Clinical and laboratory measures associated with health-related quality of life in individuals with chronic ankle instability

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.

Association of Diaphragm Contractility and Postural Control in a Chronic Ankle Instability Population: A Preliminary Study

BACKGROUND

Altered reorganization of the sensorimotor system after an initial lateral ankle sprain may lead to a chronic neuromuscular maladaptation in multiple body locations. Specifically, decreased diaphragm contractility has been observed in patients with chronic ankle instability (CAI). The diaphragm has an essential role in postural control. Decreased diaphragm contractility could associate with diminished postural control commonly observed in patients with CAI. However, no study has determined if diaphragm contractility contributes to postural control in a CAI population.

HYPOTHESIS

Decreased diaphragm contractility would be negatively associated with static postural control in patients with CAI.

STUDY DESIGN

Cross-sectional study design.

LEVEL OF EVIDENCE

Level 4.

METHODS

A total of 15 participants with CAI participated voluntarily. An ultrasonography assessment was performed to quantify the right and left hemidiaphragm thickness at the end of resting inspiration and expiration in supine while breathing quietly. The degree of diaphragm contractility was calculated from the diaphragm thickness. Participants performed 3 eyes-open trials of a 20-second single-leg balance task on the involved limb. Static postural control measures included the center of pressure velocity (COPV) and mean of time-to-boundary (TTB) minima in the anteroposterior (AP) and mediolateral directions.

RESULTS

Moderate correlations of the right hemidiaphragm contractility were observed with COPV (ρ = -0.54) and TTB mean minima (ρ = 0.56) (P < 0.05) in the AP direction. The left hemidiaphragm contractility was moderately correlated with COPV (ρ = -0.56) and TTB mean minima (ρ = 0.60) (P < 0.05) in the AP direction.

CONCLUSION

Lower diaphragm contractility may be associated with diminished static postural control in the AP direction in patients with CAI.

CLINICAL RELEVANCE

This study highlights diaphragm contractility could be a potential connection with diminished static postural control in patients with CAI. Our data raise new avenues for future exploration including potential beneficial effects of implementation of diaphragm breathing exercises and techniques for restoring static postural control in patients with CAI.

Cortical Activation During Single-Legged Stance in Patients With Chronic Ankle Instability

CONTEXT

Chronic ankle instability (CAI) has been considered a neurophysiological condition, with dysfunctional somatosensory and motor system excitability. However, few researchers have explored the changes in cortical activation during balance tasks of patients with CAI.

OBJECTIVE

To compare the cortical activity during single-legged stance among CAI, copers, and uninjured control participants and to compare dynamic balance across groups.

DESIGN

Cross-sectional study.

SETTING

Biomechanics laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 22 participants with CAI (median [interquartile range]; age = 34.5 [11.0] years, height = 170.0 [15.8] cm, mass = 67.0 [16.2] kg), 17 copers (age = 27.0 [14.0] years, height = 170.0 [9.5] cm, mass = 66.5 [16.5] kg), and 21 uninjured control participants (age = 25.0 [10.5] years, height = 170.0 [11.0] cm, mass = 64.0 [16.5] kg).

MAIN OUTCOME MEASURE(S)

Participants performed single-legged stance while cortical activation was tested with functional near-infrared spectroscopy. The peak oxyhemoglobin response of the activated cortex was calculated and compared across groups. The Y-Balance test outcomes and patient-reported outcomes were assessed and compared across groups.

RESULTS

The CAI group had worse Y-balance test and patient-reported outcomes than the coper and uninjured control groups. Differences in the peak oxyhemoglobin response were observed for the primary somatosensory cortex (S1; F2,57 = 4.347, P = .017, ηp2 = 0.132) and superior temporal gyrus (STG; F2,57 = 4.548, P = .015, ηp2 = 0.138). Specifically, copers demonstrated greater activation in S1 and STG than the CAI (d = 0.73, P = .034, and d = 0.69, P = .043, respectively) and uninjured control (d = 0.77, P = .036, and d = 0.88, P = .022, respectively) groups. No differences were found in the cortical activation between CAI and uninjured control participants.

CONCLUSIONS

Copers displayed greater cortical activation in S1 and STG than CAI and uninjured control participants. Greater activation in S1 and STG suggested a better ability to perceive somatosensory stimuli and may represent a compensatory mechanism that allows copers to maintain good functional ability after the initial severe ankle sprain.

Yoga as a balance intervention for middle-age and older adults with history of lateral ankle sprain: An exploratory study

INTRODUCTION

Balance deficiencies are common among aging adults. Musculoskeletal injuries such as lateral ankle sprains (LAS) also contribute to compromised balance; potentially amplifying the postural insufficiencies in these age groups with a history of LAS. Yoga has emerged as an effective balance training intervention for aging adults; but limited application exists in these age cohorts with LAS history. This study may provide important guidance for the implementation of this intervention in these populations.

METHODS

In this cohort design study, middle-age and older adults with a history of LAS completed an 8-week beginner-level yoga class. Balance was measured before and after the yoga intervention statically (force plate) and dynamically (star excursion balance test [SEBT]) using single-limb balance tasks.

RESULTS

Following the yoga intervention, older adults improved static postural control in the anterior-posterior direction, as well as dynamic postural control in selected reach directions of the SEBT relative to the middle-age adults.

CONCLUSION

This is an important step in exploring how to help the aging population that likely has amplifications in balance deficiencies due to a common musculoskeletal injury, LAS. While more work is needed to determine how to optimize and document balance improvements in aging adults with LAS history, yoga appears to be a promising form of intervention, particularly for older adults.

Exploratory factor analysis of the fear-avoidance beliefs questionnaire in patients with chronic ankle instability

PURPOSE

To perform an exploratory factor analysis of the Fear-Avoidance Beliefs Questionnaire in patients with chronic ankle instability.

METHODS

A cross-sectional survey study was utilized. The Fear-Avoidance Beliefs Questionnaire was administered to patients with chronic ankle instability who met the inclusion criteria. Both an unrestricted and restricted factor analysis with varimax rotation were utilized to explore the factor structure of the instrument. Kaiser-Meyer-Olkin values were used to determine sampling adequacy. Bartlett's test of sphericity was used to justify that the correlations were suitable for the principal component analysis.

RESULTS

The restricted two-factor analysis resulted in two factors with acceptable internal consistency values. The Keiser-Meyer-Olkin value was acceptable (0.81), and Bartlett's test of sphericity was significant (χ² (55) = 515.59, p < 0.001).

CONCLUSION

The ankle-specific Fear-Avoidance Beliefs Questionnaire consists of two stable factors and should be used to further examine fear-avoidance beliefs in people with chronic ankle instability.

The Immediate Carryover Effects of Peroneal Functional Electrical Stimulation Differ between People with and without Chronic Ankle Instability

Chronic ankle instability (CAI) is a common condition that may develop after an ankle sprain. Compared with healthy individuals, those with CAI demonstrate excessive ankle inversion and increased peroneal electromyography (EMG) activity throughout the stance phase of gait, which may put them at greater risk for re-injury. Functional electrical stimulation (FES) of targeted muscles may provide benefits as a treatment modality to stimulate immediate adaptation of the neuromuscular system. The present study investigated the effect of a single, 10 min peroneal FES session on ankle kinematics and peroneal EMG activity in individuals with (n = 24) or without (n = 24) CAI. There were no significant differences in ankle kinematics between the groups before the intervention. However, after the intervention, healthy controls demonstrated significantly less ankle inversion between 0-9% (p = 0.009) and 82-87% (p = 0.011) of the stance phase. Furthermore, a significant within-group difference was observed only in the control group, demonstrating increased ankle eversion between 0-7% (p = 0.011) and 67-81% (p = 0.006) of the stance phase after the intervention. Peroneal EMG activity did not differ between groups or measurements. These findings, which demonstrate that peroneal FES can induce ankle kinematics adaptations during gait, can help to develop future interventions for people with CAI.

Validation of Foot and Ankle Ability Measure (FAAM) and the Foot and Ankle Outcome Score (FAOS) in individuals with chronic ankle instability: a cross-sectional observational study

Background

Ankle sprain is the most common lower limb injury in physically active individuals. Loss of function, decreased postural control (PC), strength deficit, and reduced range of motion (ROM) are common after acute lateral ankle sprains. Some patients experienced long lasting symptoms, with recurrent sprains, and episodes of giving-way: a condition known as chronic ankle instability (CAI). Evaluating the function in patients with CAI in the clinical environment is important to identify the severity of the condition, in addition to allowing to assess the effectiveness of a given treatment. The aim of this study was to investigate the validation of the Foot and Ankle Ability Measure (FAAM) and the Foot and Ankle Outcome Score (FAOS) in terms of muscle strength, PC and ROM in adults with CAI.

Methods

This is a cross-sectional study. Individuals with CAI aged between 18 and 45 years were eligible. Individuals with CAI were identified using the Identification of Functional Ankle Instability (IdFAI). All patients filled in the FAAM and FAOS scores. Muscle strength was assessed by manual dynamometry, ROM by the Lunge test, PC by computerized posturography, modified Star Excursion Balance Test (mSEBT) and modified Balance Error Score System (mBESS).

Results

50 participants were enrolled in the present study. The mean age of the patients was 27.2 ± 6.3 years, and the mean body mass index was 26.4 ± 4.8 kg/m2. 58% (29 of 50) were men and 42% (21 of 50) women. 18 individuals had unilateral (36%) and 32 bilateral (64%) CAI. The results of FAAM were associated with MCT, mSEBT, invertor muscles strength, plantar flexor muscles strength, dorsiflexor muscles strength, and external hip rotator muscles strength (P < 0.05). The results of FAOS were associated with mSEBT, invertor muscles strength, plantar flexor muscles strength, dorsiflexor muscles strength, evertor muscles strength, and external hip rotator muscles strength, and mBEES (P < 0.05).

Conclusion

Both the FAAM and FAOS demonstrated validity to evaluate postural control and muscle strength in patients with CAI, while no association was found in relation to ankle dorsiflexion.

Health-Related Quality of Life Among Patients With Painful Chronic Ankle Instability

More than half of individuals with chronic ankle instability (CAI) experience lingering pain from a previous injury. However, there is little empirical evidence investigating the role pain has on health-related quality of life (HRQL). The purpose of this cross-sectional study was to compare physical and psychological HRQL between CAI individuals with and without pain. Group comparisons demonstrated that CAI individuals with pain displayed a lower physical and mental HRQL than those without pain. In addition, CAI individuals with pain reported greater injury-related fear. These findings suggest that persistent pain compounds the negative effect that ankle joint instability has on physical and mental HRQL outcomes. Therefore, conservative therapies should consider multimodal approaches rather than focusing on joint stability alone.

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.

Lack of Definition of Chronic Ankle Instability With Arthrometer-Assisted Ankle Joint Stress Testing: A Systematic Review of In Vivo Studies

Despite extensive research on ankle instability a consensual and clear objective definition for pathological mechanical lateral ankle instability is yet to be determined. This systematic review aimed to summarize current available arthrometric devices, measuring methods and lateral ankle laxity outcomes in patients with chronic ankle instability that underwent objective arthrometric stress measurement. Sixty-eight studies comprising a total of 3,235 ankles with chronic ankle instability were included. Studies reported a wide range of arthrometric devices, testing position and procedures, and measuring methods. For the anterior drawer test, the average mean differences between injured and uninjured ankles ranged from -0.9 to 4.1 mm, and total translation in the injured ankle from 3.2 to 21.0 mm. Most common pathological threshold was ≥4 mm or ≥10 mm unilaterally and ≥3 mm bilaterally. For the talar tilt test, the average mean differences between injured and uninjured ankles ranged from 0.0° to 8.0°, and total tilt from injured ankle from 3.3 to 60.2°. Most common pathological threshold was ≥ 10° unilaterally and ≥ 6° mm bilaterally. It was found high heterogeneity in the scientific literature regarding the arthrometric devices, use of concomitant imaging and measuring methods of arthrometer-assisted anterior drawer and talar tilt tests which led to variable laxity outcomes in individuals with chronic ankle instability. Future studies should focus on standardizing the testing and measuring methods for an objective definition of mechanical ankle instability.

Isometric Hip Strength and Patient-Reported Outcomes of Individuals With and Without Chronic Ankle Instability

CONTEXT

Strength deficits and decreased scores on generic, dimension-specific, and region-specific health-related quality of life (HRQL) PRO measures are commonly documented among individuals with chronic ankle instability (CAI). However, it is unknown if there is a relationship between hip strength and self-reported patient-reported outcome (PRO) scores.

OBJECTIVE

To compare isometric peak torque for hip-extension (H-EXT) and hip-abduction (H-ABD), as well as PRO scores between CAI, lateral ankle sprain copers (LAS copers), and uninjured controls (UC). The secondary purpose was to examine the relationship between isometric hip peak torque and PROs in participants with CAI.

DESIGN

Cross-sectional.

SETTING

Laboratory.

PARTICIPANTS

Sixty-three individuals, 45 women (23.02 [3.83] y, 165.91 [7.55] cm, 67.28 [11.95] kg) and 18 men (26.28 [5.43] y, 179.28 [9.01] cm, 83.87 [13.26] kg), grouped as uninjured control (n = 26), LAS coper (n = 15), or CAI (n = 22).

MAIN OUTCOME MEASURES

The Foot and Ankle Ability Measure was used to assess region-specific HRQL. The Fear Avoidance Beliefs Questionnaire was used to assess injury-related fear. The Disablement in Physically Active was used to assess global HRQL. Isometric peak torque was measured with a handheld dynamometer for H-EXT and H-ABD.

RESULTS

No group differences were observed for H-ABD (P = .34) or H-EXT (P = .35). The CAI group had significantly worse scores on all PROs compared with LAS coper (P < .001) and HC (P < .001). Moderate-weak correlations were found between H-ABD and Foot and Ankle Ability Measure-activities of daily living (P = .047; ρ = .392) and Foot and Ankle Ability Measure-Sport (P = .013; ρ = .482) and H- EXT and Fear Avoidance Beliefs Questionnaire-Work (P = .007; ρ = -.517).

CONCLUSIONS

Individuals with CAI displayed lower HRQL based on worse scores on generic, dimension-specific, and region-specific PROs compared with LAS copers and uninjured controls. There were no significant between-group differences for H-EXT and H-ABD isometric peak torque production, but there was a moderate positive relationship between isometric H-ABD and self-reported ankle disability in individuals with CAI.

Impact of kinesiophobia on physical function and quality of life in functional ankle instability individuals: an observational study

Background

Functional ankle instability is a common musculoskeletal condition affecting the community. It is characterized by repetitive bouts of giving away, recurrent sprains, and sensation of instability leading to functional deficits in an individual. The present study aimed to assess the influence of kinesiophobia on physical function and quality of life in participants with functional ankle instability. A cross-sectional study was conducted in 30 participants with functional ankle instability. Kinesiophobia was assessed using the 17-item Tampa Scale of Kinesiophobia, physical function using the Foot and Ankle Ability Measure (FAAM) and the FAAM-Sport version (FAAM-S), and quality of life using SF-36.

Results

The TSK score showed a moderate negative correlation with FAAM-S (r = −0.5, p = 0.005) and a weak negative correlation with SF-36 physical component summary (r = −0.42, p = 0.02). However, TSK showed no significant correlation with FAAM-ADL and SF-36 mental component summary.

Conclusion

Increased fear of movement, reduced physical function, and health-related quality of life were observed in functional ankle instability individuals. Hence, evaluation of these parameters is imperative in these individuals.

Ankle Stability and Movement Coordination Impairments: Lateral Ankle Ligament Sprains Revision 2021

This revised clinical practice guideline (CPG) addresses the distinct but related lower extremity impairments of those with a first-time lateral ankle sprain (LAS) and those with chronic ankle instability (CAI). Depending on many factors, impairments may continue following injury. While most individuals experience resolution of symptoms, complaints of instability may continue and are defined as CAI. The aims of the revision were to provide a concise summary of the contemporary evidence since publication of the original guideline and to develop new recommendations or revise previously published recommendations to support evidence-based practice. J Orthop Sports Phys Ther 2021;51(4):CPG1-CPG80. doi:10.2519/jospt.2021.0302.

The Effect of Attending Physical Rehabilitation After the First Acute Lateral Ankle Sprain on Static Postural Control in Patients With Chronic Ankle Instability

CONTEXT

Static postural control deficits are commonly documented among individuals with chronic ankle instability (CAI). Evidence suggests individuals with CAI who seek medical attention after an ankle sprain report fewer subjective symptoms. It is unknown if seeking medical attention and receiving supervised physical rehabilitation has a similar effect on objective outcomes, such as static postural control.

OBJECTIVE

To compare measures of single-limb postural control and center of pressure (COP) location between participants with CAI who did or did not self-report attending supervised rehabilitation at the time of their first lateral ankle sprain.

DESIGN

Retrospective cohort.

SETTING

Laboratory. Patients (or Other Participants): Twenty-nine participants with CAI who did (n = 14) or did not (n = 15) self-report attending supervised rehabilitation.

INTERVENTION(S)

Self-reported attendance or not of supervised rehabilitation at the time of initial injury.

MAIN OUTCOME MEASURES

Participants performed three 20-second trials of single-limb stance on a force plate with eyes open. Main outcome measures included the COP velocities, time-to-boundary (TTB) absolute minima, mean of TTB minima, and SD of TTB minima in the anteroposterior and mediolateral directions. The spatial distribution of the COP data points under the foot was quantified within 4 equally proportional sections labeled anteromedial, anterolateral, posteromedial, and posterolateral.

RESULTS

Participants who reported attending supervised rehabilitation after their initial ankle sprain had a lower COP velocity in the anterior-posterior direction (P = .030), and higher TTB anterior-posterior absolute minimum (P = .033) and mean minima (P = .050) compared with those who did not attend supervised rehabilitation.

CONCLUSIONS

Among individuals with CAI, not attending supervised rehabilitation at the time of initial injury may lead to worse static postural control outcomes. Clinicians should continue advocating for patients recovering from an acute ankle sprain to seek medical attention and provide continued care in the form of physical rehabilitation.

Health-Related Quality of Life Among Middle-Aged Adults With Chronic Ankle Instability, Copers, and Uninjured Controls

CONTEXT

People with chronic ankle instability (CAI) display a lower regional and global health-related quality of life (HRQoL). Examinations of HRQoL outcomes associated with CAI have addressed younger adults, restricting our understanding of the long-term consequences of CAI.

OBJECTIVE

To compare ankle regional and global HRQoL in middle-aged participants with and those without CAI.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 59 middle-aged volunteers, consisting of 18 with CAI (age = 50.2 ± 9.3 years), 17 who were ankle-sprain copers (age = 54.5 ± 8.7 years), and 24 uninjured controls (age = 56.7 ± 10.0 years).

MAIN OUTCOME MEASURE(S)

Participants completed the Foot and Ankle Disability Index (FADI) and the Patient-Reported Outcomes Measurement Information System Adult Profile. Regional HRQoL was assessed using the FADI Activities of Daily Living and Sport subscales. Global HRQoL was measured using the 43-item Patient-Reported Outcomes Measurement Information System Adult Profile, which contains 7 short forms-Physical Function, Pain Interference, Fatigue, Depression, Sleep Disturbance, Anxiety, and Ability to Participate in Social Roles and Activities. Separate Kruskal-Wallis tests were used to determine between-groups differences.

RESULTS

Middle-aged participants with CAI had lower scores on both subscales of the FADI than the coper and control groups (all P values <.001). Participants with CAI scored lower on the Physical Function (U = 116.0, z = -2.78, P = .005) and Ability to Participate in Social Roles and Activities (U = 96.0, z = -3.09, P = .002) subscales but higher on the Pain Interference (U = 144.0, z = -2.36, P = .02), Fatigue (U = 110.0, z = -2.72, P = .006), and Depression (U = 110.5, z = -2.91, P = .004) subscales than the control group. Participants with CAI also scored lower on the Physical Function (U = 74.5, z = -2.79, P = .005) and Ability to Participate in Social Roles and Activities (U = 55.0, z = -3.29, P = .001) subscales but higher on the Fatigue (U = 90.0, z = -2.09, P = .04) and Depression (U = 96.5, z = -1.97, P = .048) subscales than the coper group.

CONCLUSIONS

Middle-aged participants with CAI displayed worse ankle regional and global HRQoL than their age-matched healthy counterparts and copers. These results demonstrated that CAI can affect HRQoL outcomes in middle-aged adults.

Symmetry does not Indicate Recovery: Single-leg Hop Before and After a Lower Extremity Injury

Current recommendations for return-to-play decision-making involve comparison of the injured limb to the uninjured limb. However, the use of the uninjured limb as a comparison for hop testing lacks empirical evidence. Thus, the purpose of this study was to determine the effects of lower extremity injury on limb symmetry and performance on the single-leg hop for distance. Two-hundred thirty-six adolescent athletes completed the single-leg hop for distance before the beginning of the season (pre-injury). Forty-four adolescent athletes sustained a lower extremity injury (22 ankle and 12 knee) and missed at least three days of sports participation. All individuals had completed the single-leg hop for distance before the beginning of the season (pre-injury) and at discharge (post-injury). Injured limb single-leg hop for distance significantly decreased at return-to-play from pre-injury with a mean decrease of 48.9 centimeters; the uninjured limb also significantly decreased, with a mean decrease of 33.8 centimeters. Limb symmetry did not significantly change pre- to post-injury with a mean difference of 1.5%. Following a lower extremity injury, single-leg hop for distance performance degrades not only for the injured limb but also the uninjured limb. However, limb symmetry did not change following a lower extremity injury.

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.

Altered movement strategy of chronic ankle instability individuals with postural instability classified based on Nyquist and Bode analyses

BACKGROUND

The aim of the current study was to assess movement strategies during a single leg balance in chronic ankle instability individuals with unstable postural control strategy identified by Nyquist and Bode analyses in conjunction with sample entropy.

METHODS

Thirty-three participants with self-reported chronic ankle instability and 22 healthy controls performed single-leg eyes closed static balance trials. The sagittal and frontal plane kinematics in the lower extremity and trunk as well as center of pressure trajectories were recorded during three, 20-second trials. The Nyquist and Bode stability analyses, which classify center of pressure waveforms as stable based on the resulting gain and phase margins, were performed to identify the presence of postural control deficits. Sample entropy was implemented to analyze movement strategies during the task.

FINDINGS

Based on the Nyquist and Bode stability analyses, we included 19 out of 33 chronic ankle instability participants with unstable postural control strategy and 16 out of 22 controls with stable postural control strategy in the final analyses. Chronic ankle instability participants demonstrated a significantly lower sample entropy value in sagittal and frontal plane trunk kinematics and sagittal plane hip kinematics compared to the controls. No between-group differences existed in other kinematic measures.

INTERPRETATION

The lower sample entropy values in participants with chronic ankle instability indicates that those with postural control deficits may increase reliance on the trunk and hip joint contributions to the maintenance of postural control, reflecting changes in the sensorimotor constraints on movement patterns during the task.

The Relationship Among 3 Generic Patient-Reported Outcome Instruments in Patients With Lower Extremity Health Conditions

CONTEXT

Generic patient-reported outcome (PRO) instruments are designed to capture health-related quality-of-life outcomes and to determine treatment effectiveness from the patient's perspective. Multiple generic PROs are used in clinical practice, and an investigation of the psychometric properties of these instruments in a high-functioning, physically active population is important for the future use of these instruments.

OBJECTIVE

To determine the relationship among 3 generic PROs: the modified Disablement in the Physically Active (mDPA) Scale, the Patient-Reported Outcome Measurement Information System Physical Function (PROMIS-PF), and the Short Form 12 (SF-12) in physically active patients seeking treatment for a lower extremity health condition.

DESIGN

Cross-sectional study.

SETTING

Athletic training clinical facility, physical therapy clinic.

PATIENTS OR OTHER PARTICIPANTS

One hundred patients seeking rehabilitation services for a lower extremity health condition.

MAIN OUTCOME MEASURE(S)

All patients completed a demographic questionnaire and the 3 generic PROs at 1 time point during their rehabilitation: the mDPA-Total, mDPA-physical summary component (mDPA-PSC), mDPA-mental summary component (mDPA-MSC), the PROMIS-PF, and SF-12 mental component summary (SF-MCS) and physical component summary (SF-PCS). Separate Spearman rank (r) correlations were performed to assess the strength of the relationship among PRO instruments. The floor and ceiling effects were also examined.

RESULTS

A strong relationship was present between the SF-12 PCS and the mDPA-Total (r = -0.65), the mDPA-PSC (r = -0.64), and the PROMIS-PF (r = 0.65). Significant moderate relationships were identified between the mDPA-MSC and the SF-12 PCS (r = -0.43) and MCS (r = -0.53). Weak relationships were noted between the mDPA-Total and SF-12 MCS (r = -0.21) and the SF-12 MCS and mDPA-PSC (r = -0.10) and PROMIS-PF (r = 0.20).

CONCLUSIONS

The PROMIS-PF and mDPA had good convergent and divergent validity. Clinicians treating physically active patients should consider these instruments for use in clinical practice. Future researchers should examine additional psychometric properties of these instruments in physically active patients.

Nonlinear Dynamic Measures for Evaluating Postural Control in Individuals With and Without Chronic Ankle Instability

This study aimed to compare time-to-boundary and sample entropy during a single-leg balance task between individuals with chronic ankle instability (CAI), lateral ankle sprain copers, and healthy controls. Twenty-two participants with CAI, 20 lateral ankle sprain copers, and 24 healthy controls performed a single-leg balance task during an eyes-closed condition. Participants with CAI exhibited lower time-to-boundary values compared with lateral ankle sprain copers and healthy controls. However, we did not find differences in sample entropy variables between cohorts. A decrease in time-to-boundary values in participants with CAI indicated that CAI may constrain the ability of the sensorimotor system to maintain the center of pressure within the boundaries of the base of support. However, the regularity of the center of pressure velocity time series appears not to be altered in the CAI cohort in this study.

College Athletes With Ankle Sprain History Exhibit Greater Fear-Avoidance Beliefs

Context: Postinjury, college athletes have reported elevated levels of fear. However, it is unclear how a history of ankle sprain impacts injury-related fear. Objective: The aim of this study was to determine if Fear-Avoidance Beliefs Questionnaire (FABQ) scores differ between college athletes with a history of a single ankle sprain, those with recurrent ankle sprains, and healthy controls. Design: Cross-sectional design. Setting: National Collegiate Athletic Association institutions. Patients: From a large database of college athletes, 75 participants with a history of a single ankle sprain, 44 with a history of recurrent ankle sprains (≥2), and 28 controls with no injury history were included. Main Outcome Measures: Participants completed an injury history questionnaire and the FABQ. On the injury history form, the participants were asked to indicate if they had ever sustained an ankle sprain and, if yes, to describe how many. FABQ scores ranged from 0 to 66 with higher scores representing greater fear. Results: Athletes with a history of recurrent ankle sprains (median, 28.00; interquartile range, 18.25–38.00) reported higher levels of fear than those with a history of a single ankle sprain (21.00; 8.00–31.00; P = .03; effect size = 0.199) and healthy controls (5.50; 0.00–25.00; P < .001; effect size = 0.431). Athletes with a history of a single sprain reported greater fear than healthy controls (P = .01, effect size = 0.267). Athletes with a history of a single sprain reported greater fear than healthy controls (P = .02, effect size = 0.23). Conclusions: College athletes with a history of ankle sprain exhibited greater levels of fear on the FABQ than healthy controls. These findings suggest that ankle sprains in general may increase injury-related fear and that those with a history of recurrent sprains are more vulnerable.

Balance- and Strength-Training Protocols to Improve Chronic Ankle Instability Deficits, Part I: Assessing Clinical Outcome Measures

CONTEXT

  Functional rehabilitation may improve the deficits associated with chronic ankle instability (CAI).

OBJECTIVE

  To determine if balance- and strength-training protocols improve the balance, strength, and functional performance deficits associated with CAI.

DESIGN

  Randomized controlled clinical trial.

SETTING

  Athletic training research laboratory.

PATIENTS OR OTHER PARTICIPANTS

  Participants were 39 volunteers with CAI, which was determined using the Identification of Functional Ankle Instability Questionnaire. They were randomly assigned to 1 of 3 groups: balance-training protocol (7 males, 6 females; age = 23.5 ± 6.5 years, height = 175.0 ± 8.5 cm, mass = 72.8 ± 10.9 kg), strength-training protocol (8 males, 5 females; age = 24.6 ± 7.7 years, height = 173.2 ± 9.0 cm, mass = 76.0 ± 16.2 kg), or control (6 males, 7 females; age = 24.8 ± 9.0 years, height = 175.5 ± 8.4 cm, mass = 79.1 ± 16.8 kg).

INTERVENTION(S)

  Each group participated in a 20-minute session, 3 times per week, for 6 weeks. The control group completed a mild to moderately strenuous bicycle workout.

MAIN OUTCOME MEASURE(S)

  Participants completed baseline testing of eccentric and concentric isokinetic strength in each ankle direction (inversion, eversion, plantar flexion, and dorsiflexion) and the Balance Error Scoring System (BESS), Star Excursion Balance Test (SEBT), and side-hop functional performance test. The same variables were tested again at 6 weeks after the intervention. Two multivariate repeated-measures analyses of variance with follow-up univariate analyses were conducted. The α level was set a priori at .05.

RESULTS

  We observed time-by-group interactions in concentric ( P = .02) and eccentric ( P = .01) inversion, eccentric eversion ( P = .01), concentric ( P = .001) and eccentric ( P = .03) plantar flexion, BESS ( P = .01), SEBT ( P = .02), and side hop ( P = .004). With pairwise comparisons, we found improvements in the balance- and strength-training protocol groups in concentric and eccentric inversion and concentric and eccentric plantar flexion and the BESS, SEBT, and side hop (all P values = .001). Only the strength-training protocol group improved in eccentric eversion. The control group did not improve in any dependent variable.

CONCLUSIONS

  Both training protocols improved strength, balance, and functional performance. More clinicians should incorporate hop-to-stabilization exercises into their rehabilitation protocols to improve the deficits associated with CAI.

Health-related quality of life is decreased in middle-aged adults with chronic ankle instability

OBJECTIVES

The purpose of this study was to determine whether health-related quality of life and region-specific outcomes differ between middle-aged adults with and without chronic ankle instability.

DESIGN

Cross-sectional.

METHODS

Two hundred middle-aged individuals (40 years or older) volunteered to participate in the study. There were 75 individuals classified as having chronic ankle instability (51.5±7.3years, 175.8±3.7cm, 86.5±18.9kg) and 125 classified as not having chronic ankle instability (53.2±7.3years, 176.2±5.4cm, 81.3±17.6kg). Participants completed the Identification of Functional Ankle Instability as the inclusionary survey and the Internal Ankle Consortium guidelines were followed to classify individuals. Following the inclusionary survey participants completed the American Academy of Orthopaedic Surgeons Lower Limb Questionnaire and the Short Form-36 v2.

RESULTS

The Academy of Orthopaedic Surgeons Lower Limb Questionnaire, and the Physical Component Summary score of the Short Form-36 v2 were statistically different between groups (p<0.05). Specifically, the mean difference was 16.7 points and 12.3 points for the Academy of Orthopaedic Surgeons Lower Limb Questionnaire and the Physical Component Summary score, respectively, with the CAI participants scoring worse.

CONCLUSIONS

Individuals with CAI displayed decreased generic health-related quality of life and reduced region-specific ankle function.

Predictors of chronic ankle instability: Analysis of peroneal reaction time, dynamic balance and isokinetic strength

BACKGROUND

Previous studies have reported the factors contributing to chronic ankle instability, which could lead to more effective treatments. However, factors such as the reflex response and ankle muscle strength have not been taken into account in previous investigations.

METHODS

Fifty recreational athletes with chronic ankle instability and 55 healthy controls were recruited. Peroneal reaction time in response to sudden inversion, isokinetic evertor muscle strength and dynamic balance with the Star Excursion Balance Test and the Biodex Stability System were measured. The relationship between the Cumberland Ankle Instability Tool score and performance on each test was assessed and a backward multiple linear regression analysis was conducted.

FINDINGS

Participants with chronic ankle instability showed prolonged peroneal reaction time, poor performance in the Biodex Stability System and decreased reach distance in the Star Excursion Balance Test. No significant differences were found in eversion and inversion peak torque. Moderate correlations were found between the Cumberland Ankle Instability Tool score and the peroneal reaction time and performance on the Star Excursion Balance Test. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test accounted for 36% of the variance in the Cumberland Ankle Instability Tool.

INTERPRETATION

Dynamic balance deficits and delayed peroneal reaction time are present in participants with chronic ankle instability. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test were the main contributing factors to the Cumberland Ankle Instability Tool score. No clear strength impairments were reported in unstable ankles.

Assessment of Relationships Between Joint Motion Quality and Postural Control in Patients With Chronic Ankle Joint Instability

Study Design Controlled laboratory study, cross-sectional. Background Lateral ankle sprains are among the most common injuries encountered during athletic participation. Following the initial injury, there is an alarmingly high risk of reinjury and development of chronic ankle instability (CAI), which is dependent on a combination of factors, including sensorimotor deficits and changes in the biomechanical environment of the ankle joint. Objective To evaluate CAI-related disturbances in arthrokinematic motion quality and postural control and the relationships between them. Methods Sixty-three male subjects (31 with CAI and 32 healthy controls) were enrolled in the study. For arthrokinematic motion quality analysis, the vibroarthrographic signals were collected during ankle flexion/extension motion using an acceleration sensor and described by variability (variance of mean squares [VMS]), amplitude (mean of 4 maximal and 4 minimal values [R4]), and frequency (vibroarthrographic signal bands of 50 to 250 Hz [P1] and 250 to 450 Hz [P2]) parameters. Using the Biodex Balance System, single-leg dynamic balance was measured by overall, anteroposterior, and mediolateral stability indices. Results Values of vibroarthrographic parameters (VMS, R4, P1 and P2) were significantly higher in the CAI group than those in the control group (P<.01). Similar results were obtained for all postural control parameters (overall, anteroposterior, and mediolateral stability indices; P<.05). Moreover, correlations between the overall stability index and VMS, and P1 and P2, as well as between the anteroposterior stability index and P1 and P2, were observed in the CAI patient group, but not in controls. Conclusion In patients with CAI, deficits in both quality of ankle arthrokinematic motion and postural control were present. Therefore, physical therapy interventions focused on improving ankle neuromuscular control and arthrokinematic function are necessary in CAI patient care. J Orthop Sports Phys Ther 2017;47(8):570-577. Epub 4 Nov 2016. doi:10.2519/jospt.2017.6836.

Number of knee and ankle injuries is associated with poor physical but not mental health

The knee and ankle are among the most commonly injured joints in the body. Long-term strength and neuromuscular control deficits are common following these injuries, yielding lifelong disability and poor quality of life. However, it is unknown how the number of injuries sustained influences quality of life.

OBJECTIVES

Determine the association between the number of ankle or knee injuries sustained and physical and mental quality of life.

METHODS

A total of 806 ankle-injured (age:45.2 ± 15.3 yrs; body mass index [BMI]:28.6 ± 7.4 kg/m²), 658 knee-injured (age:49.3 ± 16.1 yrs; BMI:28.4 ± 7.4 kg/m²), and 996 uninjured (age:43.4 ± 16.1 yrs; BMI:26.9 ± 6.5 kg/m²) adults completed the SF-8 survey to determine the physical (PCS) and mental (MCS) contributions to quality of life. Respondents were categorized by injury history (ankle, knee, none) and number of injuries (0, 1, 2, or 3 or more [3+]) to the same joint. Backward linear regression models were used to determine the association between quality of life, age, and injury history separately for SF-8 PCS and MCS, as well as ankle versus knee injury.

RESULTS

Reporting 1, 2, or 3+ ankle injuries along with age predicted SF-8 PCS (P < 0.001). Further, 1 or 2 ankle injuries and age (P < 0.001) predicted SF-8 MCS. Reporting 1, 2, or 3+ knee injuries along with age significantly predicted SF-8 PCS (P < 0.001). Age, but not knee injury history, significantly predicted SF-8 MCS (P < 0.001).

CONCLUSION

Current age and history of sustaining at least one injury negatively impact physical quality of life following either a knee or ankle injury. However, mental quality of life was predicted most consistently by age. Efforts to reduce injuries should be employed to improve quality of life, but more research is needed to determine what other factors contribute to quality of life across the lifespan.

Therapeutic interventions for improving self-reported function in patients with chronic ankle instability: a systematic review

OBJECTIVE

To identify which therapeutic intervention may be most effective for improving self-reported function in patients with chronic ankle instability (CAI).

DESIGN

Systematic literature review. Articles were appraised using the Downs and Black Checklist by 3 reviewers.

DATA SOURCES

PubMed along with CINAHL, MEDLINE and SPORTDiscus within EBSCOhost for pertinent articles from their inception through August 2016.

ELIGIBILITY CRITERIA FOR SELECTED STUDIES

Articles included were required to (1) be written in English, (2) report adequate data to calculate effect sizes, (3) identify patients with CAI, (4) use some form of therapeutic intervention and (5) use a self-reported questionnaire as a main outcome measurement.

RESULTS

A broad spectrum of therapeutic interventions were identified related to balance training, multimodal rehabilitation, joint mobilisation, resistive training, soft-tissue mobilisation, passive calf stretching and orthotics. All of the articles included in the balance training category had moderate-to-strong Hedges g with none of the 95% CIs crossing 0. Hedges g effect sizes ranged from -0.67 to -2.31 and -0.51 to -1.43 for activities of daily living and physical activity, respectively. The multimodal rehabilitation category also produced moderate-to-strong Hedges g effect sizes but with large CIs crossing 0. Hedges g effect sizes ranged from -0.47 to -9.29 and -0.62 to -24.29 for activities of daily living and physical activity, respectively.

CONCLUSIONS

The main findings from this systematic review were balance training provided the most consistent improvements in self-reported function for patients with CAI.

Foot and ankle ability measure to measure functional limitations in patients with foot and ankle disorders: a Chinese cross-cultural adaptation and validation

PURPOSE

To perform a cultural adaptation and validation study (internal and external) of the FAAM questionnaire to create the Chinese version of the questionnaire (FAAM-Ch).

MATERIALS AND METHODS

Two independent professional native translators performed a translation from English to Chinese and reverse translation. Psychometric properties analysis: Internal consistency of measure was analysed through the Cronbach's α coefficients. After extraction by maximum likelihood (EML), the structure factor and construct validity was analysed; to extract a factor, it was necessary to complete the following three requirements: ≥10% of variance, Eigenvalue >1.0 and scree plot inflection point. Standard error measurement (SEM) and minimal detectable change 90 (MDC90) were calculated. FFI-Taiwan version, SF12v2, and EuroQol5D were used for criterion validity analysis.

RESULTS

The internal consistency (Cronbach's α) for specific FAAM-Ch subscales was 0.879 (ADL) and 0.901 (Sport); test-retest analysis (interclass correlation) item ranging between 0.758 and 0.970 (ADL: 0758-0946; Sport: 0.911-0.970). Measures error: 3.449% (MDC90) and 1.478% (SEM). Chi-squared value =15228.74 and gl 406) (p < 0.001) and the Kaiser-Meyer-Oklin values (0.919). The correlation level with the FFI is strong, with SF12v2 is between poor and strong and with EuroQoL5d is between moderate and strong Conclusions: FAAM-Chinese version has satisfactory "transversal" psychometric properties, facilitating the inclusion of FAAM-Chinese into research and clinical practice. Implications for Rehabilitation Cross-cultural adaptation of the FAAM-Ch has been performed from the original version. The psychometric properties of the FAAM-Ch indicate satisfactory and consistent results (particularly in the internal consistence, reliability and criterion validity) with the original version. FAAM-Ch can be used by Chinese speaking clinicians and researches.

Relationships between mechanical joint stability and somatosensory function in individuals with chronic ankle instability

BACKGROUND

Individuals with chronic ankle instability (CAI) have demonstrated alterations in ankle mechanics and deficits in sensory function. However, relationships between mechanical stability and somatosensory function have not been examined, nor have those between somatosensory function and injury history characteristics. Therefore, the objective of this study was to examine relationships between (1) somatosensory function and mechanical stability and (2) somatosensory function and injury history characteristics.

METHODS

Forty adults with CAI volunteered to participate. In a single testing session, participants completed mechanical and sensory assessments in a counterbalanced order. Dependent variables included anterior/posterior displacement (mm), inversion/eversion rotation (°), SWM index values, JPS absolute error (°), number of previous ankle sprains, and number of "giving way" episodes in the previous 3 months. Spearman's Rho correlations examined the relationships between somatosensory function and (1) mechanical stability and (2) injury history characteristics (p<0.05).

RESULTS

No significant correlations were identified between any variables (p>0.11), and all r-values were considered weak.

CONCLUSIONS

These results revealed somatosensory function was not significantly correlated to mechanical stability or injury history characteristics. This indicates peripheral sensory impairments associated with CAI are likely caused by factors other than mechanical stability and injury history characteristics.

Evidence review for the 2016 International Ankle Consortium consensus statement on the prevalence, impact and long-term consequences of lateral ankle sprains

Lateral ankle sprains (LASs) are the most prevalent musculoskeletal injury in physically active populations. They also have a high prevalence in the general population and pose a substantial healthcare burden. The recurrence rates of LASs are high, leading to a large percentage of patients with LAS developing chronic ankle instability. This chronicity is associated with decreased physical activity levels and quality of life and associates with increasing rates of post-traumatic ankle osteoarthritis, all of which generate financial costs that are larger than many have realised. The literature review that follows expands this paradigm and introduces emerging areas that should be prioritised for continued research, supporting a companion position statement paper that proposes recommendations for using this summary of information, and needs for specific future research.

2016 consensus statement of the International Ankle Consortium: prevalence, impact and long-term consequences of lateral ankle sprains

The Executive Committee of the International Ankle Consortium presents this 2016 position paper with recommendations for information implementation and continued research based on the paradigm that lateral ankle sprain (LAS), and the development of chronic ankle instability (CAI), serve as a conduit to a significant global healthcare burden. We intend our recommendations to serve as a mechanism to promote efforts to improve prevention and early management of LAS. We believe this will reduce the prevalence of CAI and associated sequelae that have led to the broader public health burdens of decreased physical activity and early onset ankle joint post-traumatic osteoarthritis. Ultimately, this can contribute to healthier lifestyles and promotion of physical activity.

Corticospinal Excitability and Inhibition of the Soleus in Individuals With Chronic Ankle Instability

BACKGROUND

Understanding the mechanisms of neurophysiological alterations with chronic ankle instability (CAI) may be essential in the development of the most-effective intervention programs to treat neuromuscular dysfunction in patients with CAI. Specifically, the presence of CAI may be associated with an altered supraspinal mechanism within the central nervous system to inhibit neural drive to the undamaged soleus surrounding the injured ankle joint.

OBJECTIVE

To investigate the influence of CAI on corticospinal excitability and inhibition of the soleus.

DESIGN

A single-blinded, case-control study.

SETTING

Research laboratory.

PARTICIPANTS

Sixteen participants with self-reported CAI and 17 healthy control participants volunteered.

METHODS

Transcranial magnetic stimulation was used to assess corticospinal excitability and inhibition of the soleus muscle. Active motor threshold (AMT), defined as the lowest stimulator intensity required to elicit a peak-to-peak motor-evoked potential (MEP) amplitude ≥100 μV in at least four of 8 trials, was found to assess corticospinal excitability of the soleus. Eight stimuli were delivered at 120% of AMT, and peak-to-peak MEP amplitudes were recorded for each trial. The amplitude of 8 MEPs at 120% of AMP were averaged and normalized to the maximum M-response. Cortical silent period (CSP) was measured as the distance from the end of the MEP to a return of the mean electromyographic signal plus 2 times the standard deviation of the baseline (prestimulus) electromyographic signal. The ratio of the CSP to the MEP at 120% AMT (CSP:MEP₁₂₀) were calculated to assess corticospinal inhibition.

RESULTS

The CAI group had a greater CSP:MEP₁₂₀ ratio compared with the control group (P = .02). No significant differences between groups were observed for AMT (P = .67) and normalized MEP at 120% of AMT (P = .42).

CONCLUSIONS

The greater CSP:MEP₁₂₀ ratio in participants with CAI suggests an altered balance in corticospinal inhibition and excitability to the soleus of the CAI cohort. Future research is needed to determine the role of corticospinal inhibition in physical and self-reported function in patients with CAI.

LEVEL OF EVIDENCE

IV.

The Consequence of a Medial Ankle Sprain on Physical and Self-reported Functional Limitations: A Case Study Over a 5-Month Period

STUDY DESIGN

Case report.

BACKGROUND

Little evidence exists about impairments and perceived disability following eversion injury to the deltoid ligament. This case study prospectively examined the neuromuscular, biomechanical, and psychological consequences of a case of a medial ankle sprain.

CASE DESCRIPTION

A recreationally active man with a history of a lateral ankle sprain (grade I) was participating in a university Institutional Review Board-approved research study examining the neuromuscular and mechanical characteristics associated with chronic ankle instability. Twenty-two days after the testing session, the participant sustained an eversion injury to his left ankle while playing basketball. Outcomes The outcomes of this case are presented using the International Classification of Functioning, Disability and Health model. Outcome variables were assessed at preinjury (medial ankle sprain), 3 months postinjury, and 5 months postinjury. Measurements included neural excitability of the soleus, balance assessment, joint stability, and psychological assessments. Data from this case study revealed that a medial ankle sprain reduces joint mobility and alters neural excitability of the soleus, with concurrent deficits in balance and self-reported function. These impairments forced the participant to downgrade his physical activity lifestyle up to 5 months postinjury.

DISCUSSION

These data suggest the need for the development of intervention strategies to address impairments in neural excitability and joint mobility at the ankle to help patients meet the goal of maintaining long-term joint health.

LEVEL OF EVIDENCE

Prognosis, level 4.

Contributing factors to star excursion balance test performance in individuals with chronic ankle instability

The purpose of this study was to determine the contributions of strength, dorsiflexion range of motion (DFROM), plantar cutaneous sensation (PCS), and static postural control to Star Excursion Balance Test (SEBT) performance in individuals with chronic ankle instability (CAI). Forty individuals with CAI completed isometric strength, weight-bearing DFROM, PCS, static and dynamic balance assessments. Three separate backward multiple linear regression models were calculated to determine how strength, DFROM, PCS, and static postural control contributed to each reach direction of the SEBT. Explanatory variables included dorsiflexion, inversion, and eversion strength, DFROM, PCS, and time-to-boundary mean minima (TTBMM) and standard deviation (TTBSD) in the medial-lateral (ML) and anterior-posterior (AP) directions. Criterion variables included SEBT-anterior, posteromedial, and posterolateral directions. The strength of each model was determined by the R2-value and Cohen's f2 effect size. Regression models with an effect size ≥0.15 were considered clinically relevant. All three SEBT directions produced clinically relevant regression models. DFROM and PCS accounted for 16% of the variance in SEBT-anterior reach (f2=0.19, p=0.04). Eversion strength and TTBMM-ML accounted for 28% of the variance in SEBT-posteromedial reach (f2=0.39, p<0.01). Eversion strength and TTBSD-ML accounted for 14% of the variance in SEBT-posterolateral reach (f2=0.16, p=0.06). DFROM and PCS explained a clinically relevant proportion of the variance associated with SEBT-anterior reach. Eversion strength and TTB ML explained a clinically relevant proportion of the variance in SEBT-posteromedial and posterolateral reach distances. Therefore, rehabilitation strategies should emphasize DFROM, PCS, eversion strength, and static balance to enhance dynamic postural control in patients with CAI.