Efficacy of BFR Training Combined With Eccentric Exercise as Assessed by SWE in Subjects With Chronic AT

Study Overview
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Brief Summary
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The purpose of this randomized controlled trial is to use Shear Wave Elastography (SWE) to assess Achilles tendinopathy and the effectiveness of Blood Flow Restriction (BFR) training in patients with Achilles tendinopathy as measured by Numeric Pain Rating Scale, functional self-report, and objective functional measures. SWE will be utilized to objectively quantify tendon properties and BFR training and eccentric exercise will be utilized to treat Achilles tendinopathy.

Official Title
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Efficacy of Blood Flow Restriction Training Combined With Eccentric Exercise as Assessed by Shear Wave Elastography in Subjects With Chronic Achilles Tendinopathy: A Randomized Single Blinded Controlled Trial

Conditions
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Achilles Tendinopathy

Intervention / Treatment
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* Other: Blood Flow Restriction Training
* Other: Sham Blood Flow Restriction Training
* Other: Eccentric Exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Achilles pain for > 3 months Unilateral symptoms only DOD beneficiary, between the ages of 18 and 65 Clinical diagnosis of Achilles tendinopathy Read and speak English well enough to provide informed consent and follow study instructions. Can attend in-clinic treatments 2-3 x weekly for the next 12 weeks Exclusion Criteria: Any disease or disease process that would preclude the participant from safely performing any of the exercises or intervention at the discretion of the PI. (Uncontrolled diabetes, cardiac disease, severe COPD, open wounds, current infection, etc.) Any LE surgery on either side in the last 2 years History of Achilles rupture Any vascular disorder (varicose veins, Hx of DVT) Leaving post/station in the following 3 months precluding them being able to come in for f/u visits Self-report of pregnancy (currently or within last 6 months) Other foot/LE disorder that prevents the completion of the eccentric exercises or BFR exercise Unable/unwilling to hop on symptomatic leg Pain < 2/10 of average pain on NPRS VISA A score > 80% Currently going through MEB/worker's comp

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: BFR Group<br>Blood Flow Restriction Training with Eccentric Exercise Protocol | Other: Blood Flow Restriction Training<br>* Delfi Personalized Tourniquet System occludes 80% venous pressure during lower extremity exercise.<br>Other: Eccentric Exercise<br>* Subjects perform eccentric calf lowering off a step for 90 repetitions twice daily.<br>|
| Sham Comparator: Sham BFR Group<br>Sham Blood Flow Restriction Training with Eccentric Exercise Protocol | Other: Sham Blood Flow Restriction Training<br>* Delfi Personalized Tourniquet System occlude 20 mmHG venous pressure during lower extremity exercise as a sham treatment.<br>Other: Eccentric Exercise<br>* Subjects perform eccentric calf lowering off a step for 90 repetitions twice daily.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Shear Wave Elastography velocity | Difference between involved and uninvolved Achilles tendon | At baseline. | 
| VISA-A | Change in subjective self-report of Achilles function | From baseline to 24 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Triple hop test | Distance in length of 3 consecutive hops on one foot | At baseline, then at 3 weeks, 6 weeks, 9 weeks, and 12 weeks. | 
| SL Calf Raise Endurance | Number of single leg calf raises to failure | At baseline, then at 3 weeks, 6 weeks, 9 weeks, and 12 weeks. | 
| SL Jump Height | Distance in height of single leg jump | At baseline, then at 3 weeks, 6 weeks, 9 weeks, and 12 weeks. | 
| Thigh Circumference | circumferential measurement of thigh | At baseline, then at 3 weeks, 6 weeks, 9 weeks, and 12 weeks. | 
| Calf Circumference | circumferential measurement of calf | At baseline, then at 3 weeks, 6 weeks, 9 weeks, and 12 weeks. | 
| Numerical Pain Rating Scale | Pain level on a 0 to 10 scale | At baseline, then at 3 weeks, 6 weeks, 9 weeks, 12 weeks and 24 weeks. | 
| Global Rating of Change | 15 point Likert scale from -7 to +7 | At 3 weeks, 6 weeks, 9 weeks, 12 weeks and 24 weeks. | 
| Shear Wave Elastography velocity | Change in shear wave elastography of symptomatic Achilles tendon over time. | Baseline, at 3 weeks, 6 weeks, 9 weeks, 12 weeks. |