Sensorimotor deficits with ankle sprains and chronic ankle instability. Clin Sports Med. 2008;27:353-370, vii. [PMID: 18503872 DOI: 10.1016/j.csm.2008.03.006]

Optical flow balance perturbations alter gait kinematics and variability in chronic ankle instability patients

BACKGROUND

Individuals with chronic ankle instability (CAI) have known balance impairments thought to be the result of an inability to reweight sensory information. CAI patients place greater emphasis on visual information during single-limb stance than healthy controls but this evidence is based on removing visual information during static conditions.

RESEARCH QUESTION

Does perturbed optical flow effect step kinematics and variability in those with CAI differently than healthy controls? What is the relationship among ankle laxity, plantar cutaneous sensation, and susceptibility to perturbed optical flow in those with CAI?

METHODS

17 CAI patients and 17 healthy individuals participated in a crossover experimental study. Participants walked on a treadmill at 1.25 m/s while watching a speed-matched virtual hallway with and without continuous mediolateral (ML) optical flow perturbations. Three-dimensional pelvic and foot kinematics were recorded at 100 Hz for at least 300 consecutive steps in each condition. Step width (SW) and step length (SL) values were calculated from consecutive heel positions. Gait variability was characterized as the standard deviation of step width (SWV), step length (SLV), and ML sacrum motion (SMV) across all steps performed in each condition.

RESULTS

The CAI group exhibited a greater change in SWV (p = 0.037), SLV (p = 0.040), and ML SMV (p = 0.047) from the perturbed to unperturbed conditions relative to the healthy controls. A condition main effect was also noted for SW (p < 0.001) and SL (p < 0.001) as ML optical flow perturbations resulted in significant changes in SW and SL relative to the normal walking condition.

SIGNIFICANCE

Walking with ML optical flow perturbations induced greater variability changes in those with CAI relative to controls. When combined with the existing literature, this finding suggests that CAI individuals have a greater reliance on visual information in both static and dynamic (i.e. walking gait) conditions relative to healthy individuals.

Effect of Combined Balance Exercises and Kinesio Taping on Balance, Postural Stability, and Severity of Ankle Instability in Female Athletes with Functional Ankle Instability

Ankle sprain is a common musculoskeletal injury, and recurrent ankle sprains often lead to ankle instability. This study aimed to examine whether a 6-week balance training on a wobble board (WB) combined with kinesio taping (KT) is effective in improving balance, postural stability, and ankle stability among female athletes with functional ankle instability (FAI). Twenty-four female athletes with FAI were randomly assigned to study (SG) or control groups (CG). SG attended a 6-week training protocol of combined balance training on the wobble board with KT applied to ankles during exercise. CG only went through a 6-week balance training procedure that was the same as the SG. Before and after the training program, balance and postural stability and the severity of ankle instability were assessed by single-leg Biodex Balance system and Cumberland Ankle Instability Tool (CAIT), respectively. The analysis revealed that the scores of balance and postural stability decreased after the 6-week training for CG (p = 0.002) and SG (p = 0.001), which indicates an improvement for these variables, and the score of CAIT increased, which means the severity of instability reduced (p = 0.001 for both groups). Significant between-group differences were found for balance and postural stability (t = 2.79, p = 0.011, g = −1.99) and the severity of instability (t = 2.082, p = 0.049, g = 1.36), favoring SG compared with CG. This study showed that the addition of KT to balance training is more effective than balance training alone in improving balance, postural stability, and severity of ankle instability in female athletes with FAI. Our findings could provide a preliminary reference for designing combined balance and KT programs for delivering health benefits to females with FAI.

Effects of Stroboscopic Vision on Postural Control in Individuals With and Without Chronic Ankle Instability

Objectives: Patients with chronic ankle instability (CAI) tend to increase their reliance on visual information, perhaps to compensate for proprioceptive deficits which appear after lateral ankle sprains. However, little is known about how limited visual feedback would alter static postural control in patients with CAI compared with copers and controls. The purpose of this study was to identify the effects of reduced visual feedback via stroboscopic glasses on static balance among CAI, coper, and uninjured control participants. Design: Controlled trial in a laboratory setting. Methods: Nineteen patients with CAI, 19 copers, and 19 controls participated in this study. Each participant performed a single-leg balance test with eyes open, stroboscopic vision, and eyes closed. Two-way analysis of variance (group × condition) was used to examine the differences between condition (eyes open, stroboscopic vision, and eyes closed) and group (CAI, coper, and control). Results: There were no significant interactions for static balance. Although there were no group effects among 3 groups for all static postural control measures, visual condition main effects were present (P < .01) for each dependent variable. Across all groups, anterior–posterior and mediolateral center of pressure path length and center of pressure velocity with stroboscopic vision were greater than the condition with eyes open (P < .01) and less than with eyes closed (P < .01). Conclusions: Stroboscopic glasses could be cost effective visual disruption equipment during static postural control regardless of ankle injury history. However, incorporating static balance with limited visual information via stroboscopic glasses could not display the differences in visual reliance in individuals with and without CAI.

Hip strength, quadriceps strength and dynamic balance are lower in people with unilateral knee osteoarthritis compared to their non-affected limb and asymptomatic controls

BACKGROUND

There is insufficient literature on multi-directional hip strength differences and dynamic balance between people with knee osteoarthritis (KOA) and healthy controls.

OBJECTIVE

In people with unilateral KOA, determine if hip/knee strength and dynamic balance differs (i) between sides, and (ii) compared to controls.

METHODS

Thirty-six participants (17 women; 65.5 ± 8.9 years) with unilateral KOA and 36 age- and sex-matched controls were included in a cross-sectional study. Outcomes included hip strength, quadriceps strength, and dynamic balance (three directions) during the Star Excursion Balance Test. Mixed ANOVA analysis was completed to investigate differences between Limbs and Groups. Mean differences (MD) and 95% confidence intervals (CI) were calculated.

RESULTS

Quadriceps and hip adduction strength were 16% (95%CI:10, 22) and 9% [95%CI: 3, 16) lower on the affected compared to non-affected side. Quadriceps and hip abduction, adduction, flexion, and extension strength (MD varying from 16%, 95%CI: 8, 25; to 34%, 95%CI: 17, 50) were weaker bilaterally in individuals with KOA compared to control. Posteromedial balance was 4% (95%CI: 2, 6) lower for affected compared to non-affected limbs in those with KOA and 13% (95%CI: 6, 21) lower in the affected limb compared to controls. Individuals with KOA had lower balance bilaterally in the anterior 11% (95%CI: 7, 15) and posterolateral 21% (95%CI: 13, 30) directions.

CONCLUSION

Hip/knee strength (especially in the sagittal and frontal planes) and dynamic balance are lower bilaterally in people with KOA compared to controls. Hip adduction strength is lower on the affected than non-affected limbs of people with KOA. Clinicians should consider that knee extension strength, hip strength, and dynamic balance are lower bilaterally in people with unilateral KOA.

Corticospinal activity during a single-leg stance in people with chronic ankle instability

PURPOSE

The aim of the study was to determine whether corticospinal excitability and inhibition of the tibialis anterior during single-leg standing differs among individuals with chronic ankle instability (CAI), lateral ankle sprain copers, and healthy controls.

METHODS

Twenty-three participants with CAI, 23 lateral ankle sprain copers, and 24 healthy control participants volunteered. Active motor threshold (AMT), normalized motor-evoked potential (MEP), and cortical silent period (CSP) were evaluated by transcranial magnetic stimulation while participants performed a single-leg standing task.

RESULTS

Participants with CAI had significantly longer CSP at 100% of AMT and lower normalized MEP at 120% of AMT compared to lateral ankle sprain copers (CSP_100%: p = 0.003; MEP_120%: p = 0.044) and controls (CSP_100%: p = 0.041; MEP_120%: p = 0.006).

CONCLUSION

This investigation demonstrate altered corticospinal excitability and inhibition of the tibialis anterior during single-leg standing in participants with CAI. Further research is needed to examine the effects of corticospinal maladaptations to motor control of the tibial anterior on postural control performance in those with CAI.

Dynamic reach deficits in those with chronic ankle instability: A systematic review and meta-analysis

OBJECTIVE

The purpose of this review with meta-analyses was to determine the dynamic reach differences 1) between chronic ankle instability (CAI) and uninjured individuals, 2) between the limbs of an individual with CAI, and 3) between the uninvolved CAI limb and the healthy control limb across all possible reach directions of the Star Excursion Balance Test (SEBT).

METHODS

PubMed, CINAHL, SPORTDiscus, and Scopus databases were searched up to October 2021. Data were extracted from the retained studies and underwent methodological quality assessment and meta-analysis using random-effect models.

RESULTS

After screening, 33 articles were included for the analyses. In all possible SEBT reach directions, the CAI group demonstrated significantly decreased normalized dynamic reach distances relative to the uninjured control group (SMDs: -0.66 to -0.48, p ≤ 0.05). Similarly, the involved CAI limb demonstrated significantly decreased normalized dynamic reach distances relative to the uninvolved CAI limb (SMDs: -0.61 to -0.33, p ≤ 0.05). However, no differences were noted between the uninvolved CAI limb and the healthy control limb (SMDs: -0.22 to 0.09, p ≥ 0.13).

CONCLUSIONS

Our findings were that the involved limb of those with CAI has dynamic postural deficits relative to (i) an uninjured control group and (ii) relative to their uninvolved limb. However, the uninvolved limb of the CAI group does not differ from an uninjured control group in any reach direction.

The Star Excursion Balance Test: An Update Review and Practical Guidelines

The Star Excursion Balance Test (SEBT) is a reliable, responsive, and clinically relevant functional assessment of lower limbs’ dynamic postural control. However, great disparity exists regarding its methodology and the reported outcomes. Large and specific databases from various population (sport, age, and gender) are needed to help clinicians when interpreting SEBT performances in daily practice. Several contributors to SEBT performances in each direction were recently highlighted. The purpose of this clinical commentary is to (a) provide an updated review of the design, implementation, and interpretation of the SEBT and (b) propose guidelines to standardize SEBT procedures for better comparisons across studies.

Reliability and usefulness of the single leg heel raise balance test in patients with chronic ankle instability

We aimed to analyze the differences in static (including conventional and modified [single-leg heel-raise balance]) and dynamic postural stability and muscle endurance between patients with chronic ankle instability (CAI) and healthy controls, and to determine the reliability and usefulness of the single-leg heel-raise balance test in patients with CAI. In total, 26 patients with CAI and 26 healthy controls were enrolled. Postural stability was assessed using a postural stabilometry system. Muscle endurance was measured in dorsiflexion and plantarflexion using an isokinetic device. Modified static postural stability (P < 0.001) and dynamic postural stability (P < 0.001) were significantly poorer in the affected ankles of patients with CAI than in the controls. Plantarflexion endurance was significantly lower in the affected ankles of the patients with CAI than in the controls (P = 0.023). Modified static postural stability significantly correlated with plantarflexion endurance in both groups (CAI group: r = - 0.470, P = 0.015; healthy controls group: r = - 0.413, P = 0.036). Plantarflexion endurance was a significant risk factor for modified static postural stability in both the CAI group (R² = 0.221, P = 0.015) and healthy controls (R² = 0.170, P = 0.036). Given the reliability of the modified static postural stability test, clinicians and therapists should consider using it to assess improvements in postural stability and muscle endurance in patients with CAI before and after rehabilitation.

Muscle activations during functional tasks in individuals with chronic ankle instability: a systematic review of electromyographical studies

BACKGROUND

It has been reported that individuals with chronic ankle instability (CAI) show motor control abnormalities. The study of muscle activations by means of surface electromyography (sEMG) plays a key role in understanding some of the features of movement abnormalities.

RESEARCH QUESTION

Do common sEMG activation abnormalities and strategies exists across different functional movements?

METHODS

Literature review was conducted on PubMed, Web-of-Science and Cochrane databases. Studies published between 2000 and 2020 that assessed muscle activations by means of sEMG during any type of functional task in individuals with CAI, and used healthy individuals as controls, were included. Methodological quality was assessed using the modified Downs&Black checklist. Since the methodologies of different studies were heterogeneous, no meta-analysis was conducted.

RESULTS

A total of 63 articles investigating muscle activations during gait, running, responses to perturbations, landing and hopping, cutting and turning; single-limb stance, star excursion balance task, forward lunges, ball-kicking, y-balance test and single-limb squatting were considered. Individuals with CAI showed a delayed activation of the peroneus longus in response to sudden inversion perturbations, in transitions between double- and single-limb stance, and in landing on unstable surfaces. Apparently, while walking on ground there are no differences between CAI and controls, walking on a treadmill increases the variability of muscles activations, probably as a "safety strategy" to avoid ankle inversion. An abnormal activation of the tibialis anterior was observed during a number of tasks. Finally, hip/spine muscles were activated before ankle muscles in CAI compared to controls.

CONCLUSION

Though the methodology of the studies herein considered is heterogeneous, this review shows that the peroneal and tibialis anterior muscles have an abnormal activation in CAI individuals. These individuals also show a proximal muscle activation strategy during the performance of balance challenging tasks. Future studies should investigate whole-body muscle activation abnormalities in CAI individuals.

Effectiveness of balance training in patients with chronic ankle instability: protocol for a systematic review and meta-analysis

INTRODUCTION

Lateral ankle sprains are one of the most common musculoskeletal injuries. Up to 70% of individuals who sustain lateral ankle sprains develop chronic ankle instability (CAI). Balance training has been used in patients with CAI, but the evidence for its efficacy is inconsistent. This systematic review and meta-analysis aims to determine the short-term (end of the treatment period) and long-term (6 months after treatment) effectiveness of balance training for patients with CAI.

METHODS AND ANALYSIS

We will search PubMed, EMBASE, the Cochrane Library, Ovid, EBSCO-host, Pedro, ClinicalKey, ScienceDirect, Springer, China National Knowledge Infrastructure, Technology Periodical Database (VIP), WanFang Data and China Biology Medicine for reports of randomised trials of balance training in patients with CAI, from inception to 1 October 2021. The language will be restricted to English and Chinese, and articles will be screened and collected by two reviewers independently. Dynamic balance and functional ankle instability are the primary outcomes of this study. Secondary outcomes include pain, ankle range of motion, ankle strength and health-related quality of life. Review Manager V.5.3 software will be used for meta-analysis, and stratification analysis will be conducted for study quality according to the Jadad score. Subgroup and sensitivity analyses will be conducted. Grading of Recommendations, Assessment, Development and Evaluation will be used to assess confidence in the cumulative evidence. The protocol follows the Cochrane Handbook for Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols guidelines.

ETHICS AND DISSEMINATION

Ethical approval is not required for literature-based studies. The results will be disseminated through peer-reviewed publications.

Effects of posture and lower limb muscle strength on the results of the Star Excursion Balance Test

[Purpose] This study aimed to clarify the relationship between the distance measurements in the Star Excursion Balance Test and participants’ posture and lower limb muscle strength. [Participants and Methods] Nine healthy male college students participated in this study. Star Excursion Balance Test distance was measured in both lower limbs by performing anterior, posterolateral, and posteromedial trials; measuring the maximum reach; and performing three-dimensional motion analysis to determine the posture at maximum reach. Isokinetic muscle strength for knee flexion/extension, hip flexion/extension, and hip adduction/abduction were measured using an isokinetic machine. [Results] The hip extension strength, reach side ankle dorsiflexion angles, stance side knee flexion, reach side knee flexion, and knee flexion strength were selected as significant explanatory variables in the anterior direction. For the posteromedial direction, hip adduction and hip extension strength, reach side hip flexion angle, and stance side hip flexion angle were selected. For the posterolateral direction, reach side knee flexion angle and stance side ankle dorsiflexion, knee flexion strength and reach side hip flexion angle were selected. [Conclusion] The related factors differed between the dominant and non-dominant legs even in the same reach direction.

Correlations of Single-Leg Performance Tests to Patient-Reported Outcomes After Primary Anterior Cruciate Ligament Reconstruction

OBJECTIVE

To determine the relationship between patient-reported outcomes (PROs) to the single-leg step-down test (SLSD) and the Y-balance anterior reach (YB-A) 6 months after primary anterior cruciate ligament reconstruction (ACLR).

DESIGN

Cross-sectional.

SETTING

Laboratory.

PARTICIPANTS

Sixty-six patients 6 months after ACLR participated.

INTERVENTIONS

Patients performed the SLSD, YB-A, and completed PROs after ACLR.

MAIN OUTCOME MEASURES

Patients completed the International Knee Documentation Committee Score (IKDC), the Lysholm Activity Scale, the Tampa Scale of Kinesiophobia (TSK-11), and the Knee Injury and Osteoarthritis Outcome Score (KOOS)-Symptom, -Sport, and -Quality of Life (QOL) subscales. The SLSD requires subjects to complete as many single-leg step-downs as possible in 60 seconds, and the YB-A involves reaching anteriorly on a single limb. Pearson product moment correlations were used to assess relationships between the YB-A and SLSD performance to each PRO.

RESULTS

Single-leg step-down test symmetry was significantly correlated with the TSK-11 (r = -0.70), KOOS-Sport (r = 0.40), -Symptom (r = 0.46), and -QOL (r = 0.42). The YB-A symmetry was significantly correlated with the KOOS-Symptom (r = 0.30) and KOOS-Sport (r = 0.30).

CONCLUSIONS

Single-leg step-down test performance demonstrated stronger relationships to patient-reported knee function than the YB-A. Furthermore, the SLSD symmetry was strongly correlated with fear of movement. The SLSD provides a robust method for clinicians to assess dynamic knee function and may aid in identifying patients who could benefit from intervention to reduce fear of movement or reinjury.

Measurement of Ankle Joint Movements Using IMUs during Running

Gait analysis has historically been implemented in laboratory settings only with expensive instruments; yet, recently, efforts to develop and integrate wearable sensors into clinical applications have been made. A limited number of previous studies have been conducted to validate inertial measurement units (IMUs) for measuring ankle joint kinematics, especially with small movement ranges. Therefore, the purpose of this study was to validate the ability of available IMUs to accurately measure the ankle joint angles by comparing the ankle joint angles measured using a wearable device with those obtained using a motion capture system during running. Ten healthy subjects participated in the study. The intraclass correlation coefficient (ICC) and standard error of measurement were calculated for reliability, whereas the Pearson coefficient correlation was performed for validity. The results showed that the day-to-day reliability was excellent (0.974 and 0.900 for sagittal and frontal plane, respectively), and the validity was good in both sagittal (r = 0.821, p < 0.001) and frontal (r = 0.835, p < 0.001) planes for ankle joints. In conclusion, we suggest that the developed device could be used as an alternative tool for the 3D motion capture system for assessing ankle joint kinematics.

Lack of Consensus on Return-to-Sport Criteria Following Lateral Ankle Sprain: A Systematic Review of Expert Opinions

CONTEXT

Lateral ankle sprains (LAS) have one of the highest recurrence rates of all musculoskeletal injuries. An emphasis on rapid return to sport (RTS) following LAS likely increases reinjury risk. Unfortunately, no set of objective RTS criteria exist for LAS, forcing practitioners to rely on their own opinion of when a patient is ready to RTS.

PURPOSE

To determine if there was consensus among published expert opinions that could help inform an initial set of RTS criteria for LAS that could be investigated in future research.

EVIDENCE ACQUISITION

PubMed, CINHL, and SPORTDiscus databases were searched from inception until October 2018 using a combination of keywords. Studies were included if they listed specific RTS criteria for LAS. No assessment of methodological quality was conducted because all included papers were expert opinion papers (level 5 evidence). Extracted data included the recommended domains (eg, range of motion, balance, sport-specific movement, etc) to be assessed, specific assessments for each listed domain, and thresholds (eg, 80% of the uninjured limb) to be used to determine RTS. Consensus and partial agreement were defined, a priori, as ≥75% and 50% to 75% agreement, respectively.

EVIDENCE SYNTHESIS

Eight domains were identified within 11 included studies. Consensus was reached regarding the need to assess sport-specific movement (n = 9, 90.9%). Partial agreement was reached for the need to assess static balance (n = 7, 63.6%). The domains of pain and swelling, patient reported outcomes, range of motion, and strength were also partially agreed on (n = 6, 54.5%). No agreement was reached on specific assessments of cutoff thresholds.

CONCLUSIONS

Given consensus and partial agreement results, RTS decisions following LAS should be based on sport-specific movement, static balance, patient reported outcomes, range of motion, and strength. Future research needs to determine assessments and cutoff thresholds within these domains to minimize recurrent LAS risk.

Short-Term Effects of Balance Training with Stroboscopic Vision for Patients with Chronic Ankle Instability: A Single-Blinded Randomized Controlled Trial

Chronic Ankle Instability (CAI) is one of the most common musculoskeletal dysfunctions. Stroboscopic vision (SV) training has been deemed to enhance somatosensorial pathways in this population group; nevertheless, until recently no studies have addressed the additional effects of this treatment option to the traditional therapeutic approach.

METHODS

To evaluate the effectiveness of a partial visual deprivation training protocol in patients with CAI, a randomized controlled trial was carried out. Patients with CAI (n = 73) were randomized into either a balance training, SV training, or a control (no training) group. For participants assigned into training groups, they received 18 training sessions over 6 weeks. The primary outcome was dynamic balance as measured by the Star Excursion Balance Test assessed at baseline and after 6 weeks of intervention. Secondary outcome measures included ankle dorsiflexion range of motion, self-reported instability feeling, and ankle functional status.

RESULTS

Better scores in stroboscopic training and balance training groups in all outcome measures were observed in comparison with the control group with moderate to large effect sizes. Stroboscopic training was more effective than neuromuscular training in self-reported instability feeling (cohen's d = 0.71; p = 0.042) and anterior reach distance of the star excursion balance test (cohen's d = 1.23; p = 0.001).

CONCLUSIONS

Preliminary findings from the effects of SV Stroboscopic training in patients with CAI, suggest that SV may be beneficial in CAI rehabilitation.

Effects of Plyometric and Balance Training on Neuromuscular Control of Recreational Athletes with Functional Ankle Instability: A Randomized Controlled Laboratory Study

Plyometric exercise has been suggested for knee injury prevention in sports participation, but studies on ankle plyometric training are limited. This study aims to investigate the change of joint position sense and neuromuscular activity of the unstable ankle after six-week integrated balance/plyometric training and six-week plyometric training. Thirty recreational athletes with functional ankle instability were allocated into three groups: plyometric group (P) vs. plyometric integrated with balance training group (BP) vs. control group (C). Ankle joint position sense, integrated electromyography (EMG), and balance adjusting time during medial single-leg drop-landing tasks were measured before and after the training period. Following the six-week period, both training groups exhibited a lower absolute error in plantar flexion (P group: pre: 3.79° ± 1.98°, post: 2.20° ± 1.31°, p = 0.016; BP group: pre: 4.10° ± 1.87°, post: 2.94° ± 1.01°, p = 0.045), and the integrated group showed a lower absolute error in inversion angles (pre 2.24° ± 1.44° and post 1.48° ± 0.93°, p = 0.022), and an increased integrated EMG of ankle plantar flexors before landing. The plyometric group exhibited a higher integrated EMG of the tibialis anterior before and after landing (pre: 102.88 ± 20.93, post: 119.29 ± 38.33, p = 0.009 in post-landing) and a shorter adjusting time of the plantar flexor following landing as compared to the pre-training condition (pre: 2.85 ± 1.15 s, post: 1.87 ± 0.97 s, p = 0.006). In conclusion, both programs improved ankle joint position sense and muscle activation of the ankle plantar flexors during single-leg drop landing. The plyometric group showed a reduced adjusting time of the ankle plantar flexor following the impact from drop landing.

Lower limb biomechanics in individuals with chronic ankle instability during gait: a case-control study

Background

Individuals with chronic ankle instability (CAI) exhibit many biomechanical changes to lower limbs during walking. However, only a few studies have investigated the differences in lower limb biomechanics of individuals with CAI compared to healthy controls using a comprehensive approach including kinematic, kinetic and electromyography (EMG) measures. Consequently, the theoretical framework explaining the biomechanical adaptations in individuals with CAI is mostly based on the results of studies including heterogenous methods and participants’ specificities (e.g., level of disability). More studies using a comprehensive approach are needed to better understand the biomechanical adaptations associated with CAI. The objective of this case-control study was to identify the kinematic, kinetic and EMG differences between individuals with CAI and healthy controls during walking.

Methods

Twenty-eight individuals with CAI and 26 healthy controls were recruited to walk at a self-selected speed during which lower limb kinematics, kinetics and EMG were analysed. Ankle and knee angles and moments as well as gluteus medius, vastus lateralis, gastrocnemius lateralis, peroneus longus and tibialis anterior muscles activity were compared between the CAI and control groups using one-dimensional statistical parametric mapping.

Results

The CAI group exhibited greater ankle inversion angles from 14 to 48% of the stance phase (%SP) (p = 0.008), ankle eversion moments from 40 to 78%SP (p < 0.001), knee abduction moments from 3 to 6%SP and peroneus longus muscle activity from 0 to 15%SP (p = 0.003) and 60 to 76%SP (p = 0.003) compared to the control group. No significant between-group differences in ankle sagittal and transverse angles and moments, knee angles, knee sagittal and transverse moments as well as gluteus medius, vastus lateralis, gastrocnemius lateralis and tibialis anterior muscles activity were found.

Conclusions

During the first half of the stance phase, individuals with CAI could be at more risk of sustaining recurrent LAS mostly due to greater ankle inversion angles. However, the greater ankle eversion moments and peroneus longus muscle activity during the second half of the stance phase were an efficient mechanism to correct this maladaptive gait pattern and allowed to attenuate the faulty ankle movements during the pre-swing phase.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-021-00476-6.

Does verbal encouragement change dynamic balance? The effect of verbal encouragement on Star Excursion Balance Test performance in chronic ankle Instability

BACKGROUND

The Star Excursion Balance Test (SEBT) is commonly used for testing dynamic balance in chronic ankle instability (CAI) in both clinical and research settings. However, the effect of verbal encouragement (VE) on the SEBT performance is not known.

OBJECTIVE

To investigate the effects of VE on maximum reach distance performance between CAI and healthy participants on the SEBT.

METHOD

Thirty-four college-aged adults, 17 with CAI and 17 healthy controls, performed the SEBT in the anterior, posteromedial, and posterolateral reach directions. Independent variables (VE versus No-VE) and group (CAI versus healthy) were analyzed using Analysis of Variance (ANOVA) to determine whether VE and group affected reach performance.

RESULTS

There was a significant group-by-condition interaction (p = 0.02) for the anterior as well as for the posteromedial reach (p = 0.04). There was no statistically significant interaction (p = 0.48) for the posterolateral reach. There were moderate to large effect sizes in the reach distances found in the No-VE condition between the CAI and healthy controls, but with VE, the range of effect sizes from No-VE to VE were diminished.

CONCLUSION

There was a significant group by condition interaction for anterior and posteromedial reaches which shows that providing VE resulted in a greater increase in performance for participants with CAI compared to healthy controls. Psychological constraints need to be considered while performing and interpreting the results of the SEBT.

Submaximal Force Steadiness and Accuracy in Patients With Chronic Ankle Instability

CONTEXT

Patients with chronic ankle instability (CAI) have demonstrated sensorimotor impairments. Submaximal force steadiness and accuracy measure sensory, motor, and visual function via a feedback mechanism, which helps researchers and clinicians comprehend the sensorimotor deficits associated with CAI.

OBJECTIVE

To determine if participants with CAI experienced deficits in hip and ankle submaximal force steadiness and accuracy compared with healthy control participants.

DESIGN

Case-control study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty-one patients with CAI and 21 uninjured individuals.

MAIN OUTCOME MEASURE(S)

Maximal voluntary isometric contraction (MVIC) and force steadiness and accuracy (10% and 30% of MVIC) of the ankle evertors and invertors and hip abductors were assessed using the central 10 seconds (20%-87% of the total time) of the 3 trials.

RESULTS

Relative to the control group, the CAI group demonstrated less accuracy of the invertors (P < .001). Across all motions, the CAI group showed less steadiness (P < .001) and less accuracy (P < .01) than the control group at 10% of MVIC. For MVIC, the CAI group displayed less force output in hip abduction than the uninjured group (P < .0001).

CONCLUSIONS

Patients with CAI were unable to control ongoing fine force (10% and 30% of MVIC) through a feedback mechanism during an active test. These findings suggested that deficits in sensorimotor control predisposed patients with CAI to injury positions because they had difficulty integrating the peripheral information and correcting their movements in relation to visual information.

Effect of finding-oriented manual therapy techniques on muscle activity and postural control in patients with chronic ankle instability - A randomized controlled feasibility study

INTRODUCTION

Previous studies have analyzed the effects of manual therapy techniques (MTT) in patients with chronic ankle instability (CAI). Clinicians treat patients according the finding-oriented MTT approach. This approach is seldom pursued in research. The purpose of this study was to evaluate the feasibility and efficacy of finding-oriented MTT applications in patients with CAI.

METHOD

In this randomized controlled, blinded assessor crossover feasibility trial, participants were randomized to receive nine finding-oriented MTT treatments or no treatment during a three-week period, followed by a six-day washout period after which participants were crossed-over. Criteria under evaluation were adherence and attrition rates, safety (adverse events (AEs)) and acceptability and preliminary effects of finding-oriented MTT on muscular activity (measured by surface Electromyography (sEMG)) and on dynamic balance (measured by time to stabilization (TTS) and the modified Star Excursion Balance Test (modified STBT)).

RESULTS

Seven women and two men (mean age: 26 ± 6.1 years) with CAI enrolled in this feasibility study. Success criteria showed a high adherence (90%) and low attrition rate (10%). All data could be used for analysis. AEs such as tingling in the foot during a short time frame were reported after four finding-oriented MTT interventions. Preliminary effect sizes showed divergence and few statistically significant results for sEMG.

CONCLUSION

The participants were adherent to the finding-oriented MTT intervention. The acceptability of data recording and data analysis was good. In addition, the study protocol should be adapted by adding a 10-min warm up period, a participant familiarization to TTS and modified STBT, and test repetitions.

Eyes-Open Versus Eyes-Closed Somatosensory Motor Balance in Professional Soccer Players With Chronic Ankle Instability: A Case-Control Study

Background:

Chronic ankle instability (CAI) is a condition defined by certain structural and functional deficits in the ankle joint complex after acute ankle injury. These deficits include pathological joint laxity, impaired postural control, and decreased strength and neuromuscular control.

Purpose:

To compare an eyes-open versus an eyes-closed balance training protocol in professional soccer players with CAI.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

For this study, we evaluated 19 players from 2 professional soccer teams in Madrid, Spain, all of whom had CAI. Participants from both teams were randomly assigned to an eyes-open group (n = 9) or eyes-closed group (n = 10). All participants completed 4 weeks of a supervised exercise protocol consisting of 3 sessions per week. Members of both the eyes-open and eyes-closed groups performed the same exercise protocol in the same order of execution. At the end of the protocol, the participants were assessed for pain (visual analog scale), ankle dorsiflexion range of motion (weightbearing lunge test), dynamic stability (Star Excursion Balance Test), and fear of movement and reinjury (Tampa Scale for Kinesiophobia). We compared results both before and after balance training and between the eyes-open and eyes-closed balance training groups.

Results:

Statistically significant differences were found for all of the assessed variables before and after balance training. No statistically significant differences were found between the eyes-closed and eyes-open groups on any variable.

Conclusion:

In the current study, eyes-closed balance training was not more effective than eyes-open balance training for CAI in professional soccer players.

Cross-education effect of balance training program in patients with chronic ankle instability: A randomized controlled trial

Chronic ankle instability (CAI) is frequently developed due to failure of the functional rehabilitation after acute ankle sprain. So, there is a need for an alternative way by which we can begin neuro-muscular control retraining sooner.

PURPOSE

This study was conducted to examine the effect of 6-week Single-limb Balance Training Program of the non-affected side on the Overall Stability Index (OASI), Antero-Posterior Stability Index (APSI), and the Medio-Lateral Stability Index (MLSI) of the affected side in females with unilateral CAI.

METHODS

Thirty-two female patients with CAI with mean age 20.96 ± 1.69 years participated in this study. They were randomly assigned into three groups: experimental group A (Cross-Education) (n = 11) performed the exercises for the non-affected side, experimental group B (Traditional Training) (n = 11) performed the exercises for the affected side, and Control group C (n = 10) did not perform any exercises. The randomization was done using statistical random tables. Data were collected using the Biodex Balance system before and after training.

RESULTS

Two-way mixed design MANOVA revealed that there were significant improvements in the mean values of the OASI, APSI and MLSI after training (p < .05) in both the Cross-Education group (A) and Traditional Training group (B) with no significant difference in-between for the OASI, MLSI and APSI after training. There was no significant difference (p > .05) between the pre and post-training mean values of the OASI, MLSI and APSI in the Control group (C).

CONCLUSION

Single-limb balance training for the non-affected side is effective in improving the postural control of the affected side in patients with CAI.

Effects of Nonelastic Taping and Dual Task on Kinematics and Kinetics of the Ankle Joint

Objectives

The purpose of this experimental study was to investigate the effects of nonelastic taping and dual task on ankle kinematics and kinetics in gait analysis of healthy adults.

Methods

A total of 21 healthy adults completed trials of gait analysis using a Vicon system combining ground walking with different cognitive task conditions (none, modified Stroop color/character naming, and serial-7 subtraction), with or without nonelastic taping. Ankle kinematics and kinetics including speed, ankle plantarflexion and inversion angle, ground reaction force (GRF), and stride time variability (STV) under all conditions of taping (YES or NO) and cognitive task (none, naming, and subtraction) were characterized and analyzed with repeated-measures ANOVA.

Results

As regards cognitive performance, the serial-7 subtraction performance under walking conditions with and without taping was significantly poorer than simple sitting condition (P < 0.001). For kinematics and kinetics, STV showed statistically significant decrease (P=0.02) when subjects underwent taping application. Vertical GRF was significantly greater under taping than barefoot (P=0.001). Ankle plantarflexion at initial contact (IC) under the dual-task walking was significantly more than under simple walking (P=0.008).

Conclusions

Applications of nonelastic taping and dual task may lead to the STV, vertical GRF, ankle plantarflexion, and speed alterations because of restricted joint range of motion and changed sensorimotor neural circuit. When healthy adults performed dual-task walking, central neural resources allocation was disturbed, leading to weakened performance in both motor and cognitive tasks.

Ankle inversion proprioception measured during landing in individuals with and without chronic ankle instability

BACKGROUND

Research evidence has suggested that a more sensitive ankle proprioceptive testing method with higher ecological validity is needed for assessing proprioceptive deficits in individuals with chronic ankle instability (CAI).

OBJECTIVES

(1) To determine the test-retest reliability of a novel ankle proprioception assessment tool, the Ankle Inversion Discrimination Apparatus for Landing (AIDAL); (2) To assess whether AIDAL scores were sufficiently sensitive to detect proprioceptive deficits in chronic ankle instability (CAI); and (3) To examine whether AIDAL scores correlated with Cumberland Ankle Instability Tool (CAIT) scores.

DESIGN

Cross-sectional study.

METHODS

The AIDAL was purpose-built to assess ankle discrimination in four positions of ankle inversion (10°, 12°, 14° and 16°) upon landing from a 10cm drop. Area Under the Receiver Operating Curve (AUC) was employed as the ankle proprioceptive discrimination score. Seven-day test-retest reliability was evaluated with 23 university students (12 CAI and 11 non-CAI), and another 36 university students (18 CAI and 18 non-CAI) were in the comparison study.

RESULTS

The test-retest reliability ICC score for the whole group was 0.763 (95% CI=0.519-0.892), which showed an excellent reliability level. ICC _(3,1) was 0.701 for the non-CAI group (95%CI=0.210-0.910) and 0.804 for the CAI group (95%CI=0.451-0.939). The CAI group performed at a significantly lower level on the AIDAL assessment than the non-CAI group (0.777±0.05 vs. 0.815±0.05, F=5.107, p=0.03). The discriminative AUC value for the AIDAL test was 0.756 with a cut point of 0.819 (sensitivity=0.733, specificity=0.800). The MDC₉₀ scores for CAI and non-CAI groups were both 0.04. Spearman's correlation showed that the CAIT scores were significantly correlated with the ankle proprioceptive discrimination scores (rho=0.401, p=0.015).

CONCLUSION

The AIDAL showed good test-retest reliability for both non-CAI and CAI groups. Measuring ankle inversion proprioception during landing may be important for assessing the outcomes of CAI rehabilitation, as proprioceptive performance obtained from the AIDAL was significantly correlated with severity of functional ankle instability CAIT scores.

Effects of Dry Needling on Neuromuscular Control of Ankle Stabilizer Muscles and Center of Pressure Displacement in Basketball Players with Chronic Ankle Instability: A Single-Blinded Randomized Controlled Trial

This study aimed to compare the effects of dry needling (DN) versus placebo DN applied to the peroneus longus (PL) and tibialis anterior (TA) on neuromuscular control and static postural control in basketball players with chronic ankle instability (CAI). A single-blinded randomized controlled trial was conducted. Thirty-two male and female basketball players with CAI were randomly assigned to receive either DN (n = 16) or placebo DN (n = 16). Pre-activation amplitudes of PL and TA were assessed with surface electromyography (EMG) during a dynamic landing test. Center of pressure (CoP) displacement and sway variability in anterior-posterior (AP) and medio-lateral (ML) directions were measured with a force platform during a single leg balance test (SLBT). Measures were obtained prior to a single DN intervention, immediately after, at 48 h, and 1 month after. The DN group displayed a significant increase in PL and TA pre-activation values, which were maintained 1 month later. Significant reductions in the ML and AP displacements and sway variability of CoP were found for the DN group. These results showed improvements in feedback/feed-forward strategies following DN, including enhanced neuromuscular control and static postural control, with the potential to become a convenient and accessible preventive treatment in CAI subjects.

The effects of Kinesiology Tape on static postural control in individuals with functional ankle instability

OBJECTIVE

To investigate if applying Kinesiology Tape (KT) on the unstable ankle may improve static postural control in individuals with Functional ankle instability.

DESIGN

A repeated measured study. Participants performed a series of static quiet bipedal and unipedal stances on a force platform. Measurements were taken at three different times: baseline or no tape, immediately and 24 h after the taping application with the tape remaining on the ankle.

SETTING

A university's psychomotor laboratory.

PARTICIPANTS

Twenty young adults with Functional ankle instability aged from 18 to 30 years old.

OUTCOME MEASURES

Postural control was assessed by four measures derived from the centre of pressure data: Area of 95% Confidence ellipse, standard deviation of displacements, mean velocity and mean power frequency. The analysis of variance (ANOVA) was performed to determine any significant improvement in postural control over time due to KT.

RESULTS

Only minor changes in mean velocity and MPF in unipedal stances were observed immediately after KT application. However, the overall results indicated statistically insignificant improvements in postural control neither immediately after KT application nor after 24 h.

CONCLUSION

Results suggest that the use of KT did not affect bipedal and unipedal stances of individuals with functional ankle instability.

Joint Coordination and Stiffness During Landing in Individuals With Chronic Ankle Instability

The purpose of the present study was to examine the effect of chronic ankle instability (CAI) on lower-extremity joint coordination and stiffness during landing. A total of 21 female participants with CAI and 21 pair-matched healthy controls participated in the study. Lower-extremity joint kinematics were collected using a 7-camera motion capture system, and ground reaction forces were collected using 2 force plates during drop landings. Coupling angles were computed based on the vector coding method to assess joint coordination. Coupling angles were compared between the CAI and control groups using circular Watson-Williams tests. Joint stiffness was compared between the groups using independent t tests. Participants with CAI exhibited strategies involving altered joint coordination including a knee flexion dominant pattern during 30% and 70% of their landing phase and a more in-phase motion pattern between the knee and hip joints during 30% and 40% and 90% and 100% of the landing phase. In addition, increased ankle inversion and knee flexion stiffness were observed in the CAI group. These altered joint coordination and stiffness could be considered as a protective strategy utilized to effectively absorb energy, stabilize the body and ankle, and prevent excessive ankle inversion. However, this strategy could result in greater mechanical demands on the knee joint.

Lower-Extremity Motor Synergies in Individuals With and Without Chronic Ankle Instability

Current theoretical models suggest that ankle sprain copers exhibit movement adaptations contributing to the avoidance of chronic ankle instability. However, few studies have examined adaptations at the level of biomechanical motor synergies. The purpose was to examine characteristics of the support moment synergy between individuals with chronic ankle instability, copers, and healthy individuals. A total of 48 individuals participated in the study. Lower-extremity kinetics and variability in the moment of force patterns were assessed during the stance phase of walking trials. The copers exhibited reductions in the support moment during the load response and preswing phase compared with the chronic ankle instability group, as well as during the terminal stance and preswing phase compared the healthy group. The copers also exhibited reductions in the hip extensor moment and ankle plantarflexion moment compared with healthy and chronic ankle instability groups during intervals of stance phase. Variability of the support moment and knee moment was greater in the copers compared with the chronic ankle instability group. Dampening of the support moment and select joint moments exhibited by the copers may indicate an adaptive mechanism to mitigate loading perturbations on the previously injured ankle. Heightened motor variability in copers may be indicative of a more adaptable motor synergy compared with individuals with chronic ankle instability.

Effect of Dry Needling on Spinal Reflex Excitability and Postural Control in Individuals With Chronic Ankle Instability

OBJECTIVE

The purpose of this study was to compare postural control and neurophysiologic components of balance after dry needling of the fibularis longus between individuals with chronic ankle instability (CAI) and a healthy control group.

METHODS

This quasi-experimental university-laboratory study included 50 adult volunteers-25 with CAI (16 female, 9 male; age: 26 ± 9.42 years; height: 173.12 ± 9.85 cm; weight: 79.27 ± 18 kg) and 25 healthy controls (15 female, 10 male; age: 25.8 ± 5.45 years; height: 169.47 ± 9.43 cm; weight: 68.47 ± 13 kg). Participants completed the Star Excursion Balance Test (SEBT), single-leg balance, and assessment of spinal reflex excitability before and after a single treatment of dry needling to the fibularis longus. The anterior, posterolateral, and posteromedial directions of the SEBT were randomized, and reach distances were normalized to a percentage of leg length. A composite SEBT score was calculated by averaging the normalized scores. Postural control was assessed in single-limb stance on a force plate through time-to-boundary measurements in eyes-open and eyes-closed conditions. Fibularis longus and soleus spinal reflexes were obtained by providing electrical stimulation to the common fibular and tibial nerves with participants lying prone. A Group × Time analysis examined changes in performance, and effect sizes were calculated to assess significance.

RESULTS

Significant group × time interactions were identified for composite (P = .006) and posteromedial (P = .017) SEBT scores. Significant time effects for all directions of the SEBT, time to boundary with eyes open, and the mediolateral direction with eyes closed indicate improved postural control following treatment (P < .008). Within-group effect sizes for significant time effects ranged from small to large, indicating potential clinical utility.

CONCLUSION

Dry needling demonstrated immediate short-term improvement in measures of static and postural control in individuals with CAI as well as healthy controls.

Assessments of Sensorimotor Deficits Used in Randomized Clinical Trials With Individuals With Ankle Sprains and Chronic Ankle Instability: A Scoping Review

The main purpose of this scoping review was to summarize the most common tasks and outcome measures in randomized control trials (RCTs) used to assess sensorimotor function following ankle sprain and chronic ankle instability (CAI). We also aimed to summarize the description of inclusion criteria used in articles. We searched for RCTs published between 2008 and 2018 using the following databases: MEDLINE, PubMed, SPORTDiscus, and Web of Science. Eligible studies included participants of either sex who had had at least one ankle sprain with/without subsequent CAI. All articles assessed sensorimotor function. The tasks, outcome measures, and inclusion criteria were categorized, and frequencies of use in each category were calculated. Of 272 publications, 31 met the eligibility criteria. The most common task was single-limb stance (58% of 31). The most common outcome measure was the posterior-medial reach distance of the Star Excursion Balance Test (SEBT) (13 of 16 articles, 81%). Different inclusion criteria for a history of ankle sprains or CAI were used. A wide range of sensorimotor assessments and inclusion criteria was used among studies involving individuals with a history of ankle sprain with or without CAI, which could make it difficult to compare and generalize study results. This scoping review provides a baseline for planning future studies exploring outcome measures to assess sensorimotor function of individuals with a history of ankle sprain with or without CAI.

Gait and plantar sensation changes following massage and textured insole application in patients after anterior cruciate ligament reconstruction

BACKGROUND

Gait impairments following anterior cruciate ligament reconstruction (ACLR) may contribute to reinjury or future osteoarthritis development. Recently, plantar cutaneous sensation deficits have been reported post-ACLR. These sensory deficits may influence gait and represent a mechanism through which to improve gait.

RESEARCH QUESTION

Can established sensory interventions change sensation and gait in patients after ACLR and compared to healthy adults?

METHODS

Twenty-two adults (n = 11 post-ACLR, age:20.5 ± 1.9years, body mass index[BMI]:24.5 ± 3.6 kg/m²; n = 11 healthy, age:20.7 ± 1.4years, BMI:23.3 ± 2.7 kg/m²) completed two sessions separated by 48 h. Gait and plantar cutaneous sensation were assessed pre- and post-intervention (massage or textured insoles). Gait analysis was completed using 3D motion capture at 1.4 m/s ± 5% and standard inverse dynamics analysis. Plantar cutaneous sensation was assessed using Semmes Weinstein Monofilaments with a 4-2-1 stepping algorithm at the plantar aspect of the first metatarsal head, base of the fifth metatarsal, and lateral and medial malleoli. Plantar massage was a 5-minute massage to both feet. Textured insoles (coarse grit sandpaper) were worn while walking. Biomechanical data were assessed via mixed-models, repeated measures ANOVAs and 90 % confidence intervals. Wilcoxon Signed Rank tests and Mann-Whitney U tests evaluated plantar cutaneous sensation within and between groups, respectively.

RESULTS

Knee adduction moment was lower in the ACLR versus the contralateral limb pre-massage. The vGRF was lower during the first half of stance but greater during the second half of stance in the ACLR versus the control group post-massage. Massage improved ACLR limb sensation over the first metatarsal head (P = 0.042) and medial malleolus (P = 0.027). Textured insole application improved ACLR limb sensation over the first (P = 0.043) and fifth (P = 0.027) metatarsals and medial malleolus (P = 0.028).

SIGNIFICANCE

Plantar massage and textured insoles improved plantar cutaneous sensation in the ACLR limb. Neither intervention influenced gait. Improving plantar sensation may be beneficial for patients after ACLR; however, sensory interventions to improve gait are necessary.

Walking Gait Mechanics and Gaze Fixation in Individuals With Chronic Ankle Instability

CONTEXT

Many individuals who suffer a lateral ankle sprain will develop chronic ankle instability (CAI). Individuals with CAI demonstrate kinematic differences in walking gait, as well as somatosensory alterations compared with healthy individuals. However, the role of vision during walking gait in this population remains unclear.

OBJECTIVE

To evaluate ankle kinematics, gaze deviations, and gaze velocity between participants with CAI and healthy controls while walking on a treadmill during 3 separate visual conditions (no target, fixed target, and moving target).

DESIGN

Case-control study.

SETTING

Laboratory. Patients (or Other Participants): Ten CAI participants and 10 healthy matched controls participated.

MAIN OUTCOME MEASURES

Ankle sagittal and frontal plane kinematics were analyzed for the entire gait cycle. Average and standard deviation (SD) for gaze deviation and gaze velocity were calculated in the horizontal (X) and vertical (Y) planes.

RESULTS

No significant differences were found between groups for either ankle kinematics or gaze variables; however, large effect sizes were found in the no target condition for average deviation of X (healthy 0.05 [0.02], CAI 0.12 [0.11]). Moderate effect sizes were identified in the no target condition for SD of Y (healthy 0.04 [0.03], CAI 0.11 [0.15]) and the moving target condition for average velocity of X (healthy 1.56 [0.73], CAI 2.27 [1.15]) and Y (healthy 1.07 [0.51], CAI 1.47 [0.52]).

CONCLUSIONS

Although no significant differences were found between groups, it is possible that the role of vision in individuals with CAI may be altered with a more difficult task.

Performance Differences Between the Modified Star Excursion Balance Test and the Y-Balance Test in Individuals With Chronic Ankle Instability

CONTEXT

The modified Star Excursion Balance Test (mSEBT) and Y-Balance Test (YBT) are common dynamic postural stability assessments for individuals with chronic ankle instability (CAI). However, the reach distance measurement technique and movement strategy used during the mSEBT and YBT differ. To date, no studies have compared task performance differences on these tests in CAI patients.

OBJECTIVE

To determine whether individuals with CAI perform the mSEBT and YBT differently.

DESIGN

Cross-sectional.

SETTING

Biomechanics laboratory.

PARTICIPANTS

Of 97 consented participants, 86 (43 females, 43 males; age 21.5 [3.3] y, height 169.8 [10.3] cm, mass 69.5 [13.4] kg), who reported ≤25 on the Cumberland Ankle Instability Tool, ≥11 on the Identification of Functional Ankle Instability, and had a history of a moderate to severe ankle sprain(s) participated.

INTERVENTIONS

Participants were instructed to perform the mSEBT and YBT in a predetermined counterbalanced order. Three anterior, posteromedial, and posterolateral trials of each test were completed on the involved limb after 4 practice trials. Test direction order was randomized for each participant.

MAIN OUTCOME MEASURES

Normalized (expressed in percentage) reach distance in each direction. Paired sample t tests were performed to compare each of the 3 directions between the mSEBT and YBT.

RESULTS

Significantly shorter reach distances in the anterior (58.9% [5.8%] vs 61.4% [5.4%], P = .001) and the posteromedial (98.8% [8.6%] vs 100.8% [8.1%], P = .003) directions were noted on the mSEBT relative to the YBT. No differences in the posterolateral directions were observed.

CONCLUSIONS

Within those with CAI, mSEBT and YBT normalized reach distances differ in the anterior and posteriomedial directions. As a result, clinicians and researchers should not directly compare the results of these tests.

Muscle activation patterns during backward walking in people with chronic ankle instability

Background

Altered walking patterns are often described in individuals with chronic ankle instability (CAI). Contemporary treatment paradigms recommend backward walking (BW) to improve locomotion in people with musculoskeletal disorders. The purpose of this study was to determine whether muscle activity and activation variability during BW differs between subjects with and without CAI.

Methods

Sixteen participants with CAI and 16 healthy controls walked on a treadmill at their self-selected speed under BW and forward walking (FW) conditions. Surface electromyography (EMG) data for the peroneus longus, tibialis anterior, medial gastrocnemius and gluteus medius muscles were collected. EMG amplitude normalized to maximum voluntary isometric contraction (%MVIC) and the standard deviation (SD) of the %MVIC EMG amplitude was calculated throughout the gait cycle. In addition, the area under the curve (AUC) of the %MVIC EMG amplitude was calculated before and after initial contact (pre-IC: 90–100% of stride; post-IC: 0–10% of stride).

Results

No differences between groups were noted in the %MVIC amplitude or activation variability (SD of %MVIC EMG) under BW or FW. In both groups, decreased tibialis anterior (p < 0.001) and gluteus medius (p = 0.01), and increased medial gastrocnemius (p < 0.001) activation were observed during pre- and post-IC under BW condition.

Conclusion

Participants with CAI and healthy controls have similar muscle activity patterns during BW. Yet, the results should be interpreted with caution due to the heterogeneity of the CAI population.

Center of pressure excursion and muscle activation during gait initiation in individuals with and without chronic ankle instability

The aim of the current study was to determine differences in center of pressure (COP)excursion and muscle activation during gait initiation (GI) in those with and without chronic ankle instability (CAI). Thirty-four participants, 17 per group, volunteered to participate. Participants were asked to stand barefoot on a force plate before initiating gait upon hearing an auditory cue. Reaction time, anticipatory postural adjustment phase time, as well as normalized peak COP excursion during the anticipatory postural adjustment phase was calculated. Response time of Soleus and Tibialis Anterior muscles were concurrently recorded via electromyography. The results demonstrate a longer reaction time and shorter anticipatory postural adjustment phase time in the CAI group (p < 0.05). No significant between group differences in peak normalized COP excursion were noted (p > 0.05). Muscle onset patterns differed between groups as those with CAI demonstrated earlier Soleus activation compared to the control group (p < 0.05). The results suggest that those with CAI have an altered GI motor control strategy as evidenced by reduced or absent Soleus muscle inhibition during APA phase of GI relative to controls. The APA phase is controlled by the secondary motor area, therefore, the presence of motor control alterations in CAI patients may be due to a supra-spinal alterations.

Spatiotemporal gait characteristics and ankle kinematics of backward walking in people with chronic ankle instability

Backward walking offers a unique challenge to balance and ambulation. This study investigated the characteristics of spatiotemporal gait factors and ankle kinematics during backward walking in people with chronic ankle instability. Sixteen subjects with chronic ankle instability and 16 able-bodied controls walked on a treadmill at their self-selected speed under backward and forward walking conditions. Gait speed, cadence, double limb support percentage, stride time variability, and three-dimensional ankle kinematics were compared between groups and conditions. During backward walking, both groups had significantly slower gait speed, lower cadence, and greater stride time variability. In addition, under backward walking condition, subjects in both groups demonstrated significant sagittal and frontal kinematic alternations, such as greater dorsiflexion and inversion following initial contact (0–27.7%, 0–25.0% of gait cycle respectively, p < 0.001). However, there were no significant differences between groups in any of the measured outcomes. This indicates that subjects with chronic ankle instability adapt to self-selected speed backward walking similarly to healthy controls. Assessments with more challenging tasks, such as backward walking with dual task and backward walking at fast speed, may be more appropriate for testing gait impairments related to chronic ankle instability.

Systematic review of motor control and somatosensation assessment tests for the ankle

Background/Aim

Ankle sprains are frequent musculoskeletal injuries that can lead to sensorimotor deficits provoking long-term instability at the ankle joint. A broad variety of clinical tests currently exist to assess sensorimotor processing, and are commonly clinically referred to as proprioceptive tests. However, there is a discrepancy in the use of the term proprioception when looking at the main outcome of these tests. As identifying specific deficits is important for motor recovery, it is critical for clinicians to select the most appropriate tests.

Methods

A systematic review of four databases was performed to provide an up-to-date review of the psychometric properties of available tests referred to as proprioceptive tests. Seventy-nine articles on eight ankle proprioceptive tests were included and critically appraised. Data on validity, reliability and responsiveness were extracted from the included articles and synthesised. The tests reviewed were then divided into two categories based on their main outcome: motor control or somatosensation.

Results

Strong evidence showed that the Star Excursion Balance Test, a motor control test, is capable of differentiating between stable and unstable ankles. Moderate evidence suggests that somatosensation tests, such as Joint Position Sense, are also valid and reliable, but their responsiveness has yet to be evaluated.

Conclusions

Together, these findings indicate that the Star Excursion Balance Test can be used in the clinic to assess motor control based on its excellent psychometric properties. However, as ankle stability control involves complex sensorimotor interactions, care has to be taken regarding the use of this test as a specific tool for proprioception assessment.

Acute Effects of Increased Joint Mobilization Treatment Duration on Ankle Function and Dynamic Postural Control in Female Athletes With Chronic Ankle Instability

Background:

Chronic ankle instability (CAI) is linked to mechanical and functional insufficiencies. Joint mobilization is purported to be effective at treating these deficits.

Purpose:

To examine the effect of different treatment durations of a grade IV anterior-to-posterior ankle joint mobilization on weightbearing dorsiflexion range of motion (WB-DFROM), posterior talar glide (PG), and dynamic postural control in individuals with CAI.

Study Design:

Controlled laboratory study.

Methods:

A total of 48 female athletes (mean age, 22.8 ± 4.8 years) with unilateral CAI participated in this study. Participants were randomly assigned to 1 of 3 treatment conditions: 30 seconds, 60 seconds, and 120 seconds. Treatment was provided to the injured limb on 3 separate occasions 48 hours apart and consisted of a Maitland grade IV anterior-to-posterior talar joint mobilization based on the participant’s initial group assignment. WB-DFROM; PG; and the anterior (ANT), posteromedial (PM), and posterolateral (PL) reach directions of the Star Excursion Balance Test were measured bilaterally before and after each treatment. The uninjured limb acted as a control. Data were analyzed using 2-way mixed-model analyses of variance, and effect sizes were calculated through use of Hedges g.

Results:

Significant differences were detected after all treatment sessions for all outcome measures (P ≤ .001) and between treatment groups after sessions 1, 2, and 3 for all outcome measures (P ≤ .001). Effect sizes were very large or huge for all treatment groups for WB-DFROM, PG, and ANT reach direction. Substantial variation was found in effect sizes for PM and PL measures.

Conclusion:

Accessory mobilization is an effective treatment to induce acute changes in ankle motion and dynamic postural control in patients with CAI, with longer treatment durations conferring greater improvements.

Clinical Relevance:

This study adds clarity to the use of joint mobilization treatments and will add to the current clinical practice strategy for patients with CAI.

The Effects of Blood Flow Restriction on Muscle Activation and Hypoxia in Individuals With Chronic Ankle Instability

CONTEXT

Muscle dysfunction is common in patients with chronic ankle instability (CAI). Blood flow restriction (BFR) may enhance muscle responses during exercise and provide an opportunity to enhance muscle adaptations to ankle rehabilitation exercises; however, there is no evidence examining the effect of BFR on muscle function in CAI patients.

OBJECTIVE

Examine the effects of BFR on muscle activation and oxygen saturation during submaximal ankle eversion and dorsiflexion exercises in individuals with CAI.

DESIGN

Cross-over study design.

SETTING

Laboratory setting. Patients (or Other Participants): Nineteen young adults with a history of CAI.

INTERVENTIONS

Participants performed 4 sets (30, 15, 15, and 15) of eversion and dorsiflexion resistance exercises at 30% of maximum voluntary isometric contraction during 2 conditions, BFR and control. For BFR, a cuff was applied above the knee at 80% of blood flow occlusion. For control, the cuff was not inflated.

MAIN OUTCOME MEASURES

Fibularis longus and tibialis anterior electromyography muscle activation, lower-leg muscle oxygen saturation, and ratings of perceived exertion were recorded during exercises.

RESULTS

Average grand mean muscle activation was 5.6% greater during eversion (P = .03) and 7.7% greater during dorsiflexion (P = .01) resistance exercises with BFR compared with control; however, the magnitudes of the effects of BFR were only clinically important during the dorsiflexion exercises. Lower-leg muscle oxygen saturation was 31% to 44% lower (P < .001) during BFR exercises. Ratings of perceived exertion were significantly higher during BFR exercises (P < .001).

CONCLUSIONS

Greater muscle activation and hypoxia were present during submaximal resistance exercise with BFR in participants with CAI. Greater muscle activation and hypoxia during BFR exercises may be important acute responses mediating the training-related muscle adaptations that have been observed with BFR. The presence of these acute responses in CAI patients supports further research examining BFR as a potential ankle rehabilitation tool.

Minimal detectable change and reliability of the star excursion balance test in patients with lateral ankle sprain

OBJECTIVE

Lateral ankle sprain (LAS) is one of the most prevalent musculoskeletal injuries in the general population and athletes. Dynamic postural control deficits and somatosensory alterations are common signs after an episode of LAS. It is important to detect these deficits to prevent a recurrent sprain and the development of chronic ankle instability. The Star Excursion Balance Test (SEBT) is a tool used to assess dynamic postural control in patients with LAS. SEBT test-retest reliability has been evaluated in several populations. However, no data on patients with LAS are available and we do not know the minimal detectable change (MDC). The primary objective of our study was to obtain the MDC for normalized reach distances of the eight SEBT directions in patients with LAS. The secondary objective was to determine test-retest reliability.

METHODS

Cross-sectional study. Thirty-one patients (between 18 and 40 years old) diagnosed with a Grade I or II LAS. Participants were evaluated by two raters at two time-points separated by an interval of 24-72 hrs. In each assessment, four practice trials were allowed, then three test trials were performed in a randomized order. Normalized reaching distances were analyzed.

RESULTS

From the initial 31 patients, two were eliminated, so 29 patients were considered for the final analysis. The MDC values obtained were 6.73-13.36%, and the medial and posteromedial directions showed the lowest and highest values, respectively. A statistically significant increase was found in lateral direction between T0 and T1. Intraclass correlation coefficients ranged from 0.72 to 0.93.

CONCLUSION

The SEBT is an accurate and reliable tool to assess dynamic postural control in patients with LAS.

An intervention based on the health belief model led to improvements in self-efficacy towards ERIPP participation and functional performance in club sport athletes: a pilot study

OBJECTIVES

To determine if an intervention based on the Health Belief Model (HBM) could improve attitudes towards exercise-related injury prevention program (ERIPP) participation and functional performance in club sport participants.

DESIGN

Repeated measures METHODS: Participants completed the HBM Scale (HBMS) and Theory of Planned Behavior Scale (TPBS) to assess attitudes towards ERIPP participation at three time points (pre-measure, post-measure, follow-up measure). The HBM based intervention was delivered immediately following the pre-measure containing: 1) education on ERIPPs, benefits and barriers to participating, strategies to overcome barriers, risk factors and consequences for lower extremity injuries, and strategies to prevent lower extremity injuries 2) individualized feedback on functional performance 3) demonstration and participation in the 11+. Attitudes towards injury prevention were compared using the subscales of the HBMS and TPBS at all three time points. Functional performance was compared at the pre-measure and follow-up measure.

RESULTS

Significant improvements with large effect sizes were detected in individual self-efficacy from pre-test (0.73±4.48) to post-test (2.93±4.30; P=0.05; ƞ2=0.18) and pre-test to follow-up (3.20±3.49; P=0.04; ƞ2=0.20) and community led self-efficacy from pre-test (4.40±2.75) to post-test (6.07±3.43; P=0.02; ƞ2=0.24) and pre-test to follow-up (7.07±2.05; P=0.001; ƞ2=0.44). Additionally, significant improvements were found in the LESS-RT following the intervention.

CONCLUSIONS

The intervention based on the HBM led to improvements in individual and community led self-efficacy indicating an enhancement in the participants' confidence in their ability to participate in an ERIPP. Future research should investigate the effectiveness of individualized interventions to improve attitudes towards and adherence to ERIPPs.

Foot impairments contribute to functional limitation in individuals with ankle sprain and chronic ankle instability

PURPOSE

To investigate the clinical measures of foot posture and morphology, multisegmented joint motion and play, strength, and dynamic balance in recreationally active young adults with and without a history of a lateral ankle sprain (LAS), copers, and chronic ankle instability (CAI).

METHODS

Eighty recreationally active individuals (healthy: n = 22, coper: n = 21, LAS: n = 17, CAI: n = 20) were included. Foot posture index (FPI), morphologic measures, joint motion (weight-bearing dorsiflexion (WBDF), rearfoot dorsiflexion, plantar flexion, inversion, eversion; forefoot inversion, eversion; hallux flexion, extension), joint play (proximal and distal tibiofibular; talocrural and subtalar, forefoot; 1st tarsometatarsal and metatarsophalangeal), strength (dorsiflexion, plantar flexion, inversion, eversion, hallux flexion, lesser toe flexion), and Star Excursion Balance Test (SEBT) (anterior, posteromedial, posterolateral) were assessed.

RESULTS

There were no group differences in FPI or morphological measures. LAS and CAI groups had decreased ankle dorsiflexion (p = 0.001) and greater frontal plane motion (p < 0.001), first MT plantar flexion, and sagittal excursion (p < 0.001); increased talocrural glide (p = 0.02) and internal rotation (p < 0.001) and decreased forefoot inversion joint play (p < 0.001); and decreased strength in all measures (p < 0.001) except dorsiflexion compared to healthy controls. The LAS group also demonstrated decreased distal tibiofibular (p = 0.04) and forefoot general laxity (p = 0.05) and SEBT performance (anterior: p = 0.02; posteromedial: p < 0.001; posterolateral: p < 0.001).

CONCLUSION

Individuals with LAS or CAI have increased pain, impaired physiologic and accessory joint motion, ligamentous tenderness, and strength in the foot and ankle. Clinicians should assess the multiple segments of the ankle-foot complex when caring for individuals with an LAS or CAI.

LEVEL OF EVIDENCE

II.

Evaluation of proprioception and postural control at a minimum 1 year follow-up after ankle capsuloligamentous lateralplasty with Brostrom technique: A cohort study

Recovery of postural control and proprioception in patients affected by chronic ankle instability (CAI) and operated on capsulo-ligaments reconstructive surgery lacks of objective assessment. The aim of this study was to evaluate long-term post-surgical postural and proprioceptive control through the DPPS device in a cohort of patients operated on ligaments reconstruction through the modified Brostrom procedure at a minimum follow up of 12 months.Eleven patients with post-traumatic lateral CAI, operated of external capsulo-ligamentous complex repair according to Brostrom technique at a minimum follow-up of 1 year were enrolled. Physical examination and American Orthopaedics Foot and Ankle Society (AOFAS) ankle-hindfoot score. Proprioceptive and postural stability was assessed by DPPS - Delos Postural Proprioceptive System, linked to a computer with a specific software and including a flat table, an electronic unstable proprioceptive board, a Delos Vertical Controller, a monitor and a horizontal bar fitted with an infra-red sensor for hand support.Patients were 5 males and 6 females, mean age of 38.4 ± 12 years. Mean BMI of the patients was 26.8 ± 4.4. Mean follow up was 13.4 ± 2.1. The mean value of (AOFAS) clinical score was 90.3/100. Mean Static Stability Index (SSI) with open eyes was 87.7% (±7.6) in the operated leg and 90.4% (±6.1) in the contra-lateral. SSI with closed eyes was 64.5% (±11.2) in the operated leg and 61.6% (±16.8) in the contra-lateral. Mean Dynamic Stability Index (DSI) without restrictions was 56.2% (±14.6) in the operated leg and 56.8% (±10.6) in the contra-lateral. DSI with restricted upper limbs, had a mean value of 56.3% (±11.4) in the operated leg and 58.1% (±11.9) in the contra-lateral.Re-tensioning capsular-ligamentous surgery of the external compartment for CAI allow to recovery proprioceptive and postural control on the operated side, comparable with data from the contralateral limb and from the healthy population of the same age and sex.

Acute Effect of Kinesiology Taping on Postural Stability in Individuals With Unilateral Chronic Ankle Instability

Background

Chronic ankle instability (CAI), which is characterized by deficient postural control, could be improved through kinesiology taping (KT). However, the effect of KT on postural control in CAI individuals is controversial. Therefore, this study aimed to investigate the acute effect of KT on postural control through computerized dynamic posturography (CDP) and self-perceived sensation in CAI individuals.

Methods

Participants with CAI received four different ankle treatments randomly, including KT, athletic taping (AT), sham taping (ST), and no taping (NT). A series of postural stability measurements was performed using CDP subsequently. The measurements included sensory organization test (SOT), unilateral stance (US), limit of stability (LOS), motor control test (MCT), and adaption test (ADT). In addition, self-perceived sensation was measured through visual analog scaling. Repeated measures analysis of variance was conducted to determine whether the difference among KT, AT, ST, and NT was significant; Bonferroni test was used for post hoc analysis.

Results

No significant difference was observed for parameters in SOT, US, and LOS in four different taping treatments. In MCT, the amplitude scaling scores of KT were 35.87% significantly lower than that of NT [p < 0.001, 95% confidence interval (CI) = 0.548–1.795] in forward-small slip and 21.58% significantly lower than that of ST (p = 0.035, 95% CI = 0.089–3.683) in backward-large slip. In ADT, sway energy scores were 7.59% significantly greater in ST than in AT (p = 0.028, 95% CI = −8.343 to −0.320). For perceived stability, KT was significantly greater than ST (p < 0.001, 95% CI = 0.552–1.899) and NT (p < 0.001, 95% CI = 0.797–2.534), and AT was significantly greater than ST (p = 0.001, 95% CI = 0.423–2.246) and NT (p < 0.001, 95% CI = 0.696–2.852). For perceived comfort, KT was significantly greater than AT (p = 0.001, 95% CI = 0.666–3.196) and NT (p = 0.031, 95% CI = 0.074–2.332), and ST was significantly greater than AT (p = 0.007, 95% CI = 0.349–2.931).

Conclusion

KT and AT have limited effect to facilitate postural control for CAI individuals during SOT, US, and LOS. However, KT and AT could provide effective support to cope with sudden perturbation in MCT and ADT. Moreover, KT provided excellent perceived stability and comfort, whereas AT provided excellent perceived stability but least comfort.

Taping Benefits Ankle Joint Landing Kinematics in Subjects With Chronic Ankle Instability

Context: Although taping has been proven effective in reducing ankle sprain events in individuals with chronic ankle instability, insight into the precise working mechanism remains limited. Objectives: To evaluate whether the use of taping changes ankle joint kinematics during a sagittal and frontal plane landing task in subjects with chronic ankle instability. Design: Repeated measure design. Setting: Laboratory setting. Participants: A total of 28 participants with chronic ankle instability performed a forward and side jump landing task in a nontaped and taped condition. The taping procedure consisted of a double “figure of 6” and a medial heel lock. Main Outcome Measures: 3D ankle joint kinematics was registered. Statistical parametric mapping was used to assess taping effect on mean ankle joint angles and angular velocity over the landing phase. Results: For both the forward and side jump, a less plantar flexed and a less inverted position of the ankle joint were found in the preparatory phase till around touchdown (TD) in the taped condition (P < .05). In addition, for both jump landing protocols, a decreased dorsiflexion angular velocity was found after TD (P < .05). During the side jump protocol, a brief period of increased inversion angular velocity was registered after TD (P < .05). Conclusions: Taping is capable of altering ankle joint kinematics prior to TD, placing the ankle joint in a less vulnerable position at TD.

The Impact of a Previous Ankle Injury on Current Health-Related Quality of Life in College Athletes

CONTEXT

There has been an increased interest in understanding how ankle injuries impact patient outcomes; however, it is unknown how the severity of a previous ankle injury influences health-related quality of life (HRQOL).

OBJECTIVE

To determine the impact of a previous ankle injury on current HRQOL in college athletes.

DESIGN

Cross-sectional study.

SETTING

Athletic training clinics.

PARTICIPANTS

A total of 270 participants were grouped by the severity of a previous ankle injury (severe = 62, mild = 65, and no injury = 143).

MAIN OUTCOME MEASURES

Participants completed the Foot and Ankle Ability Measure (FAAM) and the Short Form 12 (SF-12).

METHODS

A 2-way analysis of variance with 2 factors (injury group and sex) was used to identify interaction and main effects for the FAAM and SF-12.

RESULTS

No interactions were identified between injury group and sex. Significant main effects were observed for injury group, where the severe injury group scored lower than athletes with mild and no injuries on the FAAM activities of daily living, FAAM Global, and SF-12 mental health subscale scores. In addition, a main effect was present for sex in the SF-12 general health, social functioning, and mental health subscales in which females reported significantly lower scores than males.

CONCLUSIONS

Our findings suggest that a severe ankle injury impacts HRQOL, even after returning back to full participation. In addition, females tended to report lower scores than males for aspects of the SF-12, suggesting that sex should be considered when evaluating HRQOL postinjury. As a result, clinicians should consider asking athletes about their previous injury history, including how much time was lost due to the injury, and should mindful of returning athletes to play before they are physiologically and psychologically ready, as there could be long-term negative effects on the patients' region-specific function as well as aspects of their HRQOL.

Effective Treatment for Chronic Ankle Instability During Lateral Step-Down-Kinesiology Tape, Resistance Exercise, or Both Accompanied With Heel Raise-Lower Exercise?

CONTEXT

Kinesiology tape (KT), multidirectional resistance exercise, and interventions for decreased ankle dorsiflexion range of motion are gaining popularity in the treatment of patients with chronic ankle instability (CAI). However, there is limited evidence of the effectiveness of combined interventions in patients with CAI.

OBJECTIVES

To compare the effects of KT alone, KT with resistance exercise (KT + resistance), and KT with resistance and heel raise-lower exercise (KT + resistance + heel) on the results of the dynamic balance test (star excursion balance test [SEBT]), functional performance (lateral step-down test), and ankle muscle activation in patients with CAI.

DESIGN AND SETTING

This study used a repeated-measures design in a laboratory setting.

MAIN OUTCOME MEASURES

The participants completed 3 different interventions with a 24-hour rest period between interventions. The SEBT, lateral step-down test, and ankle muscle activation results were used as the outcome measures. All outcomes were assessed before and immediately after the 3 interventions.

RESULTS

The results of the SEBT-anteromedial direction significantly increased with KT + resistance (78.61 [16.11] cm, P = .01, ES = 0.50) and KT + resistance + heel (76.94 [16.00] cm, P = .03, ES = 0.33) in comparison with the baseline values (73.68 [12.84] cm). Additionally, the result of the SEBT-anteromedial direction was significantly greater with KT + resistance (78.61 [16.11] cm) than with KT alone (76.00 [14.90] cm, P = .05, ES = 0.18). The number of errors during the lateral step-down test was significantly lower for the KT alone (2.16 [0.90] errors, P = .02, ES = 0.46), KT + resistance (2.10 [0.79] errors, P = .01, ES = 0.54), and KT + resistance + heel (2.03 [0.75] errors, P = .003, ES = 0.61) interventions than the baseline values (2.55 [0.85] errors).

CONCLUSIONS

Patients with CAI should be encouraged to perform KT + resistance to improve balance.

Relationship Between Isokinetic Muscle Strength and Functional Tests in Chronic Ankle Instability

Isokinetic muscle strength measurements and functional tests are usually performed to evaluate ankle condition in chronic ankle instability (CAI), yet there is no clear demonstration of the relationship between isokinetic muscle strength and functional tests. The objective of this study was to evaluate the relationship between isokinetic muscle strength and functional tests in CAI. Between April 2014 and August 2016, 103 patients with unilateral CAI were studied. Single-leg balance, single-heel raise, and single-leg squat tests were performed for static balancing assessment. Single-leg hop, double-leg jump, and sidestep tests were performed for dynamic balancing assessment. The isokinetic muscle strength of both ankles was measured using a dynamometer. The involved ankle showed lower muscle strength in inversion than the uninvolved ankle, while eversion, dorsiflexion, and plantarflexion muscle strength had no significant differences between ankles. There were significant correlations between the isokinetic muscle strength of inversion and the single-leg balance test, single-heel raise test, and sidestep test (Pearson's r; 0.246, 0.514, and 0.229 at 30°/second; 0.288, 0.473, and 0.239 at 180°/second, respectively). The single leg balance, single heel raise, and sidestep tests are useful to assess not only ankle functional performance but also isokinetic muscle strength. Among these tests, the single heel raise test was the most reliable test to reflect muscle strength deficiency in CAI.