BACKGROUND: Knee osteoarthritis (OA) is a major public health issue causing chronic pain, impaired physical function, and reduced quality of life. As there is no cure, self-management of symptoms via exercise is recommended by all current international clinical guidelines. This review updates one published in 2015.
OBJECTIVES: We aimed to assess the effects of land-based exercise for people with knee osteoarthritis (OA) by comparing: 1) exercise versus attention control or placebo; 2) exercise versus no treatment, usual care, or limited education; 3) exercise added to another co-intervention versus the co-intervention alone.
SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and two trial registries (ClinicalTrials.gov and World Health Organisation International Clinical Trials Registry Platform), together with reference lists, from the date of the last search (1st May 2013) until 4 January 2024, unrestricted by language.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) that evaluated exercise for knee OA versus a comparator listed above. Our outcomes of interest were pain severity, physical function, quality of life, participant-reported treatment success, adverse events, and study withdrawals.
DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane for systematic reviews of interventions.
MAIN RESULTS: We included 139 trials (12,468 participants): 30 (3065 participants) compared exercise to attention control or placebo; 60 (4834 participants) compared exercise with usual care, no intervention or limited education; and 49 (4569 participants) evaluated exercise added to another intervention (e.g. weight loss diet, physical therapy, detailed education) versus that intervention alone. Interventions varied substantially in duration, ranging from 2 to 104 weeks. Most of the trials were at unclear or high risk of bias, in particular, performance bias (94% of trials), detection bias (94%), selective reporting bias (68%), selection bias (57%), and attrition bias (48%). Exercise versus attention control/placebo Compared with attention control/placebo, low-certainty evidence indicates exercise may result in a slight improvement in pain immediately post-intervention (mean 8.70 points better (on a scale of 0 to 100), 95% confidence interval (CI) 5.70 to 11.70; 28 studies, 2873 participants). Moderate-certainty evidence indicates exercise likely results in an improvement in physical function (mean 11.27 points better (on a scale of 0 to 100), 95% CI 7.64 to 15.09; 24 studies, 2536 participants), but little to no improvement in quality of life (mean 6.06 points better (on a scale of 0 to 100), 95% CI -0.13 to 12.26; 6 studies, 454 participants). There was moderate-certainty evidence that exercise likely increases participant-reported treatment success (risk ratio (RR) 1.46, 95% CI 1.11 to 1.92; 2 studies 364 participants), and likely does not increase study withdrawals (RR 1.08, 95% CI 0.92 to 1.26; 29 studies, 2907 participants). There was low-certainty evidence that exercise may not increase adverse events (RR 2.02, 95% CI 0.62 to 6.58; 11 studies, 1684 participants). Exercise versus no treatment/usual care/limited education Compared with no treatment/usual care/limited education, low-certainty evidence indicates exercise may result in an improvement in pain immediately post-intervention (mean 13.14 points better (on a scale of 0 to 100), 95% CI 10.36 to 15.91; 56 studies, 4184 participants). Moderate-certainty evidence indicates exercise likely results in an improvement in physical function (mean 12.53 points better (on a scale of 0 to 100), 95% CI 9.74 to 15.31; 54 studies, 4352 participants) and a slight improvement in quality of life (mean 5.37 points better (on a scale of to 100), 95% CI 3.19 to 7.54; 28 studies, 2328 participants). There was low-certainty evidence that exercise may result in no difference in participant-reported treatment success (RR 1.33, 95% CI 0.71 to 2.49; 3 studies, 405 participants). There was moderate-certainty evidence that exercise likely results in no difference in study withdrawals (RR 1.03, 95% CI 0.88 to 1.20; 53 studies, 4408 participants). There was low-certainty evidence that exercise may increase adverse events (RR 3.17, 95% CI 1.17 to 8.57; 18 studies, 1557 participants). Exercise added to another co-intervention versus the co-intervention alone Moderate-certainty evidence indicates that exercise when added to a co-intervention likely results in improvements in pain immediately post-intervention compared to the co-intervention alone (mean 10.43 points better (on a scale of 0 to 100), 95% CI 8.06 to 12.79; 47 studies, 4441 participants). It also likely results in a slight improvement in physical function (mean 9.66 points better, 95% CI 7.48 to 11.97 (on a 0 to 100 scale); 44 studies, 4381 participants) and quality of life (mean 4.22 points better (on a 0 to 100 scale), 95% CI 1.36 to 7.07; 12 studies, 1660 participants) immediately post-intervention. There was moderate-certainty evidence that exercise likely increases participant-reported treatment success (RR 1.63, 95% CI 1.18 to 2.24; 6 studies, 1139 participants), slightly reduces study withdrawals (RR 0.82, 95% CI 0.70 to 0.97; 41 studies, 3502 participants), and slightly increases adverse events (RR 1.72, 95% CI 1.07 to 2.76; 19 studies, 2187 participants). Subgroup analysis and meta-regression We did not find any differences in effects between different types of exercise, and we found no relationship between changes in pain or physical function and the total number of exercise sessions prescribed or the ratio (between exercise group and comparator) of real-time consultations with a healthcare provider. Clinical significance of the findings To determine whether the results found would make a clinically meaningful difference to someone with knee OA, we compared our results to established 'minimal important difference' (MID) scores for pain (12 points on a 0 to 100 scale), physical function (13 points), and quality of life (15 points). We found that the confidence intervals of mean differences either did not reach these thresholds or included both a clinically important and clinically unimportant improvement.
AUTHORS' CONCLUSIONS: We found low- to moderate-certainty evidence that exercise probably results in an improvement in pain, physical function, and quality of life in the short-term. However, based on the thresholds for minimal important differences that we used, these benefits were of uncertain clinical importance. Participants in most trials were not blinded and were therefore aware of their treatment, and this may have contributed to reported improvements.
Overweight and obesity increase the risk of development and progression of knee osteoarthritis (OA), with higher levels of fat mass and lower levels of lean mass associated with poorer functional status. The aim was to assess changes in weight, body composition and physical function following weight loss or weight maintenance interventions in knee OA. A comprehensive search of four databases was conducted. The risk of bias was assessed using the Quality Criteria Checklist for primary research. Primary outcomes included weight, body composition and physical function; secondary outcomes were lipids, inflammatory biomarkers and muscle strength. Eleven studies were included utilizing diet and exercise (n = 4) or diet-only (n = 7) interventions, two of which were weight maintenance studies. Most studies (n = 10) reported improvements in physical function with significant weight loss, while the change in strength reported in three studies was variable. The diet and exercise studies reported an average reduction in weight of 6.7% and lean mass of 1.6 kg, with greater improvements in physical function. The diet-only studies, including weight maintenance interventions, reported greater average weight loss (7.8%) and reduction in LM (2.0 kg). Overall, better retention of lean mass and muscle strength was observed in participants with higher protein intake (≥37% of energy) and subsequently improved physical function.
BACKGROUND: Land-based exercise therapy is recommended in clinical guidelines for hip or knee osteoarthritis. Adjunctive non-pharmacological therapies are commonly used alongside exercise in hip or knee osteoarthritis management, but cumulative evidence for adjuncts to land-based exercise therapy is lacking.
OBJECTIVES: To evaluate the benefits and harms of adjunctive therapies used in addition to land-based exercise therapy compared with placebo adjunctive therapy added to land-based exercise therapy, or land-based exercise therapy only for people with hip or knee osteoarthritis.
SEARCH METHODS: We searched CENTRAL, MEDLINE, PsycINFO, EMBASE, CINAHL, Physiotherapy Evidence Database (PEDro) and clinical trials registries up to 10 June 2021.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) or quasi-RCTs of people with hip or knee osteoarthritis comparing adjunctive therapies alongside land-based exercise therapy (experimental group) versus placebo adjunctive therapies alongside land-based exercise therapy, or land-based exercise therapy (control groups). Exercise had to be identical in both groups. Major outcomes were pain, physical function, participant-reported global assessment, quality of life (QOL), radiographic joint structural changes, adverse events and withdrawals due to adverse events. We evaluated short-term (6 months), medium-term (6 to 12 months) and long-term (12 months onwards) effects.
DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility, extracted data, and assessed risk of bias and certainty of evidence for major outcomes using GRADE.
MAIN RESULTS: We included 62 trials (60 RCTs and 2 quasi-RCTs) totalling 6508 participants. One trial included people with hip osteoarthritis, one hip or knee osteoarthritis and 59 included people with knee osteoarthritis only. Thirty-six trials evaluated electrophysical agents, seven manual therapies, four acupuncture or dry needling, or taping, three psychological therapies, dietary interventions or whole body vibration, two spa or peloid therapy and one foot insoles. Twenty-one trials included a placebo adjunctive therapy. We presented the effects stratified by different adjunctive therapies along with the overall results. We judged most trials to be at risk of bias, including 55% at risk of selection bias, 74% at risk of performance bias and 79% at risk of detection bias. Adverse events were reported in eight (13%) trials. Comparing adjunctive therapies plus land-based exercise therapy against placebo therapies plus exercise up to six months (short-term), we found low-certainty evidence for reduced pain and function, which did not meet our prespecified threshold for a clinically important difference. Mean pain intensity was 5.4 in the placebo group on a 0 to 10 numerical pain rating scale (NPRS) (lower scores represent less pain), and 0.77 points lower (0.48 points better to 1.16 points better) in the adjunctive therapy and exercise therapy group; relative improvement 10% (6% to 15% better) (22 studies; 1428 participants). Mean physical function on the Western Ontario and McMaster (WOMAC) 0 to 68 physical function (lower scores represent better function) subscale was 32.5 points in the placebo group and reduced by 5.03 points (2.57 points better to 7.61 points better) in the adjunctive therapy and exercise therapy group; relative improvement 12% (6% better to 18% better) (20 studies; 1361 participants). Moderate-certainty evidence indicates that adjunctive therapies did not improve QOL (SF-36 0 to 100 scale, higher scores represent better QOL). Placebo group mean QOL was 81.8 points, and 0.75 points worse (4.80 points worse to 3.39 points better) in the placebo adjunctive therapy group; relative improvement 1% (7% worse to 5% better) (two trials; 82 participants). Low-certainty evidence (two trials; 340 participants) indicates adjunctive therapies plus exercise may not increase adverse events compared to placebo therapies plus exercise (31% versus 13%; risk ratio (RR) 2.41, 95% confidence interval (CI) 0.27 to 21.90). Participant-reported global assessment was not measured in any studies. Compared with land-based exercise therapy, low-certainty evidence indicates that adjunctive electrophysical agents alongside exercise produced short-term (0 to 6 months) pain reduction of 0.41 points (0.17 points better to 0.63 points better); mean pain in the exercise-only group was 3.8 points and 0.41 points better in the adjunctive therapy plus exercise group (0 to 10 NPRS); relative improvement 7% (3% better to 11% better) (45 studies; 3322 participants). Mean physical function (0 to 68 WOMAC subscale) was 18.2 points in the exercise group and 2.83 points better (1.62 points better to 4.04 points better) in the adjunctive therapy plus exercise group; relative improvement 9% (5% better to 13% better) (45 studies; 3323 participants). These results are not clinically important. Mean QOL in the exercise group was 56.1 points and 1.04 points worse in the adjunctive therapies plus exercise therapy group (1.04 points worse to 3.12 points better); relative improvement 2% (2% worse to 5% better) (11 studies; 1483 participants), indicating no benefit (low-certainty evidence). Moderate-certainty evidence indicates that adjunctive therapies plus exercise probably result in a slight increase in participant-reported global assessment (short-term), with success reported by 45% in the exercise therapy group and 17% more individuals receiving adjunctive therapies and exercise (RR 1.37, 95% CI 1.15 to 1.62) (5 studies; 840 participants). One study (156 participants) showed little difference in radiographic joint structural changes (0.25 mm less, 95% CI -0.32 to -0.18 mm); 12% relative improvement (6% better to 18% better). Low-certainty evidence (8 trials; 1542 participants) indicates that adjunctive therapies plus exercise may not increase adverse events compared with exercise only (8.6% versus 6.5%; RR 1.33, 95% CI 0.78 to 2.27).
AUTHORS' CONCLUSIONS: Moderate- to low-certainty evidence showed no difference in pain, physical function or QOL between adjunctive therapies and placebo adjunctive therapies, or in pain, physical function, QOL or joint structural changes, compared to exercise only. Participant-reported global assessment was not reported for placebo comparisons, but there is probably a slight clinical benefit for adjunctive therapies plus exercise compared with exercise, based on a small number of studies. This may be explained by additional constructs captured in global measures compared with specific measures. Although results indicate no increased adverse events for adjunctive therapies used with exercise, these were poorly reported. Most studies evaluated short-term effects, with limited medium- or long-term evaluation. Due to a preponderance of knee osteoarthritis trials, we urge caution in extrapolating the findings to populations with hip osteoarthritis.
BACKGROUND: Behavior change theories frameworks provide the theoretical underpinning for effective health care. The extent to which they are applied in contemporary dietetics interventions has not been explored.
OBJECTIVE: To systematically review the evidence of behavior change theory-based interventions delivered by credentialed nutrition and dietetics practitioners in primary health care settings.
METHODS: Medline, the Cumulative Index to Nursing and Allied Health Literature, PsycINFO, Embase, and Cochrane databases were searched for English language, randomized controlled trials before August 2019. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed. Eligible interventions included adults (aged ≥18 years) receiving face-to-face dietetics care underpinned by behavior change theories in primary health care settings with outcome measures targeting changes in health behaviors or health outcomes. Screening was conducted independently in duplicate and data were extracted using predefined categories. The quality of each study was assessed using the Cochrane Risk of Bias tool. The body of evidence was assessed using the Academy of Nutrition and Dietetics Evidence Analysis Manual Conclusion Grading Table.
RESULTS: Thirty articles reporting on 19 randomized controlled trials met the eligibility criteria, representing 5,172 adults. Thirteen studies (68%) showed significant improvements for the primary outcome measured. Social cognitive theory was the behavior change theory most commonly applied in interventions (n=15) with 11 finding significant intervention effects. Goal setting, problem solving, social support, and self-monitoring were the most commonly reported techniques (n=15, n=14, n=11, and n=11, respectively). Most studies had a high (n=11) or unclear (n=8) risk of bias. There was fair evidence (Grade II) supporting the use of behavior change theories to inform development of dietetics interventions.
CONCLUSIONS: Interventions delivered by credentialed nutrition and dietetics practitioners that were underpinned by behavior change theories and utilizing various behavior change techniques were found to have potential to be more effective at improving patient health outcomes than dietary interventions without theoretical underpinnings. Findings from this review should inform future primary health care research in the area of dietary behavior change. In addition, findings from this review highlight the need for stronger documentation of use of behavior change theory and techniques that map on to the theory within dietetics practice.
OBJECTIVE: To evaluate the structural effects of weight loss on hip or knee osteoarthritis (OA) and to summarize which structural joint pathologies have been examined and the evidence for the outcome measurement instruments applied.
DESIGN: Based on a pre-specified protocol (available: PROSPERO CRD42017065263), we conducted a systematic search of the bibliographic databases, Medline, Embase and Web of Science identifying longitudinal articles reporting the effects of weight loss on structural imaging outcomes in OA of the hip or knee in people who are overweight or obese.
RESULTS: From 1625 potentially eligible records, 14 articles (from 6 cohorts) were included. 2 cohorts were derived from RCTs. Evaluated pathologies were: articular cartilage (n=7), joint space width (n=3), bone marrow lesions (n=5), synovitis (n=2), effusion (n=1), meniscus (n=3), bone marrow density (n=1) and infrapatellar fat pad (IPFP; n=2). Cartilage showed conflicting results when evaluating cartilage thickness by direct thickness measurements. Compositional dGEMRIC and T2 mapping measures in early knee OA showed trends towards reduced cartilage degeneration. Joint space width on conventional radiographs showed no change. Weight loss reduced the size of the IPFP. Synovitis and effusion were not affected. Following weight loss DXA showed bone loss at the hip.
CONCLUSION: We did not find consistent evidence of the effects of weight loss on OA structural pathology in people who are overweight or obese. There is a need to achieve consensus on which structural pathologies and measurements to apply in weight loss and OA research.
OBJECTIVE: To investigate effects of long-term exercise therapy for people with knee osteoarthritis (OA) on radiographic disease severity and cartilage integrity (primary outcomes) as well as severity of bone marrow lesions (BMLs), synovitis and/or effusion (secondary outcomes).
METHODS: We sourced randomized controlled trials in people with clinical and/or radiographic OA investigating the effect of land-based exercise therapy of > 6 months on radiographic disease severity and magnetic resonance imaging outcomes of cartilage integrity (morphology or composition) as well as BML, synovitis and/or effusion severity, when compared to no exercise. Two independent reviewers extracted data and assessed risk of bias. Random-effects meta-analysis was used to pool standardised mean differences (SMD) (95% confidence intervals (CI)) or odds ratios (OR) (95% CI) and estimate heterogeneity (I2, %). Quality of the pooled body of evidence was rated implementing the GRADE approach. Studies unsuitable for meta-analysis were summarized in a best-evidence synthesis.
RESULTS: Meta-analysis showed moderate quality evidence of no treatment effect on tibiofemoral radiographic disease severity ((SMD) 95% (CI): 0.06 (-0.07, 0.20), I2 = 0%) and low-quality evidence of no effect on tibiofemoral cartilage morphology (SMD (95%): 0.06 (-0.20, 0.36), I2 = 0%). Low quality evidence revealed no treatment effect on the odds of change in synovitis ((OR) (95% CI): 0.90 (0.51,1.60), I2 = 0%) and effusion ((OR (95% CI): 0.88 (0.64, 1.20), I2 = 0%), but greater odds of tibiofemoral BMLs worsening (OR (95% CI): 1.90 (1.11, 3.26), I2 = 0%). In best-evidence synthesis, limited evidence was found for changes in patellar cartilage composition following exercise in women with mild knee OA compared to no exercise, but not for tibiofemoral cartilage.
CONCLUSION: Long-term exercise therapy did not change tibiofemoral radiographic disease severity, cartilage morphology or synovitis/effusion, but may slightly increase the likelihood for increased BML severity. Overall, meta-analysis findings were limited in directness and precision and restricted to relatively imprecise effect estimates in people who were obese on average. Limited evidence suggested some protective effects on patellar cartilage composition.
OBJECTIVES: The purposes were to (i) determine the effect of diet-only treatments and combined diet and exercise treatments on pain and physical function and (ii) explore the effect of these treatments on inflammatory biomarkers in overweight and obese adults with knee osteoarthritis.
METHODS: Five electronic databases were searched until March 2017. Randomised controlled trials investigating the effect of non-surgical non-pharmacological weight loss treatment, with or without exercise, on self-reported pain and/or physical function and/or inflammatory biomarkers were selected. Two review authors independently extracted data and assessed risk of bias for each study. Standardised mean differences (SMD) of outcomes were pooled as appropriate, using a random effects approach.
RESULTS: 2676 articles were identified, 19 met review criteria and 9 met criteria for meta-analyses. Diet-only treatments did not reduce pain (SMD -0.13; 95% confidence interval, CI: -0.37, 0.10; I2 = 49%) while a combination of diet and exercise treatments did reduce pain moderately (SMD -0.37; 95%CI: -0.69, -0.04; I2 = 54%). Physical function improved moderately with diet treatments (SMD -0.30; 95%CI: -0.52, -0.08; I2 = 47%) and combined diet and exercise treatments (SMD -0.32; 95%CI: -0.56, -0.08; I2 = 24%). Of the inflammatory markers assessed, only IL-6 reduced with diet-only treatments (SMD -0.23; 95%CI: -0.45, -0.02; I2 = 0%).
CONCLUSION: Overall, moderate pain-relief is achievable with a combination of diet and exercise, but potentially not with diet-only treatments. Findings support that either diet-only treatments or combined diet and exercise treatments moderately improve physical function. Overall, treatment effects on inflammatory biomarkers are questionable.
Worldwide prevalence of adult overweight and obesity is a growing public health issue. Adults with overweight/obesity often have chronic musculoskeletal pain. Using a mixed-methods review, we aimed to quantify the effectiveness and explore the appropriateness of weight loss interventions for this population. Electronic databases were searched for studies published between 01/01/90 and 01/07/16. The review included 14 randomized controlled trials that reported weight and pain outcomes and three qualitative studies that explored perceptions of adults with co-existing overweight/obesity and chronic musculoskeletal pain. The random-effects pooled mean weight loss was 4.9 kg (95%CI:2.9,6.8) greater for intervention vs control. The pooled mean reduction in pain was 7.3/100 units (95%CI:4.1,10.5) greater for intervention vs control. Study heterogeneity was substantial for weight loss (I2 = 95%, tau = ±3.5 kg) and pain change (I2 = 67%, tau = ±4.1%). Meta-regression slopes for the predictors of study quality, mean age and baseline mean weight on mean study weight reduction were shallow and not statistically significant (P > 0.05). The meta-regression slope between mean pain reduction and mean weight lost was shallow, and not statistically significant, -0.09 kg per unit pain score change (95%CI:-0.21,0.40, P = 0.54). Meta-synthesis of qualitative findings resulted in two synthesized findings; the importance of healthcare professionals understanding the effects of pain on ability to control weight and developing management/education programmes that address comorbidity.
Knee osteoarthritis (OA) is a major public health issue causing chronic pain, impaired physical function, and reduced quality of life. As there is no cure, self-management of symptoms via exercise is recommended by all current international clinical guidelines. This review updates one published in 2015.
OBJECTIVES:
We aimed to assess the effects of land-based exercise for people with knee osteoarthritis (OA) by comparing: 1) exercise versus attention control or placebo; 2) exercise versus no treatment, usual care, or limited education; 3) exercise added to another co-intervention versus the co-intervention alone.
SEARCH METHODS:
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and two trial registries (ClinicalTrials.gov and World Health Organisation International Clinical Trials Registry Platform), together with reference lists, from the date of the last search (1st May 2013) until 4 January 2024, unrestricted by language.
SELECTION CRITERIA:
We included randomised controlled trials (RCTs) that evaluated exercise for knee OA versus a comparator listed above. Our outcomes of interest were pain severity, physical function, quality of life, participant-reported treatment success, adverse events, and study withdrawals.
DATA COLLECTION AND ANALYSIS:
We used the standard methodological procedures expected by Cochrane for systematic reviews of interventions.
MAIN RESULTS:
We included 139 trials (12,468 participants): 30 (3065 participants) compared exercise to attention control or placebo; 60 (4834 participants) compared exercise with usual care, no intervention or limited education; and 49 (4569 participants) evaluated exercise added to another intervention (e.g. weight loss diet, physical therapy, detailed education) versus that intervention alone. Interventions varied substantially in duration, ranging from 2 to 104 weeks. Most of the trials were at unclear or high risk of bias, in particular, performance bias (94% of trials), detection bias (94%), selective reporting bias (68%), selection bias (57%), and attrition bias (48%). Exercise versus attention control/placebo Compared with attention control/placebo, low-certainty evidence indicates exercise may result in a slight improvement in pain immediately post-intervention (mean 8.70 points better (on a scale of 0 to 100), 95% confidence interval (CI) 5.70 to 11.70; 28 studies, 2873 participants). Moderate-certainty evidence indicates exercise likely results in an improvement in physical function (mean 11.27 points better (on a scale of 0 to 100), 95% CI 7.64 to 15.09; 24 studies, 2536 participants), but little to no improvement in quality of life (mean 6.06 points better (on a scale of 0 to 100), 95% CI -0.13 to 12.26; 6 studies, 454 participants). There was moderate-certainty evidence that exercise likely increases participant-reported treatment success (risk ratio (RR) 1.46, 95% CI 1.11 to 1.92; 2 studies 364 participants), and likely does not increase study withdrawals (RR 1.08, 95% CI 0.92 to 1.26; 29 studies, 2907 participants). There was low-certainty evidence that exercise may not increase adverse events (RR 2.02, 95% CI 0.62 to 6.58; 11 studies, 1684 participants). Exercise versus no treatment/usual care/limited education Compared with no treatment/usual care/limited education, low-certainty evidence indicates exercise may result in an improvement in pain immediately post-intervention (mean 13.14 points better (on a scale of 0 to 100), 95% CI 10.36 to 15.91; 56 studies, 4184 participants). Moderate-certainty evidence indicates exercise likely results in an improvement in physical function (mean 12.53 points better (on a scale of 0 to 100), 95% CI 9.74 to 15.31; 54 studies, 4352 participants) and a slight improvement in quality of life (mean 5.37 points better (on a scale of to 100), 95% CI 3.19 to 7.54; 28 studies, 2328 participants). There was low-certainty evidence that exercise may result in no difference in participant-reported treatment success (RR 1.33, 95% CI 0.71 to 2.49; 3 studies, 405 participants). There was moderate-certainty evidence that exercise likely results in no difference in study withdrawals (RR 1.03, 95% CI 0.88 to 1.20; 53 studies, 4408 participants). There was low-certainty evidence that exercise may increase adverse events (RR 3.17, 95% CI 1.17 to 8.57; 18 studies, 1557 participants). Exercise added to another co-intervention versus the co-intervention alone Moderate-certainty evidence indicates that exercise when added to a co-intervention likely results in improvements in pain immediately post-intervention compared to the co-intervention alone (mean 10.43 points better (on a scale of 0 to 100), 95% CI 8.06 to 12.79; 47 studies, 4441 participants). It also likely results in a slight improvement in physical function (mean 9.66 points better, 95% CI 7.48 to 11.97 (on a 0 to 100 scale); 44 studies, 4381 participants) and quality of life (mean 4.22 points better (on a 0 to 100 scale), 95% CI 1.36 to 7.07; 12 studies, 1660 participants) immediately post-intervention. There was moderate-certainty evidence that exercise likely increases participant-reported treatment success (RR 1.63, 95% CI 1.18 to 2.24; 6 studies, 1139 participants), slightly reduces study withdrawals (RR 0.82, 95% CI 0.70 to 0.97; 41 studies, 3502 participants), and slightly increases adverse events (RR 1.72, 95% CI 1.07 to 2.76; 19 studies, 2187 participants). Subgroup analysis and meta-regression We did not find any differences in effects between different types of exercise, and we found no relationship between changes in pain or physical function and the total number of exercise sessions prescribed or the ratio (between exercise group and comparator) of real-time consultations with a healthcare provider. Clinical significance of the findings To determine whether the results found would make a clinically meaningful difference to someone with knee OA, we compared our results to established 'minimal important difference' (MID) scores for pain (12 points on a 0 to 100 scale), physical function (13 points), and quality of life (15 points). We found that the confidence intervals of mean differences either did not reach these thresholds or included both a clinically important and clinically unimportant improvement.
AUTHORS' CONCLUSIONS:
We found low- to moderate-certainty evidence that exercise probably results in an improvement in pain, physical function, and quality of life in the short-term. However, based on the thresholds for minimal important differences that we used, these benefits were of uncertain clinical importance. Participants in most trials were not blinded and were therefore aware of their treatment, and this may have contributed to reported improvements.
