The Effectiveness of Off-Loading Knee Orthoses in the Reduction of Pain in Medial Compartment Knee Osteoarthritis: A Systematic Review

Effect of using knee valgus brace on pain and activity level over different time intervals among patients with medial knee OA: systematic review

Background

The Knee valgus brace is one of the accepted conservative interventions for patients with medial compartment knee osteoarthritis to correct the knee varus and increase functional activity level. Nevertheless, comprehensive overview of the effects of using this brace on self-reported pain activity level over time is not available. Thus, this study aimed to systematically review the effect of using this brace on pain and activity levels in the last 20 years in patients with medial compartment knee osteoarthritis.

Methods

Five databases were searched to find articles from the year 2000 to the end of November 2020: Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, PubMed, Web of Science, and Scopus. Two reviewers independently evaluated the available articles for eligibility and assessed quality. The risk of bias in each study was assessed by two reviewers independently according to the Strengthening the Reporting of Observational Studies in Epidemiology tool (STROBE) for the non-randomized controlled studies and the Cochrane risk-of-bias tool for the randomized controlled studies.

Results

Seven randomized controlled studies and 17 cohort studies (in total 579 participants) were included in the systematic review. Most of these studies found using a knee valgus brace effective in reducing pain and improving activity level over different time intervals. The majority of the included studies (14 studies) evaluated the impact of the brace for a considerably short-term (less than 6 months). Thus, limited evidence is available on the long-term use of the knee valgus brace and its associated complications.

Conclusion

The knee valgus brace is an effective conservative intervention to improve the quality of life and reduce pain during daily activities for some patients. However, the long term of using this brace is still not very convenient, and the patients who benefit most from using the brace should be identified with high methodological quality studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04513-0.

Effect of knee braces and insoles on clinical outcomes of individuals with medial knee osteoarthritis: A systematic review and meta-analysis

Knee osteoarthritis is a disabling disease, causing pain and reduced function.Orthoses are used to manage this problem, including knee braces and lateral wedge insoles. However, there is still controversy on which type of intervention is more effective. This systematic review and meta-analysis aimed toevaluate the effect of knee braces and lateral wedge insoles and compare their clinical outcomes onindividuals with medial knee osteoarthritis. We conducted the search strategy based on the population, intervention, comparison, andoutcome (PICO) method. We searched with PubMed, EMBASE, Web of Science, and Scopus databases for the related studies. The articles quality assessment was done based on the modified Downs and Black checklist. Totally, we chose 32 controlled trials, including 1.849 participants, for the final evaluation. Almosttwo-thirds of the studies had a moderate quality. The overall outcome suggested that both interventionshad improved pain and function. The difference between both interventions on pain reduction was not significant (standardized mean difference = 0.12, 95% confidence interval = 0.34 to 0.1) based on meta-analysis. Both knee brace and lateral wedge insole can improve pain and function in people with knee osteoarthritis. Using either separately or both of them together are effective.

Effect of biomechanical footwear on upper and lower leg muscle activity in comparison with knee brace and normal walking

AIM

To evaluate the activity of knee stabilizing muscles while using custom-made biomechanical footwear (BF) and to compare it when walking barefoot and with a knee brace (Unloader®).

METHODS

Seventeen healthy working-aged (mean age: 29 years; standard deviation: 8 years) individuals participated. The knee brace was worn on the right knee and BF in both legs. Surface electromyography (sEMG) data was recorded bilaterally from vastus medialis (VM), semitendinosus (ST), tibialis anterior (TA) and lateral gastrocnemius (LG) muscles during walking, and repeated-measures ANOVA with a post-hoc t-test was used to determine differences between the different walking modalities (barefoot, brace and BF).

RESULTS

Averaged sEMG was significantly higher when walking with BF than barefoot or knee brace in the ST muscles, in the right LG, and left TA muscle. It was significantly lower when walking with the brace compared to barefoot in the right ST and LG muscles, and left TA muscle. Analysis of the ensemble-averaged sEMG profiles showed earlier activation of TA muscles when walking with BF compared to other walking modalities.

CONCLUSION

BF produced greater activation in evaluated lower leg muscles compared to barefoot walking. Thus BF may have an exercise effect in rehabilitation and further studies about its effectiveness are warranted.

The effect of a knee brace in dynamic motion-An instrumented gait analysis

Background

Osteoarthritis (OA) is a common problem in the older population. To reduce pain and stress in the affected knee joint compartment, a functional knee brace is often prescribed by physicians to protect it from high loads.

Objectives

An instrumented gait analysis should evaluate how the 4-point knee orthosis for varus or valgus load relief (M.4s OA) changes the kinematics of the knee, especially in the frontal plane.

Methods

17 healthy participants took part and were analyzed with an inertial sensor system (MyoMotion) giving continuous, objective information on the anatomical angles. The measurements were made both without wearing a knee brace and with the brace in different settings.

Results

The results show a significant reduction in the maximum knee abduction and raised knee adduction. The knee brace, with a strong adjustment in varus or valgus orientation, caused a shift of maximum ab-/adduction in the proposed direction in 69% and 75% of the dynamic tests, respectively. The knee motion in the frontal plane shows individual movement patterns.

Conclusion

The use of the brace leads to significant changes in the knee’s movement. Patient-specific movement patterns may explain different effects of functional knee braces on individual persons. Inertial sensors have been shown to be a low-cost, easy-to-use option for individual movement analysis and further personalized therapy.

Valgus bracing for knee osteoarthritis: a meta-analysis of randomized trials

OBJECTIVE

To evaluate the effects of valgus knee bracing on pain and function, and compliance and complications, in patients with medial knee osteoarthritis (OA).

METHODS

A meta-analysis of randomized controlled trials that compared changes in patient-reported pain and/or function in patients with medial knee OA was performed. Seven databases were searched from their inception to January 2014. Two reviewers independently determined study eligibility, rated risk of bias, and extracted data. Pooled estimates and 95% confidence intervals (95% CIs) for standardized mean differences (SMDs) for the improvement in pain (and function) were calculated. Event rates (proportions) were calculated for studies that reported complications.

RESULTS

Six studies were included in the meta-analysis. Overall, there was a statistically significant difference favoring the valgus brace group for improvement in pain (SMD 0.33 [95% CI 0.13, 0.52], P = 0.001) and function (SMD 0.22 [95% CI 0.02, 0.41], P = 0.03). When compared to a control group that did not use an orthosis, the effect size was moderate for pain (SMD 0.56 [95% CI 0.03, 1.09], P = 0.04) and function (SMD 0.48 [95% CI 0.02, 0.95], P = 0.04). When compared to a control group that used a control orthosis, only a small, statistically significant effect for pain remained (SMD 0.33 [95% CI 0.08, 0.58], P = 0.01). Instructions for brace use varied considerably and compliance ranged from 45% to 100%. Up to 25% of patients reported minor complications with brace use.

CONCLUSION

Meta-analysis of randomized trials suggests valgus bracing for medial knee OA results in small-to-moderate improvements in pain. Effect sizes vary based on study design and warrant future research.

Frontal plane corrective ability of a new unloader orthosis for medial compartment of the knee

BACKGROUND

Patients with medial compartment osteoarthritis of the knee suffer from pain and stiffness. However, current unloader braces are not being used for extended periods by knee osteoarthritis patients due to interface problems, so compliance is an issue. The aim of this study was to design a new bespoke orthosis that could be comfortable to wear while also providing the required correction to reduce medial compartment loading.

CASE DESCRIPTION AND METHODS

A new knee orthosis design was initially tested for its frontal plane correction of knee varus using a surrogate knee model. It was then assessed by a volunteer subject with grade 2 medial compartment knee osteoarthritis using a static standing radiograph.

FINDINGS AND OUTCOMES

When fitted to the surrogate knee model, the brace corrected the knee from 10° of varus to neutral alignment in the frontal plane. When worn in situ during static stance on the affected leg of the volunteer patient, it corrected the knee by 6° to a less varus position.

CONCLUSION

The orthosis provided frontal plane correction of the knee during static standing. It could therefore prove to be suitable for use by knee osteoarthritis patients.