External Versus Internal Feedback in Patients With Chronic Ankle Instability

Study Overview
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Brief Summary
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Although altered biomechanics has been well documented as an impairment associated with chronic ankle instability (CAI), effective interventions targeting biomechanics with long-term outcomes measuring patient-reported outcomes (PROs) are absent. Evidence suggests that external focus of attention (ExFOCUS), internal focus of attention (InFOCUS) feedback, and auditory feedback during movement training can alter biomechanics in other patient populations, with ExFOCUS and auditory enhancing retention of learned biomechanics. Therefore, this randomized controlled trial will determine if a 4-week (12 session) impairment-based rehabilitation program that includes feedback (ExFOCUS or InFOCUS or Auditory) can (1) decrease ankle inversion kinematics and lateral plantar pressure during walking and (2) improve self-reported function.

Official Title
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External Versus Internal Feedback on Biomechanics and Self-reported Function in Patients With Chronic Ankle Instability

Conditions
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Ankle Injuries, Ankle Inversion Sprain

Intervention / Treatment
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* Other: External focus of attention visual feedback
* Other: External focus of attention auditory feedback
* Other: Internal focus of attention video feedback
* Other: No feedback


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Characterized as having chronic ankle instability (CAI) by reporting a history of recurrent ankle sprains, with the first sprain occurring longer than 12 months ago. Participants will have lingering symptoms, and disability, but have not actively sought treatment for their CAI. All participants will be physically active: Participating in some form of physical activity for at least 20 min per day, three times per week. Exclusion Criteria: Neurological or vestibular disorders affecting balance Currently seeking medical care for CAI History of ankle surgery History of ankle sprain within the past 6 weeks History of other musculoskeletal injuries within the past 6 weeks Current/previous self-reported disability due to lower extremity pathology that may adversely affect neuromuscular function

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ExFOCUS Visual<br>Participants will complete 12 sessions over 4-weeks of impairment-based rehabilitation that incorporates ankle range of motion, ankle strength, balance, and functional activity exercises. For the balance and functional activity exercises, participants will use traditional instability tools and will receive external focus of attention visual feedback. | Other: External focus of attention visual feedback<br>* Patients will receive external focus of attention visual feedback during the impairment-based rehabilitation program.<br>|
| Experimental: ExFOCUS Auditory<br>Participants will complete 12 sessions over 4-weeks of impairment-based rehabilitation that incorporates ankle range of motion, ankle strength, balance, and functional activity exercises. For the balance and functional activity exercises, participants will use traditional instability tools and will receive auditory feedback. | Other: External focus of attention auditory feedback<br>* Patients will receive external focus of attention auditory feedback during the impairment-based rehabilitation program.<br>|
| Experimental: InFOCUS Visual<br>Participants will complete 12 sessions over 4-weeks of impairment-based rehabilitation that incorporates ankle range of motion, ankle strength, balance, and functional activity exercises. For the balance and functional activity exercises, participants will use traditional instability tools and will receive internal focus of attention visual feedback via video. | Other: Internal focus of attention video feedback<br>* Patients will receive internal focus of attention visual feedback during the impairment-based rehabilitation program.<br>|
| Active Comparator: NoFeedback<br>Participants will complete 12 sessions over 4-weeks of impairment-based rehabilitation that incorporates ankle range of motion, ankle strength, balance, and functional activity exercises. For the balance and functional activity exercises, participants will use traditional instability tools and receive no feedback. | Other: No feedback<br>* Patients will receive no feedback during the impairment-based rehabilitation program.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes from baseline in lower extremity kinematics and kinetics during walking | Ankle, knee, and hip motion and moments during walking measured by a 3D motion capture system and in shoe plantar pressure system | Immediate post-intervention, 1-month post-intervention, 3-months post-intervention | 
| Changes from baseline in self-reported ankle function | Changes from baseline in self-reported function as measured by the Foot and Ankle Ability Measure (FAAM) Activities of Daily Living and Sport questionnaire. Scores range from 100% (no decrease in function) to 0% (complete loss of function). | Immediate post-intervention, 1-month post-intervention, 3-months post-intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes from baseline in ankle range of motion measured in degrees | Four different ankle ranges of motion will be measured | Immediate post-intervention, 1-month post-intervention, 3-months post-intervention | 
| Changes from baseline in ankle maximum voluntary isometric strength | Ankle maximum voluntary isometric strength will be measured during four different ankle positions using a hand-held dynamometer. | Immediate post-intervention, 1-month post-intervention, 3-months post-intervention | 
| Changes from baseline in static and dynamic balance | Static balance will be measured via a force plate and dynamic balance will be measured using the Star Excursion Balance Test | Immediate post-intervention, 1-month post-intervention, 3-months post-intervention |