Brain Neuroplasticity Related to Lateral Ankle Ligamentous Injuries: A Systematic Review

Proprioceptive acuity, proprioceptive weighting and balance in individuals with chronic ankle instability

BACKGROUND

Joint position sense (JPS), balance assessments, and proprioceptive weighting tests offer insights into different dimensions of proprioception to evaluate deficits associated with chronic ankle instability (CAI). However, it remains unclear whether the outcomes of one test can be extrapolated to others.

RESEARCH QUESTION

Is proprioception measured by various tests impaired, and can the result obtained in one test be extrapolated to others in CAI and control participants?

METHODS

Thirteen CAI and fifteen control participants were assessed on 1) JPS in dorsiflexion and plantarflexion by calculating absolute and constant repositioning errors. 2) Unipedal balance by measuring center of pressure (CoP) ellipse area and velocity. 3) Relative proprioceptive weighting (RPW) by measuring postural response to triceps surae and lumbar multifidus tendinous vibrations. Parameters were averaged and compared across groups using independent-sample t-tests, and correlations between parameters were analyzed using Pearson's r test.

RESULTS

No significant differences were observed between CAI and control groups for any parameter. In the CAI group only, plantarflexion absolute error was positively correlated with both CoP ellipse area (r = 0.57; P = 0.04) and anteroposterior (r = 0.57; P = 0.04) and mediolateral (r = 0.67; P = 0.01) CoP velocity. Conversely, in the control group only, plantarflexion constant error was positively correlated with RPW (r = 0.54; P = 0.04).

SIGNIFICANCE

CAI participants do not systematically exhibit proprioceptive or balance impairments. Among CAI participants only, impaired proprioceptive acuity was associated with impaired balance, and participants maintained an ankle-steered strategy even if proprioceptive signals were altered. Practitioners should assess proprioceptive acuity and balance to target potential impairments associated with CAI.

How do neuromuscular characteristics of the peroneal muscles differ in adults with and without chronic ankle instability? A systematic review with meta-analysis

BACKGROUND

Chronic ankle instability (CAI) has been associated with neuromuscular control dysfunction, particularly of the peroneal musculature.

RESEARCH QUESTION

How do neuromuscular characteristics of the peroneal muscles, including corticospinal excitability, strength, proprioception (force sense) and electromyographic measures differ in individuals with CAI compared to healthy control counterparts aged 18-45?

METHODS

A systematic review with meta-analysis was conducted by retrieving relevant articles from electronic databases including EBSCOhost (CINAHL Complete, AMED, SPORTDiscus), Ovid (MEDLINE, Embase), Web of Science, Scopus and Cochrane Library as well as Grey literature sources. The eligibility and methodological quality of the included case-control and cross-sectional studies were assessed by two reviewers. The random effects model and the standard mean difference with a 95 % confidence interval were utilised to calculate pooled estimates of the overall effect size.

RESULTS

Of the total 13,670 studies retrieved, 42 were included in the systematic review. Of these, 25 were eligible for the meta-analyses. Two of the meta-analyses, each consisting of two studies, showed less evertor force sense accuracy at 10 % (d=0.50, p = 0.03) and 20 % of maximum voluntary isometric contraction (d=1.14, p < 0.00001) in individuals with CAI than the control group. In addition, another meta-analysis of two studies showed that the CAI population had longer peroneus longus latency (d=1.69, p < 0.0001) than the control group during single-leg landing inversion perturbation test under unexpected conditions.

SIGNIFICANCE

Individuals with CAI showed specific sensorimotor impairments in evertor force sense accuracy and peroneus longus latency, which may indicate that neuromuscular dysfunction of the peroneal muscles is associated with the underlying mechanisms of the CAI pathogenesis. However, the meta-analyses are limited by the inclusion of only two studies with small sample sizes. Therefore, these findings should be cautiously interpreted, and further research is required to validate them.

Uphill Treadmill Running and Joint Mobilization Improve Dynamic Stability and Ankle Dorsiflexion Range of Motion in Young Adults With Chronic Ankle Instability: A Four-Arm Randomized Controlled Trial

OBJECTIVE

To observe the effect of uphill running and the combined effect of uphill running plus joint mobilizations on dynamic stability and ankle dorsiflexion in young adults with chronic ankle instability (CAI).

DESIGN

Four-arm randomized controlled trial.

SETTING

A college rehabilitation center.

PARTICIPANTS

Individuals with CAI (N=73).

INTERVENTIONS

Participants were randomly assigned to 4 groups: combined uphill running and joint mobilization (URJM), uphill running alone (UR), joint mobilization alone (JM), and control group. The URJM and UR groups received 20-minute running sessions, and the URJM and JM groups received ankle joint mobilizations, all 3 times a week for 4 weeks.

MAIN OUTCOME MEASURES

Cumberland Ankle Instability Tool (CAIT) and Y-balance test (YBT) in anterior, posteromedial (PM), and posterolateral (PL) directions for dynamic stability; weight-bearing lunge test and non-weight-bearing ankle dorsiflexion degree using a goniometer (NWBG) for dorsiflexion.

RESULTS

The UR group showed significant improvements in CAIT, YBT-PL, YBT-PM, and NWBG compared to the control group. The URJM group demonstrated large treatment effects in NWBG compared to both UR and JM groups. Responder analysis indicated that the UR, JM, and URJM groups had a higher likelihood of achieving clinically significant changes (exceeding minimal detectable change or minimal clinically important difference) in CAIT, YBT-PM, YBT-PL, and NWBG compared with the control group. Additionally, the combination of UR and JM was superior to either intervention alone for NWBG, with success rates 1.55 times greater than UR alone and 2.08 times greater than JM alone.

CONCLUSIONS

A 4-week UR program improves the subjective feeling of instability, dynamic postural control, and ankle dorsiflexion in young adults with CAI. Compared to UR or JM alone, their combined application can better improve the non-weight-bearing ankle dorsiflexion range of motion.

Evolving the Control-Chaos Continuum: Part 1 - Translating Knowledge to Enhance On-Pitch Rehabilitation

BACKGROUND: On-pitch rehabilitation is a crucial part of returning to sport after injury in elite soccer. The control-chaos continuum (CCC) initially offered a framework for practitioners to plan on-pitch rehabilitation, focusing on physical preparation and sport specificity. However, our experiences with the CCC, combined with recent research in injury neurophysiology, point to a need for an updated model that integrates practice design and physical-cognitive interactions. CLINICAL QUESTION: What are the insights from injury neurophysiology, soccer performance, and coaching science needed to update the CCC and improve the planning, delivery, and progression of on-pitch rehabilitation in elite soccer? KEY RESULTS: Drawing on extensive experience in elite sport, we explain how recent research on neurophysiological recovery from injury, game models, and practice design has been applied to update the CCC and evolve the existing framework. CLINICAL APPLICATION: The evolution of the CCC expands on the original model to enhance planning, delivery, and progression of on-pitch rehabilitation. The updated framework incorporates elements of visual cognition, attentional challenges, decision-making, and progressive representation of the game model to enhance sport-specific preparation for returning to sport. J Orthop Sports Phys Ther 2025;55(2):1-11. Epub 3 January 2025. doi:10.2519/jospt.2025.13158.

Knee joint pathology and efferent pathway dysfunction: Mapping muscle inhibition from motor cortex to muscle force

BACKGROUND

Dysfunction in efferent pathways after knee pathology is tied to long-term impairments in quadriceps and hamstrings muscle performance, daily function, and health-related quality of life. Understanding the underlying etiology is crucial for effective treatment and prevention of poor outcomes, such as post-traumatic osteoarthritis or joint replacement.

OBJECTIVES

To synthesize recent evidence of efferent pathway dysfunction (i.e., motor cortex, motor units) among individuals with knee pathology.

DESIGN

Commentary.

METHOD

We summarize the current literature investigating the motor cortex, corticospinal tract, and motoneuron pool in individuals with three common knee pathologies: anterior cruciate ligament (ACL) injury, anterior knee pain (AKP), and knee osteoarthritis (OA). To offer a complete perspective, we draw from studies applying a range of neuroimaging and neurophysiologic techniques.

RESULTS

Adaptations within the motor cortices, corticospinal tract, and motoneuron pool are present in those with knee pathology and underline impairments in quadriceps and hamstrings muscle function. Each pathology has evidence of altered motor system excitability and reduced volitional muscle activation and force-generating capacity, but few impairments were common across ACL injury, AKP, and OA studies. These findings underscore the central role of the motor cortex and motor unit behavior in the long-term outcomes of individuals with knee pathology.

CONCLUSIONS

Adaptations in the efferent pathways underlie persistent muscle dysfunction across three common knee pathologies. This review provides an overview of these changes and summarizes key findings from neurophysiology and neuroimaging studies, offering direction for future research and clinical application in the rehabilitation of joint injuries.

Restorative Physical Function and Patient-Reported Outcomes After Acute Lateral Ankle Sprain in High School Athletes

CONTEXT

Limited longitudinal data exist on patient-reported outcomes (PROs) after acute lateral ankle sprain (LAS). The impact of prospective hop testing on PROs at return to play (RTP) and 6 months post-RTP is unclear.

OBJECTIVE

To determine if high school athletes with an LAS who return to baseline physical function as measured by a single-leg hop for distance (SLHOP) have better PROs relative to individuals who return to symmetry.

DESIGN

Cohort study.

SETTING

Ten high schools over 2 years.

PATIENTS OR OTHER PARTICIPANTS

Two hundred six high school athletes who sustained an LAS were included. Baseline SLHOP testing was completed preinjury. Patient-reported outcomes were recorded at time of injury, RTP, and 6 months post-RTP. Participants were classified as symmetry (n = 134) or restorative (n = 72). Symmetry was defined as achieving an SLHOP performance within 10% of the uninjured limb at RTP. Restorative was defined as achieving an SLHOP performance within 10% of preinjury levels.

MAIN OUTCOME MEASURE(S)

The Foot and Ankle Ability Measure (FAAM)-Activities of Daily Living, FAAM-Sport, Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety, and PROMIS Depression were analyzed using a 2-way nonparametric analysis of variance. The interaction term of group by time was the main comparison of interest and was interpreted if significant. Post hoc multiple comparisons were performed using the Tukey-Kramer test.

RESULTS

The restorative group reported better FAAM scores at RTP and 6 months post-RTP (P < .05) relative to the symmetry group. There were no differences in PROMIS Anxiety scores at time of injury, RTP, or 6 months post-RTP between groups (P > .05). There were no differences in PROMIS Depression scores at time of injury between groups (P = .34), but the restorative group had worse PROMIS Depression scores at RTP (P = .03).

CONCLUSIONS

The restorative group reported better FAAM-ADL and FAAM-Sport scores at RTP and 6 months post-RTP relative to the symmetry group. Restoring individuals to baseline physical function rather than limb symmetry may ensure better PROs after an LAS.

Gray Matter Volumes Mediate the Relationship Between Disease Duration and Balance Control Performance in Chronic Ankle Instability

The relationship between structural changes in the cerebral gray matter and diminished balance control performance in patients with chronic ankle instability (CAI) has remained unclear. This paper aimed to assess the difference in gray matter volume (GMV) between participants with CAI and healthy controls (HC) and to characterize the role of GMV in the relationship between disease duration and balance performance in CAI. 42 participants with CAI and 33 HC completed the structural brain MRI scans, one-legged standing test, and Y-balance test. Regional GMV was measured by applying voxel-based morphometry methods. The result showed that, compared with HC, participants with CAI exhibited lower GMV in multiple brain regions (familywise error [FWE] corrected p < 0.021). Within CAI only, but not in HC, lower GMV in the thalamus (β = -0.53, p = 0.003) and hippocampus (β = -0.57, p = 0.001) was associated with faster sway velocity of the center of pressure (CoP) in eyes closed condition (i.e., worse balance control performance). The GMV in the thalamus (percentage mediated [PM] = 32.02%; indirect effect β = 0.119, 95% CI = 0.003 to 0.282) and hippocampus (PM = 33.71%; indirect effect β = 0.122, 95% CI = 0.005 to 0.278) significantly mediated the association between the disease duration and balance performance. These findings suggest that the structural characteristics of the supraspinal elements is critical to the maintenance of balance control performance in individuals suffering from CAI, which deserve careful consideration in the management and rehabilitation programs in this population.

Reduction in preparatory brain activity preceding gait initiation in individuals with chronic ankle instability: A movement-related cortical potential study

Evidence suggests that chronic ankle instability (CAI) is not merely a peripheral musculoskeletal injury but should be recognized as a neurophysiological dysfunction. This reflects a paradigm shift from focusing on peripheral structural changes to emphasizing the central nervous system. However, changes in cortical activity during functional activities remain poorly understood. Thus, this study aimed to compare preparatory brain activity during gait initiation (GI) through movement-related cortical potentials (MRCPs) in individuals with CAI and healthy subjects. The proactive components of MRCPs, including contingent negative variation (CNV) and event-related desynchronization (ERD), were measured using electroencephalography. The primary outcomes were late CNV amplitude, CNV peak amplitude, CNV peak time, and alpha/beta ERD. The results indicated that the late CNV amplitude was significantly lower in the CAI group compared to the healthy group at the Fz and Cz electrodes (P < 0.001). The CAI group also demonstrated lower CNV peak amplitude at the Fz, Cz, and Pz electrodes (P < 0.0025). Additionally, in the CAI group, signals peaked earlier at the Cz electrode (P = 0.002). Furthermore, alpha ERD at Pz was significantly lower in the CAI group than in the healthy group (P = 0.003), suggesting diminished preparatory brain activity during GI in CAI subjects. Recognizing CAI as a condition involving both peripheral and central dysfunctions highlights the importance of a multidisciplinary approach in treatment and rehabilitation. This approach should target brain activity in addition to peripheral structures, potentially leading to improved long-term outcomes for patients.

Effects of transcranial direct current stimulation combined with Bosu ball training on the injury potential during drop landing in people with chronic ankle instability

Purpose

To investigate the effects of transcranial direct current stimulation (tDCS) combined with Bosu ball training on the injury potential during drop landing in people with chronic ankle instability (CAI).

Methods

A total of 40 participants with CAI were recruited and randomly divided into the tDCS + Bosu and Bosu groups. The people in the tDCS + Bosu group received intervention of tDCS combined with Bosu ball training, and those in the Bosu group received intervention of sham tDCS and Bosu ball training, for 6 weeks with three 20-min sessions per week. Before (week0) and after (week7) the intervention, all participants drop-landed on a trap-door device, with their affected limbs on a moveable platform, which could be flipped 24° inward and 15° forward to mimic an ankle inversion condition. The kinematic data were captured using a twelve-camera motion capture system. Two-way ANOVA with repeated measures was used to analyze data.

Results

Significant group-by-intervention interactions were detected in the peak ankle inversion angular velocity (p = 0.047, η2 p = 0.118), the time to peak ankle inversion (p = 0.030, η2 p = 0.139), and the plantarflexion angle at the moment of peak ankle inversion (p = 0.014, η2 p = 0.173). Post hoc comparisons showed that compared with week0, the peak ankle inversion angular velocity and the plantarflexion angle at the moment of peak ankle inversion were reduced, the time to peak ankle inversion was advanced in both groups at week7, and the changes were greater in the tDCS + Bosu group compared to the Bosu group. And, a significant intervention main effect was detected in the peak ankle inversion angle in the two groups (p < 0.001, η2 p = 0.337).

Conclusion

Compared with the Bosu ball training, the tDCS combined with Bosu ball training was more effective in reducing the injury potential during drop landing in people with CAI.

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.

Individuals With Chronic Ankle Instability Show Abnormalities in Maximal and Submaximal Isometric Strength of the Knee Extensor and Flexor Muscles

BACKGROUND

It has been shown that chronic ankle instability (CAI) leads to abnormalities in neuromuscular control of more proximal joints than the ankle. Although strength of the hip and the ankle muscles has been largely investigated providing concordant results, limited evidence with contrasting results has been reported regarding knee extensor and flexor muscles.

PURPOSE

To investigate maximal and submaximal isometric muscle strength in individuals with CAI.

STUDY DESIGN

Controlled laboratory study.

METHODS

Fifteen participants with unilateral CAI and 15 healthy matched controls were recruited. To quantify maximal strength, peak forces were recorded during a maximal isometric voluntary contraction of knee extensor and flexor muscles at 30° and 90° of knee flexion and normalized by the body weight of each participant. At both angles, submaximal isometric contractions at 20%, 50%, and 80% of the maximal voluntary isometric contraction were performed to analyze strength steadiness, in terms of coefficient of variation, and strength accuracy, in terms of absolute error. During all the assessments, knee extensor and flexor muscle activation was recorded by means of surface electromyography.

RESULTS

Knee flexor maximal isometric strength was significantly lower in the injured limb of individuals with CAI in comparison with healthy controls at both 30° (0.15 ± 0.05 vs 0.20 ± 0.05; P < .05) and 90° (0.14 ± 0.04 vs 0.18 ± 0.05; P < .05). Knee extensor and flexor steadiness was significantly lower (higher coefficient of variation) in both the injured and the noninjured limbs of individuals with CAI in comparison with healthy individuals at 90° and at 30° for knee flexor steadiness of the injured limb. Knee extensor and flexor accuracy was lower (higher absolute error) in both the injured and noninjured limbs of individuals with CAI in comparison with healthy individuals, mainly at 30°, while at 90° it was lower only in the injured limb. No differences between the 2 groups were found for maximal isometric strength of knee extensor muscles, as well as for muscle activations.

CONCLUSION

Individuals with CAI show abnormalities in maximal and submaximal isometric strength of knee flexor muscles, and submaximal strength of the knee extensor muscles. Further studies should deeply investigate mechanisms leading to these abnormalities.

CLINICAL RELEVANCE

Rehabilitation interventions should consider abnormalities of neuromuscular control affecting joints more proximal than the ankle in individuals with CAI.

REGISTRATION

NCT05273177 (ClinicalTrials.gov identifier).

Deficits in neurocognitive performance in patients with chronic ankle instability during a neurocognitive balance task - A retrospective case-control study

OBJECTIVES

To assess the neurocognitive performance while maintaining balance of patients experiencing CAI compared to healthy controls. In patients with CAI, the affected limb was also compared to the contralateral limb.

DESIGN

A retrospective case-control study.

SETTING

Laboratory study.

PARTICIPANTS

We included 27 patients with CAI and 21 healthy controls.

METHODS

The study consisted of two sessions, namely familiarisation and experimentation, which were scheduled with a gap of at least one week between them. During the experimental trial, both groups performed the Y-Balance Test and Reactive Balance Test once on each limb.

MAIN OUTCOME MEASURES

The main outcome measures are accuracy and visuomotor response time (VMRT) calculated via video-analysis and with the Fitlight™-hardware and software respectively during the Reactive Balance Test (RBT).

RESULTS

No data was excluded from the final analysis. Patients with CAI exhibited significantly lower accuracy than healthy controls, with a mean difference of 8.7% (±3.0)%. There were no differences for VMRT between groups. Additionally, no significant differences were observed between the affected and contralateral limb of the patient group for both accuracy and VMRT.

CONCLUSIONS

Patients with CAI showed lower accuracy, but similar VMRT compared to healthy controls during a neurocognitive balance task, indicating impaired neurocognitive function. Patients exhibit comparable speed to healthy individuals when completing neurocognitive balance tasks, yet they display a higher frequency of accuracy errors in accurately perceiving their environment and making decisions under time constraints. Future research should gain more insights in which other cognitive domains are affected in patients with CAI for a better grasp of this condition's underlying mechanism.

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.

The effects of kinesiophobia on postural control with chronic ankle instability

BACKGROUND

Patients with chronic ankle instability (CAI) often experience injury-related fear following ankle injuries, a condition known as kinesiophobia. Little research has investigated the impact of kinesiophobia in patients with CAI.

RESEARCH QUESTION

How does kinesiophobia impact the static and dynamic balance of individuals with CAI?

METHODS

Fifty patients with CAI were divided into 2 subgroups based on their responses to the Tampa Scale of Kinesiophobia: 25 with kinesiophobia (CAI-K) and 25 without kinesiophobia (CAI-N). These groups were compared to 20 control participants. All participants performed a single-leg balance test with eyes open (EO) and eyes closed (EC). They also performed the Y-balance test (YBT) with EO. Romberg ratios were calculated as EC/EO and used for statistical analysis.

RESULTS

No differences in static balance with EO and EC were found among three groups. However, the CAI-K group displayed a higher Romberg ratio in the mediolateral direction during static balance than both CAI-N and control groups. Additionally, both CAI-K and CAI-N groups displayed higher Romberg ratio in the anterior-posterior than controls. During YBT, the CAI-K group showed reduced reach distance in the anterior direction than CAI-N and control groups.

SIGNIFICANCE

The CAI-K group relies more on visual feedback during static balance in the mediolateral direction than CAI-N and control groups. Furthermore, the CAI-K group displayed less anterior reach distance during YBT compared to the CAI-N and control groups. Clinicians should consider both psychological and physical factors when designing rehabilitation programs.