Biomechanical effects of valgus knee bracing: a systematic review and meta-analysis

Abstract

To review and synthesize the biomechanical effects of valgus knee bracing for patients with medial knee osteoarthritis (OA). Electronic databases were searched from their inception to May 2014. Two reviewers independently determined study eligibility, rated study quality and extracted data. Where possible, data were combined into meta-analyses and pooled estimates with 95% confidence intervals (CI) for standardized mean differences (SMD) were calculated. Thirty studies were included with 478 subjects tested while using a valgus knee brace. Various biomechanical methods suggested valgus braces can decrease direct measures of medial knee compressive force, indirect measures representing the mediolateral distribution of load across the knee, quadriceps/hamstring and quadriceps/gastrocnemius co-contraction ratios, and increase medial joint space during gait. Meta-analysis from 17 studies suggested a statistically significant decrease in the external knee adduction moment (KAM) during walking, with a moderate-to-high effect size (SMD = 0.61; 95% CI: 0.39, 0.83; P < 0.001). Meta-regression identified a near-significant association for the KAM effect size and duration of brace use only (β, -0.01; 95% CI: -0.03, 0.0001; P = 0.06); with longer durations of brace use associated with smaller treatment effects. Minor complications were commonly reported during brace use and included slipping, discomfort and poor fit, blisters and skin irritation. Systematic review and meta-analysis suggests valgus knee braces can alter knee joint loads through a combination of mechanisms, with moderate-to-high effect sizes in biomechanical outcomes.

Strategies for the prevention of knee osteoarthritis

“…This combination, or the brace alone, decreases pain and somewhat shifts the load in the knee from the medial to the lateral side. [83][84][85][86][87][88][89] This change in load or contact stress might delay or prevent the onset of OA. In a randomized study in patients with patellofemoral OA, bracing was associated with pain relief and a decreased volume of bone marrow lesions in the affected compartment.…”

“…In a randomized study in patients with patellofemoral OA, bracing was associated with pain relief and a decreased volume of bone marrow lesions in the affected compartment. 90 These strategies could be used to prevent future OA, but poor compliance is currently a problem, 88,89 and further development of devices and clinical studies are needed.…”

Longitudinal Changes in the Total Knee Joint Moment After Anterior Cruciate Ligament Reconstruction Correlate With Cartilage Thickness Changes

“…The associations between changes in KFM and KAM contributions to the TJM and cartilage thickness ratio changes in the ACLR limb provide support for load modifying interventions to alter gait mechanics following ACLR. For example, gait retraining, bracing, lateral wedging, and specialized footwear can reduce the KAM and could be explored in the ACLR population. Furthermore, extended rehabilitation or interventions aiming to improve quadriceps function/KFM after ACLR could be investigated in future work.…”

Comparison between in vitro and in vivo cartilage overloading studies based on a systematic literature review

“…However, it is complicated to determine the isolated effect of loading since it is impossible to measure in vivo loads. For bracing, it has been shown that improvement in pain is small‐to‐moderate while improvement in gait mechanics was moderate‐to‐high . It has also been demonstrated that the placebo effect can play a role in patient experience .…”