Measures of Gait Efficiency of Three Multi-Axial, Vertical Shock and Energy Storing-Return Prosthetic Feet During Simple & Complex Mobility Activities

Study Overview
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Brief Summary
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Many service members suffering major limb amputation(s) during active duty seek to return to active duty. The purpose of this study is to determine if biomechanic and/or bioenergtic differences exist between popular multi-function prosthetic feet that would facilitate return to duty for soldiers with amputations.

Detailed Description
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Specific Aims Compare the effectiveness of popular prostheses for improving performance in physically demanding tasks and environments. Compare amputee performance to a group of high-functioning non-amputees to determine performance differences between the groups. Hypotheses: Prosthetic feet with shock absorbing and torsional features will perform better in field activities. Prosthetic feet with high energy return and low mass will perform better during treadmill running. Non-amputee controls will demonstrate superior performance in all outcomes in both field and laboratory environments compared to amputee subjects. Relevance: This study has the potential to quantify differences between highly mobile amputees and non-amputees. Additionally, it will provide objective measures of how different prostheses may enhance mobility of soldiers with amputations. The study will compare laboratory and field measures to indicate which conditions increase efficiency of prostheses during rapidly changing mobility demands. This has the potential to permit retention of already trained soldiers.

Official Title
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Metabolic and Biomechanical Measures of Gait Efficiency of Three Multi-Axial, Vertical Shock and Energy Storing-Return Prosthetic Feet During Simple & Complex Mobility Activities

Conditions
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Amputation

Intervention / Treatment
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* Device: Ossur Variflex prosthetic foot
* Device: Ossur Ceterus prosthetic foot
* Device: Endolite Elite Blade prosthetic foot


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria (Amputees): Unilateral transtibial amputee ambulating on a K4 prosthesis for >1yr K4 functional level Currently active duty military or other uniformed service (e.g. police), recently separated Veteran, or strong high-performance athletic history as an amputee (e.g. ranked triathlete, paralympian, etc.) Schedule availability and willingness to comply with study protocols Aged < 45 years Medical clearance, within the last 6 months, for participation in vigorous physical activities Inclusion Criteria (Non-amputees) Currently active duty military, ROTC, or other uniformed service (e.g. police) or recently separated Veteran, or highly accomplished recreational athlete (e.g. marathoner) Schedule availability and willingness to comply with study protocols Aged < 45 years Medical clearance, within the last 6 months, for participation in vigorous physical activities

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Prosthetic foot 1 (Ossur Variflex)<br>This arm included unilateral transtibial amputees who who were assessed while using prosthetic foot 1 (Ossur Variflex). | Device: Ossur Variflex prosthetic foot<br>* Lightweight energy-storing prosthetic foot<br>|
| Active Comparator: Prosthetic foot 2 (Ossur Ceterus)<br>This arm included unilateral transtibial amputees who who were assessed while using prosthetic foot 2 (Ossur Ceterus). | Device: Ossur Ceterus prosthetic foot<br>* Shock-absorbing prosthetic foot<br>|
| Active Comparator: Prosthetic foot 3 (Endolite Elite Blade)<br>This arm included unilateral transtibial amputees who who were assessed while using prosthetic foot 3 (Endolite Elite Blade). | Device: Endolite Elite Blade prosthetic foot<br>* Multi-axial prosthetic foot<br>|
| No Intervention: Non-amputee controls<br>This was an observational arm including non-amputees who were assessed as non-impaired control subjects. There are no interventions in this observational arm of the study. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Obstacle Course Completion Time | Laser timing lights were used to measure time necessary to complete a 17 task obstacle course. Participants trigger the laser timing lights when they run past them and the times are recorded in a laptop computer. Laser lights are set up in pairs at the beginning and end of the obstacle course. | 21 days total (7days per prosthetic foot condition) | 
| Bioenergetics Between Feet Components 21 Days After Fitting Prostheses | Measures of energy expenditure while walking on a treadmill were measured. Expired gas (e.g. oxygen and carbon dioxide) are breathed into a face mask worn by participants. The mask contains sensors to detect the levels of the respective gas. Oxygen uptake is correlated with effort to ambulate and therefore, the more oxygen consumed during walking, the more difficult the bout of activity. Thus, if one prosthetic foot requires the consumption of more or less oxygen than other feet, then this is an indicator of the relative difficulty of walking with that particular foot condition. | 21 days total (7days per prosthetic foot condition) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Amputee, Transtibial, Military, Gait, Rehabilitation