The Effects of Balance Training on Balance Performance and Functional Outcome Measures Following Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BackgroundSeveral studies have examined the effects of balance training in elderly individuals following total knee arthroplasty (TKA), although findings appear to be equivocal.ObjectivesThis systematic review and meta-analysis examined the effects of balance training on walking capacity, balance-specific performance and other functional outcome measures in elderly individuals following TKA.MethodsData sources: Pubmed, PEDro, Cinahl, SportDiscus, Scopus. Eligibility criteria: Data were aggregated following the population-intervention-comparison-outcome (PICO) principles. Eligibility criteria included: (1) randomised controlled trials; (2) studies with comparative groups; (3) training interventions were incorporated post-TKA; and (4) outcome measures included walking capacity, balance-specific performance measures, subjective measures of physical function and pain and knee range-of-motion. Participants: Elderly individuals (65+years) who underwent total knee arthroplasty. Interventions: Balance interventions that consisted of balance exercises, which were compared to control interventions that did not involve balance exercises, or to a lesser extent. Participants also undertook usual physiotherapy care in conjunction with either the balance and/or control intervention. The intervention duration ranged from 4 to 32weeks with outcome measures reported immediately following the intervention. Of these, four studies also reported follow-up measures ranging from 6 to 12months post-interventions. Study appraisal: PEDro scale.Synthesis methodsQuantitative analysis was conducted by generating forest plots to report on standardised mean differences (SMD; i.e. effect size), test statistics for statistical significance (i.e. Z values) and inter-trial heterogeneity by inspecting I-2. A meta-regression was also conducted to determine whether training duration predicted the magnitude of SMD.ResultsBalance training exhibited significantly greater improvement in walking capacity (SMD=0.57; Z=6.30; P<0.001; I-2=35%), balance-specific performance measures (SMD=1.19; Z=7.33; P<0.001; I-2=0%) and subjective measures of physical function (SMD=0.46; Z=4.19; P<0.001; I-2=0%) compared to conventional training immediately post-intervention. However, there were no differences in subjective measures of pain (SMD=0.77; Z=1.63; P>0.05; I-2=95%) and knee range-of-motion (SMD=0.05; Z=0.39; P>0.05; I-2=1%) between interventions. At the 6- to 12-month follow-up period, improvement in combined measures of walking capacity and balance performance (SMD=041; Z=3.55; P<0.001; I-2=0%) were significantly greater for balance training compared to conventional training, although no differences were observed for subjective measures of physical function and pain (SMD=0.26; Z=2.09; P>0.05; I-2=0%). Finally, the training duration significantly predicted subjective measures of pain and physical function (r(2)=0.85; standardised =0.92; P<0.001), although this was not observed for walking capacity and balance-specific performance measures (r(2)=0.02; standardised =0.13; P=0.48).LimitationsA number of outcome measures indicated high inter-trial heterogeneity and only articles published in English were included.ConclusionBalance training improved walking capacity, balance-specific performance and functional outcome measures for elderly individuals following TKA. These findings may improve clinical decision-making for appropriate post-TKA exercise prescription to minimise falls risks and optimise physical function.