Postural Control Deficits During Static Single-leg Stance in Chronic Ankle Instability: A Systematic Review and Meta-Analysis

Comparison of the effects of exergaming and balance training on dynamic postural stability during jump-landing in recreational athletes with chronic ankle instability

The primary inquiry of this study was to determine if exergaming is more effective than balance training in improving dynamic postural control during jump-landing movements among athletes with chronic ankle instability (CAI). Additionally, the study aimed to compare the effectiveness of these interventions on clinical and psychological outcomes. This study was a randomized, single-blinded, controlled trial in which participants were assigned to either an exergaming group or a balance training group. Outcome measures were assessed before, after, and one month following the intervention. Primary outcomes included the stability index (SI) and time to stabilization (TTS) in the anteroposterior (AP), mediolateral (ML), and vertical (V) directions, the dynamic postural stability index (DPSI), and the resultant vector time to stabilization (RVTTS). Secondary outcomes included performance, fear of movement, and perceived ankle instability, measured using the side-hop test, the Tampa Scale for Kinesiophobia (TSK), and the Cumberland Ankle Instability Tool (CAIT), respectively. Results indicated a significant decrease in ML SI in both groups one month after treatment compared to before and after treatment (P = 0.013 and P<0.001, respectively). Additionally, one-way ANCOVA revealed a significant difference between the groups post-treatment (F(1,31) = 6.011, P = 0.020, η2 = 0.162) and one month post-treatment (F(1,31) = 4.889, P = 0.035, η2 = 0.136), with ML SI being significantly lower in the exergaming group than the balance training group at both time points. In both group, the DPSI also decreased significantly one month post-treatment compared to before and after treatment (P = 0.040 and P = 0.018, respectively). Both groups showed improvements in performance, severity of perceived ankle instability, and fear of movement. Thus, the study concluded that both exergaming and balance training effectively improved postural control during jump-landing, with exergaming showing superior performance in the ML direction both after and one month post-treatment. In terms of clinical and psychological outcomes, both interventions were effective, with neither showing superiority over the other.

Noninstrumented Clinical Assessment of Static Postural Stability in Chronic Ankle Instability: A Systematic Review and Meta-Analysis

CONTEXT

Several clinical tests are available to assess static postural stability in individuals with chronic ankle instability (CAI); however, it is unclear which test should be used.

OBJECTIVE

To determine which noninstrumented clinical tests should be used to detect static postural stability deficits in individuals with CAI.

EVIDENCE ACQUISITION

We searched 4 databases from their inception to February 2023, and included studies comparing static postural stability in individuals with CAI and healthy controls using noninstrumented assessments. Two reviewers independently extracted study characteristics, participant information, static postural stability assessment methods, and results. We calculated the pooled standardized mean difference (SMD) and 95% confidence interval using a random effects meta-analysis and assessed the certainty of the evidence.

EVIDENCE SYNTHESIS

Fourteen cross-sectional studies (293 participants with CAI and 284 healthy controls) were included. The meta-analysis showed no significant differences between the CAI and healthy groups in the double-leg stance condition of the Balance Error Scoring System (BESS) (SMD, -0.03; low-certainty evidence). Significant group differences were found in the BESS single-leg stance (SLS) on firm and foam surfaces (SLS firm: SMD, 0.47, very low-certainty evidence; SLS foam: SMD, 0.80, very low-certainty evidence), the tandem stance (TS) on firm and foam surfaces (TS firm: SMD, 0.39, low-certainty evidence; TS foam: SMD, 0.76, low-certainty evidence), and the total BESS in the foam conditions (SMD, 1.12, very low certainty evidence). Significant differences were also found between the CAI and healthy groups in the foot-lift (SMD, 1.24; very low certainty evidence) and time-in-balance tests (SMD, -0.94; very low certainty evidence).

CONCLUSIONS

Due to the large magnitude of the differences, the SLS foam, TS foam, and the total BESS in the foam conditions, as well as the foot-lift test or time-in-balance test, may be the most appropriate to clinically identify static postural stability impairment in individuals with CAI.

Kinetic changes of gait initiation in individuals with chronic ankle instability: A systematic review

Background and Aims

Gait initiation (GI) in individuals with chronic ankle instability (CAI) has shown differences in the center of pressure (COP) and muscular measures compared to healthy controls. Some studies reported that these alterations appeared when GI was with the affected leg, while others indicated that they occurred when GI was with the non-affected leg. This systematic review aimed to understand kinetic and muscular differences between individuals with CAI, healthy controls, and the affected and non-affected legs of individuals with CAI.

Methods

PubMed, Science Direct, Web of Science, Google Scholar, and Scopus databases (1990-2023) were searched using the Population, Exposure, Comparator, and Outcome measure. The PRISMA guidelines were followed. The outcome measures were the peak and rate of COP displacement in the medial-lateral and anterior-posterior directions, and resultant plane during phases 1, 2, and 3 of COP trace during GI and the duration of each phase. The other measures included the onset time of the tibialis anterior and soleus muscle activity between individuals with CAI, healthy controls, and the affected and non-affected legs of the individuals with CAI. The studies' quality assessment was conducted based on the Strengthening the Reporting of Observational Studies in Epidemiology checklist.

Results

Five studies were included in the final evaluation. The results of included studies showed, individuals with CAI spent less time during phases 1 and 2, as well as a shorter peak of COP displacement in the lateral direction during phase 1 compared to healthy controls, regardless of whether the GI was with the affected or non-affected leg.

Conclusion

Individuals with CAI have probably adopted a strategy involving adjusting the peak of COP displacement to manage internal sway while in a single-leg stance. Overall, there was no comprehensive conclusion about differences between the two legs in individuals with CAI.

Effect of 6-week BFRT combined with IASTAM therapy on international standard dancers with chronic ankle instability

Background

In sports dance events, athletes often face the risk of ankle injury and instability, which may have a negative impact on their training and athletic performance, and even hinder their rehabilitation process and increase the likelihood of re-injury.

Objective

This study aims to observe the effects of exercise intervention (low-load ankle muscle strength training with blood flow restriction training (BFRT) equipment and balance training with blood flow restriction training equipment) combined with instrumentation therapy (Instrument-assisted soft tissue mobilization, IASTM) on ankle function, joint range of motion, and strength in sports dancers with chronic ankle instability (CAI). This study aims to provide an evidence-based approach to rehabilitation for athletes by comparing the effects of combination therapy approaches to traditional ankle strength and stability training.

Methods

Forty-two subjects with ankle instability, restriction, or discomfort were selected as observation objects and randomly divided into three groups: the combined group (n = 14, blood flow restriction training combined with IASTM), the simple blood flow restriction training group (n = 15), and the conventional ankle strength and stability training group (n = 13). The intervention lasted for 6 weeks, once a week. The three groups were assessed with the Cumberland ankle instability assessment, Foot and Ankle Ability Measure (FAAM) ankle function assessment score, and ankle range of motion measurement before intervention, after the first intervention, and after 6 weeks of intervention. The ankle strength test was compared and analyzed only before and after intervention.

Result

There was no significant difference in the participant characteristics of the three intervention groups. In terms of Cumberland Ankle Instability Tool (CAIT) scores, within-group comparisons showed that the scores after the first intervention and at the 6-week mark were significantly higher than before the intervention (P < 0.05). Between-group comparisons revealed that the combined intervention group had higher CAIT scores than the other two groups after the 6-week intervention. Regarding the FAAM functional scores, all three interventions significantly improved ankle joint function in patients with chronic ankle instability (P < 0.05), with the BFRT group showing significantly higher FAAM - Activities of Daily Living scale (FAAM-ADL) scores than the control group (P < 0.05). Both the combined and BFRT groups also had significantly higher FAAM-SPORT scores after the first intervention compared to the control (P < 0.05). In terms of ankle range of motion improvement, the combined intervention group showed a significant increase in ankle joint motion after the intervention (P < 0.05), particularly in the improvement of dorsiflexion ability (P < 0.05). As for ankle strength enhancement, all three intervention groups experienced an increase in ankle strength after the intervention (P < 0.05), with the combined intervention group showing a significant improvement in both dorsiflexion and inversion strength compared to the control group (P < 0.05).

Conclusion

BFRT combined with IASTM, isolated BFRT, and conventional ankle strength and stability training significantly improve stability, functionality, and strength in CAI patients. The combined intervention demonstrates superior efficacy in improving ankle range of motion compared to isolated BFRT and conventional approaches.

Effect of Task Constraints on Neurobiological Systems Involved in Postural Control in Individuals with and without Chronic Ankle Instability

The purpose of this study is to investigate the effect of task constraints on the neurobiological systems while maintaining postural control under various sensory feedback manipulations in individuals with and without Chronic Ankle Instability (CAI). Forty-two physically active individuals, with and without CAI, were enrolled in a case-control study conducted at a biomechanics research laboratory. All participants underwent the Sensory Organization Test (SOT), which assesses individuals' ability to integrate somatosensory, visual, and vestibular feedback to maintain postural control in double-, uninjured-, and injured-limb stances under six different conditions in which variations in the sway-referenced support surface (platform) and visual surroundings, with and without vision, are manipulated to affect somatosensory and visual feedback. Center-of-Pressure (COP) path length was computed from raw data collected during trials of each SOT condition. Sample Entropy (SampEN) values were extracted from the COP path length time series to examine neurobiological systems complexity, with lower SampEN values indicating more predictable and periodic (rigid) neurobiological systems, while higher SampEN values indicate more unpredictable and random systems. The results show that specific task constraints affect the neurobiological systems. Specifically, individuals with CAI demonstrated reduced complexity (decreased SampEN values) in the neurobiological systems during the uninjured-limb stance when all sensory feedback was intact and during both uninjured- and injured-limb stances when they were forced to rely on vestibular feedback. These results highlight the interplay between sensory feedback and task constraints in individuals with CAI and suggest potential adaptations in the neurobiological systems involved in postural control.

Patients with chronic ankle instability exhibit increased sensorimotor cortex activation and correlation with poorer lateral balance control ability during single-leg stance: a FNIRS study

Introduction

Chronic Ankle Instability (CAI) is a musculoskeletal condition that evolves from acute ankle sprains, and its underlying mechanisms have yet to reach a consensus. Mounting evidence suggests that neuroplastic changes in the brain following ankle injuries play a pivotal role in the development of CAI. Balance deficits are a significant risk factor associated with CAI, yet there is a scarcity of evidence regarding the sensorimotor cortical plasticity related to balance control in affected individuals. This study aims to evaluate the differences in cortical activity and balance abilities between patients with CAI and uninjured individuals during a single-leg stance, as well as the correlation between these factors, in order to elucidate the neurophysiological alterations in balance control among patients with CAI.

Methods

The study enrolled 24 patients with CAI and 24 uninjured participants. During single-leg stance, cortical activity was measured using a functional near-infrared spectroscopy (fNIRS) system, which included assessments of the pre-motor cortex (PMC), supplementary motor area (SMA), primary motor cortex (M1), and primary somatosensory cortex (S1). Concurrently, balance parameters were tested utilizing a three-dimensional force platform.

Results

Independent sample t-tests revealed that, compared with the uninjured individuals, the patients with CAI exhibited a significant increase in the changes of oxyhemoglobin concentration (ΔHbO) during single-leg stance within the left S1 at Channel 5 (t = 2.101, p = 0.041, Cohen's d = 0.607), left M1 at Channel 6 (t = 2.363, p = 0.022, Cohen's d = 0.682), right M1 at Channel 15 (t = 2.273, p = 0.029, Cohen's d = 0.656), and right PMC/SMA at Channel 11 (t = 2.467, p = 0.018, Cohen's d = 0.712). Additionally, the center of pressure root mean square (COP-RMS) in the mediolateral (ML) direction was significantly greater (t = 2.630, p = 0.012, Cohen's d = 0.759) in the patients with CAI. Furthermore, a moderate positive correlation was found between ML direction COP-RMS and ΔHbO2 in the M1 (r = 0.436; p = 0.033) and PMC/SMA (r = 0.488, p = 0.016), as well as between anteroposterior (AP) direction COP-RMS and ΔHbO in the M1 (r = 0.483, p = 0.017).

Conclusion

Patients with CAI demonstrate increased cortical activation in the bilateral M1, ipsilateral PMC/SMA, and contralateral S1. This suggests that patients with CAI may require additional brain resources to maintain balance during single-leg stance, representing a compensatory mechanism to uphold task performance amidst diminished lateral balance ability in the ankle joint.

Study on the effect of blood flow restriction training combined with IASTAM on ankle strength and function intervention in athletes with chronic ankle instability in sport dance events

BACKGROUND

Athletes engaged in sports dance frequently encounter the potential for ankle injuries and instability, factors that may contribute to diminished training efficacy, compromised athletic performance, prolonged recuperation, and heightened susceptibility to recurring injuries.

OBJECTIVE

The objective of this study was to investigate the impact of an exercise intervention (comprising blood flow restriction training combined with low-load ankle muscle strength training and balance training) as well as instrument-assisted soft tissue mobilization (IASTM) on the foot and ankle function, strength, and range of motion in sports dance athletes exhibiting ankle instability (CAI).

METHODS

Thirty participants exhibiting ankle instability, restriction, or discomfort were recruited and randomly assigned to two groups: the Test group (comprising blood flow restriction training combined with IASTM, n = 15) and the traditional ankle strength training group (n = 15). The intervention spanned 4 weeks, with one session per week. Assessment of the Cumberland Ankle Instability Tool (CAIT), Foot and Ankle Ability Measure (FAAM), and ankle range of motion occurred at three time points: pre-intervention, immediately following the initial intervention, and after 4 weeks of intervention. Ankle strength testing was conducted solely before and after the intervention for comparative analysis.

RESULTS

There were no significant variances in baseline characteristics between the two intervention groups. In terms of CAIT scores, both groups exhibited notably higher scores following the initial intervention and after 4 weeks of intervention compared to pre-intervention (P < 0.05). The Test group displayed higher CAIT scores than the control group, signifying a more pronounced enhancement in ankle stability among patients in the Test group. Concerning FAAM scores, both groups significantly enhanced ankle function in CAI patients (P < 0.05), with the Test group demonstrating notably higher FAAM-SPORT scores than the control group (P < 0.05), indicating superior restoration of athletic capability in the Test group. As for improvements in ankle range of motion, both groups demonstrated significant enhancements compared to pre-intervention (P < 0.05). The Test group exhibited significantly superior improvements in dorsiflexion, eversion, and inversion range of motion compared to the control group (P < 0.05), while the control group did not exhibit significant enhancements in plantarflexion and eversion range of motion (P > 0.05). Both groups displayed enhanced ankle strength in CAI patients following the intervention (P < 0.05), with the Test group manifesting notably higher dorsiflexion and inversion strength than the control group (P < 0.05).

CONCLUSION

Both blood flow restriction training combined with IASTM and traditional ankle strength and stability training have shown significant improvements in stability, function, strength, and range of motion in CAI patients. Furthermore, the Test group exhibits superior efficacy in ankle stability, daily functional movement, dorsiflexion, and eversion range of motion compared to the control group.

CLINICAL TRIAL REGISTRATION

9 February 2024, ClinicalTrials.gov, ID; NCT06251414.

Test-retest, intra- and inter-rater reliability of the reactive balance test in patients with chronic ankle instability

Introduction

The Reactive Balance Test (RBT) could be a valuable addition to research on chronic ankle instability (CAI) and clinical practice, but before it can be used in clinical practice it needs to be reliable. It has already been proven reliable in healthy recreational athletes, but not yet in patients with CAI who have shown persistent deficits in dynamic balance. The study aimed to determine the test-retest, intra-, and inter-rater reliability of the RBT in patients with CAI, and the test-retest and inter-rater reliability of the newly developed RBT score sheet.

Methods

We used a repeated-measures, single-group design to administer the RBT to CAI patients on three occasions, scored by multiple raters. We included 27 participants with CAI. The study used multiple reliability measures, including Pearson r, intra-class correlations (ICC), standard error of measurement (SEM), standard error of prediction (SEP), minimal detectable change (MDC), and Bland-Altman plots, to evaluate the reliability of the RBT's outcome measures (visuomotor response time and accuracy). It also assessed the test-retest and inter-rater reliability of the RBT score sheet using the same measures.

Results

The ICC measures for test-retest reliability were similar for accuracy (0.609) and VMRT (0.594). Intra-rater reliability had high correlations and ICCs for accuracy (r = 0.816, ICC = 0.815) and VMRT (r = 0.802, ICC = 0.800). Inter-rater reliability had a higher ICC for VMRT (0.868) than for accuracy (0.690).

Conclusion

Test-retest reliability was moderate, intra-rater reliability was good, and inter-rater reliability showed moderate reliability for accuracy and good reliability for VMRT. Additionally, the RBT shows robust SEM and mean difference measures. The score sheet method also demonstrated moderate test-retest reliability, while inter-rater reliability was good to excellent. This suggests that the RBT can be a valuable tool in assessing and monitoring balance in patients with CAI.

Insufficient recovery of proprioception in chronic ankle instability after surgical restabilization: A systematic review

Surgical repair or reconstruction of the lateral ligaments for patients with chronic ankle instability (CAI) could, logically, restore the proprioception of ankle through retensing receptors. To validate this hypothesis, seven databases were systematically searched, and thirteen studies comprising a total of 347 patients with CAI were included. Although five studies reported improved proprioceptive outcomes after surgeries, the other five studies with between-limb/group comparisons reported residual deficits at final follow-up, which does not consistently support proprioceptive recovery after existing surgical restabilization for CAI. More controlled studies are needed to provide evidence-based protocols to improve proprioceptive recovery after ankle restabilization for CAI.