0.37 (95%CI -1.16; 0.42)

Intermediate (3 mo):

MD = 0.19 (95%CI -0.63; 1.01)

Intermediate (6 mo):

MD = -0.73 (95%CI -2.13; 0.67)

Yoga > non-exercise control group (11 trials):

Short-term 4–8 wks:

MD = -0.30 (95%CI -0.51; -0.10)

Intermediate 3 mo:

MD = -0.31 (95%CI -0.45; -0.18)

Intermediate 6 mo:

MD = -0.38 (95%CI -0.53; -0.23)

Yoga > non-exercise control group

Long-term 12 mo (2 trials):

MD = -0.33 (95%CI -0.54; -0.12)

Yoga = physical therapy exercise (6 trials):

Short-term (6 wks):

MD = -0.34 (95%CI -1.60; 0.92)

Intermediate (3 mo):

MD = -0.04 (95%CI -1.76; 1.67)

Intermediate (6 mo):

MD = -1.32 (95%CI -2.78; 0.13)

This meta-analysis provided evidence from very low to moderate investigating the effectiveness of yoga for chronic low back pain patients at different time points. Yoga might decrease pain from short term to intermediate term and improve functional disability status from short-term to long term compared with non-exercise (e.g. usual care, education). Yoga had the same effect on pain and disability as any other exercise or physical therapy.

Zou et al. (2019) [78]

AMSTAR-2

Moderate

Pain:

NRS, VAS, ABPS

Disability:

RMDQ, ODI

Follow-up:

Post intervention and after 1, 4, 6, 8, 16, 24 wks (1 trial)

12 wks (6 trials)

Yoga > all different control groups (7 trials)

SMD = -0.33 (95%CI -0.47; -0.19)

Yoga = all different control groups (10 trials)

No significant differences were observed

Yoga may be beneficial for reducing pain but not disability in CLBP symptomatic management, irrespective of non-control comparison or active control comparison (conventional exercises, core training, and physical therapy programs). Before definitive conclusions can be drawn, future work is needed that employs more robust study designs and implements long-term follow-up assessments