Tag: cai

Proprioception and Postural Control: Clinical Insights from Recent Research

Leave a comment

Blog Post Author Biography: Dr. Brice Picot currently works at the Sciences et Technologies des Activités Physique et Sportives (STAPS), Université Savoie Mont Blanc and in the French association of Sports Physical Therapy. Brice does research in Traumatology, Rehabilitation Medicine and Physiotherapy. His current projects are focused on injury rehabilitation and prevention of Chronic Ankle Instability and ACL among athletes.

Citation: Sagnard T, Picot B, Forestier N. Proprioceptive acuity, proprioceptive weighting and balance in individuals with chronic ankle instability. Gait Posture. Published online March 15, 2025. doi:10.1016/j.gaitpost.2025.03.006

Take-to-the-Clinic Message:

  • Not all patients suffering from CAI exhibits postural impairments or proprioceptive acuity and reweighting deficits.
  • Poorer proprioceptive acuity is associated with increases postural sway, only in CAI patients.
  • Higher proprioceptive reweighting is observed when proprioception is disrupted in healthy individuals only.

Background: Chronic ankle instability (CAI) is a common consequence of repeated ankle sprains, often leading to impaired postural control and proprioception. Understanding the impact of these deficits is crucial for improving rehabilitation strategies.

Purpose: The purposes of this study were to evaluate proprioceptive and postural control deficits among CAI and healthy control individuals, and to assess whether these parameters were correlated among those two groups.

Methods: The study assessed 13 participants with chronic ankle instability (CAI) and 15 healthy controls to examine proprioception and balance deficits. Joint position sense (JPS) was evaluated in dorsiflexion and plantarflexion by calculating absolute and constant repositioning errors. Unipedal balance was measured using center of pressure (CoP) ellipse area and velocity to assess postural stability. Relative proprioceptive weighting (RPW) was determined by analyzing postural responses to triceps surae and lumbar multifidus tendinous vibrations.

Results: This study found nodifferences in proprioception or balance between CAI patients and healthy controls. However, within the CAI group, poorer accuracy in proprioceptive acuity was linked to greater difficulty maintaining balance, as shown by increased body sway. In contrast, for the control group, a different relationship emerged—those with greater proprioceptive errors tended to rely more on other sensory inputs for balance.

Rolling the field forward: Contrary to previous belief, not all CAI patients exhibited poor postural control or impaired proprioception. However, results from the present study suggests that contrary to healthy individuals, people with CAI still maintain an ankle steered strategy when proprioceptive signals are inaccurate. This could explain why CAI patients with unreliable acuity (i.e. high errors in JPS) exhibit poorer postural control while healthy control individuals do not. These findings highlight the importance of assessing both proprioception and balance in CAI patients to better address potential deficits in rehabilitation programs.

Question for the researchers:

  • How can we easily evaluate postural control deficits in CAI patients?
  • What are the normative values in errors of repositioning among healthy individuals?

External Ankle Support and Ankle Biomechanics in Chronic Ankle Instability

Leave a comment

Blog Post Author Biography: Patrick Rowe is a Physiotherapist, Lecturer & PhD Candidate in the College of Sport, Health & Engineering at Victoria University and the Centre of Health, Exercise & Sports Medicine at the University of Melbourne. Patrick has research expertise in the biomechanics of lateral ankle sprains and chronic ankle instability by using musculoskeletal modeling to explore how footwear and external ankle supports influence the lateral ankle ligament complex.

Citation: Rowe, P. L., Bryant, A. L., Egerton, T. & Paterson, K. L. External ankle support effects on ankle biomechanics in chronic ankle instability: systematic review and meta-analysis. Journal of Athletic Training (2022) doi:10.4085/1062-6050-0208.22.

Take-to-the-clinic message: This review found that ankle supports (taping and bracing) reduce inward motion but not inward position at ground contact in people with unstable ankles during landing. This may help prevent ankle sprains or lessen injury severity by limiting excessive inward movement. However, while ankle supports also reduce forward ankle motion, this could shift forces to the knee and hip, potentially increasing injury risk at these joints.

Background: Lateral ankle sprains are common among youth and adolescent athletes in high-demand, multidirectional sports, with up to 70–80% experiencing repeated sprains and chronic ankle instability (CAI). Biomechanical alterations in CAI, such as reduced plantarflexion and higher ground reaction forces during landing, contribute to instability. Athletes often use ankle supports (taping and bracing) to reduce sprain risk, but research is limited to non-randomized studies and lower-demand tasks. Therefore, we must explore whether external ankle supports influence ankle biomechanics during higher demand tasks (running, landing, and cutting), particularly in athletes at higher risk of sustaining a lateral ankle sprain and CAI.

Purpose: This systematic review aimed to compare the effects of external ankle supports compared to no support on ankle biomechanics in individuals with CAI during sports-related tasks.

Methods: This systematic review followed the Cochrane Handbook, PICOT framework, and PRISMA 2020 guidelines and was registered with PROSPERO in August 2020. A comprehensive search of MEDLINE, SPORTDiscus, and CINAHL in November 2021 identified randomized controlled or crossover studies on ankle biomechanics in individuals with CAI using external supports during landing, running, and directional changes. Studies were independently assessed for eligibility, appraised using the Cochrane risk-of-bias tool, and analyzed using random-effects meta-analysis with 95% confidence intervals.

Results: The literature search identified 162 studies, with 13 meeting inclusion criteria, totaling 248 CAI participants. Most studies had low to moderate risk of bias and examined various ankle supports, including non-elastic taping, semi-rigid bracing, soft bracing, and elastic taping. Landing (7 studies) and running (5 studies) were most commonly investigated, while change of direction tasks lacked homogenous data for meta-analysis. External ankle supports did not reduce inversion angle at initial contact during landing or running but showed very low-grade evidence of reducing frontal-plane and sagittal-plane excursion. These findings suggest ankle supports may influence some biomechanical aspects but with limited evidence supporting their overall effectiveness.

Rolling the field forward: This novel review provides further insight into how external ankle supports influence ankle biomechanics during high demand tasks, and the current literature suggests that external ankle support do not influence ankle inversion position prior to ground contact during running and landing. This challenges the current perception of the mechanical function of external ankle supports which is traditionally thought to adjust ankle inversion position during the pre-landing phase. In contrast, frontal plane excursion was found to be significantly reduced, which may be an important consideration for a typical lateral ankle sprain mechanism by limiting excessive inversion kinematics. Another major finding was the significant reduction in sagittal plane kinematics during running and landing. This may be considered either beneficial or detrimental due changes in ankle position (close-packed) or proximal loading at the hip and knee joints. However, it is difficult to determine this effect based on the limited evidence currently available. Future research should consider validated musculoskeletal, multi-segmental foot and ankle models to accurate measures to quantify joint kinematics, kinetics, joint contact, muscle, and ligament forces during high-demand sporting tasks. Adopting more sophisticated laboratory-based biomechanical approaches for CAI research will provide better translation to clinical and sporting environments and assist in reducing the burden of lateral ankle sprains.

Question for researchers: Based on the kinematic alterations of external ankle supports, does this lead to changes in tissue-based strains and forces at the lateral ankle ligament complex? In turn, do ankle-spanning musculotendinous structures perform differently during higher demand tasks when frontal and sagittal plane kinematics are limited? As a consequence of sagittal plane restrictions, do external ankle supports have negative implications to proximal structures (ie. knee) such as joint contact (tibiofemoral) and ligament (ACL) forces?

Sensory Reweighting System Differences on Vestibular Feedback with Increased Task Constraints

Leave a comment

Blog Post Author Biography: Yuki Sugimoto is an Assistant Professor in the Department of Physical Therapy & Human Movement Science at the Feinberg School of Medicine, Northwestern University, and has a clinical background as a certified athletic trainer. One of Dr. Sugimoto’s research interests is the sensory reweighting system and changes in reliance on visual and vestibular feedback in individuals with chronic ankle instability.

Citation: Sugimoto YA, McKeon PO, Rhea CK, et al. Sensory Reweighting System Differences on Vestibular Feedback With Increased Task Constraints in Individuals With and Without Chronic Ankle Instability. J Athl Train. 2024;59(7):713-723. doi:10.4085/1062-6050-0246.22

Take-to-the-clinic message: The results highlight the importance of considering vestibular feedback reliance during postural control assessment and rehabilitation in individuals with chronic ankle instability (CAI). Combining tests such as the horizontal head impulse test with single-limb postural assessments may reveal underlying sensory reweighting dysfunction, especially under varying environmental and task conditions. Clinicians should explore multisensory feedback approaches that challenge vestibular function to improve rehabilitation outcomes in individuals with CAI.

Background: Postural stability is critical for motor behavior in dynamic environments and relies on the ability to reweight sensory feedback from somatosensory, visual, and vestibular systems as environmental and task constraints change. Individuals with CAI may have sensory reweighting deficits, leading to an over-reliance on visual feedback and difficulties maintaining postural control, especially in complex tasks like single-limb stance. However, current evidence suggests that somatosensory feedback contributions to postural control in individuals with CAI cannot be ruled out based solely on balance scores in single-limb stance with and without eyes closed. In addition, the sensory reweighting system in individuals with CAI and whether they upweight visual feedback to maintain posture in bilateral and unilateral (uninjured, injured) stances compared to healthy individuals remains unknown.

Purpose: The primary purpose of the study was to examine the sensory reweighting system changes to control posture in a simple double-limb stance and a more complex uninjured- or injured-limb stance under increased environmental constraints, manipulating somatosensory and visual information, for individuals with and without CAI. The secondary purpose of the study was to determine the effect of environmental and task constraints on postural stability.

Methods: The study included 42 physically active individuals with and without unilateral CAI. Participants completed postural control assessments using the Sensory Organization Test (SOT) on a NeuroCom dynamic posturography platform, which measures the ability to integrate somatosensory, visual, and vestibular feedback across six conditions of varying complexity. Equilibrium balance scores were calculated based on center-of-gravity sway, and sensory reweighting ratios were determined to assess the weighting of different sensory systems.

Results: The study is the first investigation of how the sensory reweighting system adapts to control posture under increased task constraints and how postural control is influenced by both environmental and task constraints in individuals with and without CAI. Notably, the CAI group did not reduce their reliance on vestibular feedback when standing on the injured limb. However, the inability to downweight vestibular feedback may represent a compensatory reliance for individuals with CAI, as they maintained postural stability on the injured limb better than healthy controls. Both groups showed different patterns of sensory feedback use depending on the task. Somatosensory input was the most emphasized during double-limb stance, whereas visual feedback was prioritized during single-limb stance in both injured and uninjured limbs. Differences in postural control between groups were shaped by task and environmental demands, although individuals with CAI demonstrated postural control similar to that of healthy participants.

Rolling the field forward: This research demonstrates that while individuals with CAI do not downweight vestibular feedback to maintain posture on their injured limb, this reliance may serve as a compensatory mechanism, allowing them to maintain better postural stability than those without CAI. In addition, postural control in both groups was influenced by the specific sensory systems engaged and the constraints imposed by the task. Clinicians should consider using a multisensory feedback approach in their interventions, challenging vestibular input, with and without visual cues, during tasks with increased demands to improve postural control for individuals with CAI.

Question for the researchers: How might clinicians implement multisensory feedback approaches in rehabilitation programs to specifically address the compensatory reliance on vestibular feedback observed in individuals with CAI?

Dual-Task Postural Control Assessment in Individuals with Chronic Ankle Instability

Leave a comment

Blog Post Author Biography: Dr. Matthew Hoch is a Professor in the Department of Athletic Training and Clinical Nutrition and the Senior Associate Director for the Sports Medicine Research Institute at the University of Kentucky. Dr. Hoch’s interests include the investigation of rehabilitation interventions for patients with chronic ankle instability.

Citation: Choi JY, Yoo T, Burcal CJ, Rosen AB. Dual-task differences in individuals with chronic ankle instability: A systematic review with meta-analysis. Gait Posture. 2023; 106(28-33). DOI: 10.1016/j.gaitpost.2023.08.013

Take-to-the-clinic message: The clinical utility of dual-task assessments is continually evolving for an array of sports medicine applications. This meta-analysis sought to examine the ability of dual-task balance and gait assessments to identify performance deficits in people with chronic ankle instability. The literature to date is unable to consistently identify balance or gait deficits using dual-task testing paradigms. However, trends in the data suggest that further examining dual-task assessments utilizing more challenging tasks may yield different insights.

Background: Ligamentous injuries, such as lateral ankle sprains, create complex sensorimotor alterations which often manifest clinically as impairments in postural control and gait. Understanding the interaction of cognitive and sensorimotor function using dual-task assessments has emerged as a potential area to advance care for musculoskeletal conditions. Several studies have applied dual-task balance and gait assessments to assess performance in people with chronic ankle instability. However, the conclusiveness of these studies is difficult to determine without more advanced analysis.

Purpose: The purpose of this systematic review and meta-analysis was to determine differences in dual-tasking assessing gait and postural control in individuals with chronic ankle instability compared to healthy controls.

Methods: This systematic review and meta-analysis searched for articles using multiple relevant databases from inception through 2022. Peer-reviewed observational studies which incorporated single- and dual-task assessments to study motor performance related to gait, balance, or other functional performance outcomes in patients with a history of ankle sprain or chronic ankle instability along with either a healthy reference group or limb were included. Two reviewers applied the 22-item Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement to assess risk of bias and methodological quality of the included studies. Separate, random effect meta-analyses were used to evaluate mediolateral and anteroposterior directions of balance-related outcomes. Additional supporting analyses were applied to evaluate heterogeneity and potential bias from unpublished studies.

Results: A total of nine studies were included in the systematic review. Five studies met the requirements to be included in the meta-analysis. The average STROBE score was 13.3±3.8 indicating a moderate level of study quality. Six the included studies examined dual-task balance while three focused on dual-task gait. The results of the meta-analyses determined that dual-tasking affected postural control outcomes in the control group. However, no differences were identified in the chronic ankle instability group or when comparing healthy and chronic ankle instability groups.

Rolling the field forward: The primary finding of this study was that dual-tasking did not significantly impact postural control outcomes in individuals with chronic ankle instability. However, trends within the available data indicated that studies applying more challenging balance tasks demonstrated trends towards poorer postural control under the dual-task condition. This indicates that future studies and clinical investigations should explore coupling dual-task balance assessments or exercises with more challenging and potentially dynamic balance tasks. This systematic review was only able to identify three studies which examined dual-task gait in chronic ankle instability patients and identified mixed results. The application of dual-task gait requires additional study before strong recommendations can be made. Cumulatively, this study suggests that the field may need to explore different mechanisms to effectively integrate dual-task paradigms into the clinical management for patients with a history of ankle sprain.

Question for the researchers: Many of the included studies used an approach to dual-tasking by adding cognitive load through tasks such as serial subtraction. Do you think utilizing cognitive challenges associated with greater demand on sensory integration or decision making could produce different results in patients with a history of ankle sprain or instability?

Participant-Level Improvements in Health-Related Quality of Life in Those With Chronic Ankle Instability

Leave a comment

Blog Post Author Biography: Dr. Cameron Powden is an Associate Professor in the Department of Athletic Training at the University of Indianapolis. Dr. Powden’s interests include the investigation of clinically relevant interventions for ankle sprains and chronic ankle instability.

Citation: Powden CJ, Koldenhoven RM, Simon JE, et al. Participant-Level Analysis of the Effects of Interventions on Patient-Reported Outcomes in Patients With Chronic Ankle Instability. Journal of Sport Rehabilitation. 2023;32(2):124-132. DOI: 10.1123/jsr.2022-0053

Take-to-the-clinic message: This investigation matches previous literature indicating that the available chronic ankle instability (CAI) interventions are capable of improving self-reported ankle function, global well-being, and injury-related fear at the group level for patients with CAI. This study uniquely assessed individual level responses of patients with CAI to multimodal interventions. Between 13.8% and 53.3% of patients demonstrated improvements, for individual patient-reported outcomes (PROs), that exceeded the minimal detectable change (MDC) of the measure. These findings signify that individually, we may hope to only have about half of our patients have meaningful improvements following intervention.

Background: CAI intervention studies have often focused on improving physical impairments of the ankle complex. Recently, increased emphasis has been placed on the sensory-perceptual impairments associated with CAI. This has resulted in CAI investigations examining the health-related quality of life (HRQoL) through PROs of those with CAI, and the influence of intervention on such PROs. While most studies have assessed self-reported ankle function and through the lens of group level response, there is a need to investigate the impact of interventions on other aspects of HRQoL (such as global well-being and injury-related fears) and the individual level response to treatment within those with CAI.

Purpose: To evaluate improvements in multiple domains of HRQoL, self-reported ankle function, global well-being, and injury-related fear, following multimodal interventions in patients with CAI by using group- and participant-level responder analyses.

Methods: A secondary analysis was completed on a compiled data set of original, participant-level data from seven previously published investigations. Each of the investigations investigated self-reported function in patients with CAI. A total of 136 physically active individuals with self-reported CAI were included in the analysis. These individuals underwent a wide range of multimodal interventions that ranged from 1 to 6 weeks in length, 1 to 12 supervised sessions, and may have included a home intervention component. PROs included were the Foot and Ankle Ability Measure (FAAM) ADL and Sport, Tampa Scale of Kinesiophobia-11 (TSK-11), Fear Avoidance Belief Questionnaire (FABQ) and the Disablement in the modified Physically Active Scale (mDPA) physical summary component (PSC) and the mental summary component (MSC). The research team examined preintervention to postintervention changes in each PRO, as well as effect sizes (ES) and individual-level response rates through changes exceeding published MDCs.

Results: There was significant improvement in ankle-specific function following intervention that was associated with strong ESs and responder rates of 39.0% to 53.3%. There was a significant reduction in injury-related fear following intervention that was associated with moderate to strong effects and responder rates of 13.8% to 51.4%. Finally, there was a significant improvement in global well-being that was associated with strong effects and responder rates of 31.3%. 

Rolling the field forward: This investigation is part of the expanding evidence regarding interventions for those with CAI. It builds on previous multimodal intervention studies by combining various intervention protocols to allow for robust group and individual level analysis. The findings indicate that patients with CAI exhibit holistic HRQoL improvements following varied interventions. This investigation continues the exploration into individual-level responses within the CAI population. Further research is needed to better understand the clinical impact of this new form of analysis. Lastly, to enhance the ability to examine CAI interventions, at the group and individual level, there is a need to identify common clinician-, laboratory-, and patient-oriented outcome measures to allow for robust and comparative analysis.

Question for the researchers: What interventions would be beneficial for CAI patients to enhance aspects of HRQoL? How do researchers and clinicians work to develop common outcome measures to explore? Can the individual level responder analysis be used in clinical practice to examine patient progress?

Impact of Electrical Stimulation with Balance Training in those with CAI

Leave a comment

Blog Post Author Biography: Alan Needle is a Professor at Appalachian State University in the Department of Public Health and Exercise Science and the Department of Rehabilitation Sciences. He has been a certified and licensed athletic trainer since 2007, and conducts research related to assessing and treating neurological impairments in individuals with ankle sprains and chronic ankle instability.

Citation: Gottlieb U, Hayek R, Hoffman JR, Springer S. Exercise combined with electrical stimulation for the treatment of chronic ankle instability – A randomized controlled trial. J Electromyogr Kines. 2024; 74: 102856. https://doi.org/10.1016/j.jelekin.2023.102856.

Take-to-the-clinic message: Combining neuromuscular electrical stimulation with balance exercises improved long-term ankle function in individuals with chronic ankle instability better than therapeutic exercise combined with transcutaneous electrical nerve stimulation. These effects were observed with 12 total treatment sessions over 4-6 weeks, with improvements seen at 6 and 12 months following the intervention.

Background: While therapeutic exercises are a common method for treating individuals with chronic ankle instability (CAI), continued high rates of re-injury and many required treatment sessions creates a need for manners to augment CAI rehabilitation. In individuals with ACL injury, forms of electrical stimulation, including transcutaneous electrical nerve stimulation (TENS) and neuromuscular electrical stimulation (NMES) are often implemented to address neurological changes following injury. TENS and NMES have shown limited efficacy in individuals with CAI; however, it is unclear how they would affect function when combined with therapeutic exercise.

Purpose: This study aimed to assess the short, medium, and long-term effects of balance training in conjunction with NMES or TENS on dynamic postural control and patient-reported outcome measures.

Methods: This study implemented a double-blind randomized controlled trial design conducted in 34 young adults with CAI, following International Ankle Consortium guidelines. Participants were randomized into groups receiving NMES or TENS over the peroneal (fibularis) muscles, while all individuals conducted ankle rehabilitation exercises emphasizing static and dynamic balance. Outcome measures included dynamic balance conducted through a Y-balance test and time-to-stabilization from a single-leg drop jump. Patient function was quantified through the Foot and Ankle Ability Measure (FAAM) activities of daily living (FAAM-ADL) and sport subscales (FAAM-Sport), as well as the Cumberland Ankle Instability Tool (CAIT) and Identification of Functional Ankle Instability (IdFAI) instrument. Participants were instructed on performing the balance exercises and operation of a portable electrical stimulation device, with exercises being conducted during active stimulation. Participants performed 12 total treatment sessions over a period of 4 to 6 weeks, with follow-up immediately, 6-months, and 12-months following the intervention.

Results: Of the 34 individuals who enrolled in the study, 10 out of 14 participants in the NMES group completed the study, while 14 out of 15 participants in the TENS group completed the study. Patient-reported outcome measures improved across both groups at the 12-month follow-up. The NMES group showed improvements beyond the TENS group at 6 and 12 months for the IdFAI and FAAM-Sport measures. Large, but non-significant effects were observed in dynamic balance measures following the intervention.

Rolling the field forward: The researchers in this study explored how augmenting rehabilitation with treatments designed to be neuromodulatory (i.e. improve muscle reflexive actions) may improve clinician- and patient-oriented measures of function. The results showed improved long-term improvements in perceived disease-oriented function in individuals that received exercise and NMES, compared to those receiving exercise and TENS, with these improvements being in disease-oriented outcomes (IdFAI) and those reflecting more challenging function (FAAM-Sport). Importantly, these outcomes were achieved with a program carried out at home.

Question for the researchers: Do the authors feel that balance exercises were the ideal therapeutic exercise to pair with the NMES and TENS interventions? Given the programming needed on the stimulators, what steps would be needed to make this treatment more accessible to the average practicing clinician?