A considerable number of studies have investigated the temporal response of the peroneal muscles to sudden inversion perturbation in patients with a previous ankle sprain. The authors conducted this systematic review with meta-analysis with the purpose of synthesizing the evidence and determining if PRT impairments are present following ankle sprain. They conducted an electronic search using PubMed Central and EBSCOHost [1965-January 2013]. Articles were included if they (1) examined the PRT to sudden inversion perturbation in patients with a history of ankle sprain using a mechanical tilt platform, (2) made comparisons with a control group or contralateral limb with no history of ankle sprain, and (3) provided data for the calculation of effect sizes (ES). In addition to examining the overall effect of sustaining an ankle sprain on PRT, the effects of study design and subject characteristics on PRT were evaluated. Bias-corrected Hedge’s g ES and 95% confidence intervals (CI) were calculated to make comparisons across studies. A total of 23 studies met their inclusion parameters. The overall ES was 0.67 (95% CI=0.37, 0.95; p<0.001) indicating that a previous ankle sprain, regardless of study design or subject characteristics, resulted in moderate-to-strong PRT deficits. Further analyses determined studies with patients classified as having chronic ankle instability demonstrated large magnitude PRT deficits in between groups (ES(95% CI)=0.72(0.29, 1.14); p=0.001) and side-to-side (1.24(0.70, 1.79); p<0.001) comparisons while patients with all other ankle sprain histories demonstrated weak PRT alterations in between groups (-0.21(-1.01, 0.59); p=0.61) and side-to-side (0.21(-0.19, 0.60); p=0.31) comparisons.
The authors conclude that their meta-analyses found that individuals with a previous ankle sprain showed delayed PRT. Their further analyses determined these deficits are more evident in patients with chronic ankle instability in comparison to the contralateral uninvolved limb or a healthy control group.