Transtibial Amputation
Conditions
Brief summary
The goal of this study is to evaluate endurance, walking performance, mobility, and perceived exertion of transtibial prosthesis users (i.e., study participants) walking with a conventional energy storing prosthetic foot (ESF) and a novel modified running-specific prosthesis (mRSF). A randomized cross-over study will be conducted to determine if the mRSF provides superior performance to the ESF, which is commonly prescribed to most active individuals with lower limb amputation.
Detailed description
Amputation of a limb is a life-altering event with profound physical, psychological, and social implications. To address their functional, vocational, and recreational needs, people with lower limb amputation (LLA) are often provided with a prosthesis or artificial leg. While use of a prosthesis can allow an individual to achieve a basic level of functional mobility, absence of an anatomical foot and ankle still impairs their physical performance. As a result, people with LLA regularly exhibit decreased walking speeds, diminished endurance, and restricted ability to participate in desired life situations. Over the past three decades, increasingly sophisticated prosthetic foot designs have been developed by the prosthetics industry to replace amputated structures in the leg. Contemporary, energy storing feet (ESF) employ advanced materials and unique geometric designs to improve walking performance and endurance of their users. Although prosthetic limbs with ESF allow people with LLA the potential to return to an active lifestyle, even the most advanced ESF do not significantly reduce the increased energy demands required for walking when compared to conventional prosthetic feet. Commercially-available running-specific feet (RSF) like the Össur Cheetah (Össur, Reykjavik, Iceland) allow people with LLA to participate in athletic activities and sporting events. RSF provide significantly enhanced performance, compared to traditional ESF, by extending the length and increasing the stiffness of the prosthetic keel (forefoot). RSF also do not include a heel, as they are used only for running activities. Although transtibial runners with RSF exhibit endurance levels similar to non-amputees, the RSF design does not allow the biomechanical movements or provide the stability needed to use the foot for walking (over level or uneven terrain). A novel modified running-specific foot (mRSF) has been developed to integrate the performance of a RSF with the utility of an ESF. The mRSF combines the running keel (forefoot) of a RSF with the walking heel of a ESF. The mRSF can then be used for walking, running, and other routine daily activities. Preliminary feedback on the mRSF suggests that users experience improved overall function and high satisfaction with the device. However, empirical evidence is needed to support prescription of this prosthetic foot at other clinical facilities. The goal of this study is therefore to evaluate endurance, walking performance, mobility, and perceived exertion of transtibial prosthesis users (i.e., study participants) walking with a conventional ESF and the mRSF. Results will be compared to determine if the mRSF provides superior performance to the ESF, which is commonly prescribed to most active individuals with LLA.
Interventions
DEVICEEnergy storing foot (ESF)
A commercially-available energy storing prosthetic foot
DEVICEModified running specific foot (mRSF)
A running specific prosthetic foot customized for both running and walking activities
Sponsors
University of Washington
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* unilateral or bilateral, transtibial (below-knee) amputation from non-dysvascular causes * Medicare functional classification level (K-level) 3 or higher (unlimited community ambulatory) * prosthetic user for \> 1 year * scheduled to receive a mRSF prosthesis * able and willing to participate in the study protocol (e.g., treadmill walking, overground walking, respond to survey questions, able to read and write English)
Exclusion criteria
* contralateral lower or upper limb involvement * any health condition that would limit participation in the study procedures (e.g., skin breakdown, heart disease)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Step Time, Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Step time was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step time is reported for both the prosthetic and sound (intact) limbs. |
| Six-minute Walk Test (6MWT), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Participants were asked to walk as far as possible in 6 minutes. Participants walked around cones placed 30m apart in a level hallway. Total distance (in meters) walked in 6 minutes was recorded. |
| Borg Rating of Perceived Exertion (CR100), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Participants were asked to self-report their level of perceived exertion after completing the 6MWT. Participants were shown the Borg CR100 rating scale and asked to identify their level of exertion on a scale ranging from 0 to 120. Higher scores mean greater exertion. |
| Borg Rating of Perceived Exertion (CR100), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Participants were asked to self-report their level of perceived exertion after completing the 6MWT. Participants were shown the Borg CR100 rating scale and asked to identify their level of exertion on a scale ranging from 0 to 120. Higher scores mean greater exertion. |
| Walking Speed, Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Walking speed (m/s) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). |
| Walking Speed, Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Walking speed (m/s) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). |
| Step Width, Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Step width was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). |
| Step Width, Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Step width was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). |
| Step Length, Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Step length (cm) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step length is reported for both the prosthetic and sound (intact) limbs. |
| Step Length, Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Step length (cm) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step length is reported for both the prosthetic and sound (intact) limbs. |
| Step Time, Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Step time was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step time is reported for both the prosthetic and sound (intact) limbs. |
| Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Breath-by-Breath VO2 was collected as participants walked on a treadmill at self selected fast, normal, and slow speeds. Participants walked for 6 minutes at each speed (and in each experimental condition). VO2 was normalized energy expenditure to each participant's biological mass (i.e., body mass without prosthesis) Normalized VO2 data were averaged to produce 30-s values for minutes 3-6 of each trial. These 30-s values were used in for the described analyses. Both gross and net VO2 were examined, but produced similar results, so only gross VO2 results are reported. |
| Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Breath-by-Breath VO2 was collected as participants walked on a treadmill at self selected fast, normal, and slow speeds. Participants walked for 6 minutes at each speed (and in each experimental condition). VO2 was normalized energy expenditure to each participant's biological mass (i.e., body mass without prosthesis) Normalized VO2 data were averaged to produce 30-s values for minutes 3-6 of each trial. These 30-s values were used in for the described analyses. Both gross and net VO2 were examined, but produced similar results, so only gross VO2 results are reported. |
| Six-minute Walk Test (6MWT), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | Participants were asked to walk as far as possible in 6 minutes. Participants walked around cones placed 30m apart in a level hallway. Total distance (in meters) walked in 6 minutes was recorded. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Daily Step Activity, Participants With Bilateral Amputation | Participants' step count data from the 2 weeks prior to in-person testing. | Daily step activity (steps / day) were measured over the 2-week period prior to assessment using a Orthocare Innovations Stepwatch 3 activity monitor. |
| Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The PLUS-M is a self-report instrument designed to evaluate respondent's prosthetic mobility. It is scored using a standardized T-score centered on a national sample of unilateral lower limb prosthesis users (mean = 50, standard deviation = 10). Participants were administered the PLUS-M computerized adaptive test and 12-item form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater mobility. |
| Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The PLUS-M is a self-report instrument designed to evaluate respondent's prosthetic mobility. It is scored using a standardized T-score centered on a national sample of unilateral lower limb prosthesis users (mean = 50, standard deviation = 10). Participants were administered the PLUS-M computerized adaptive test and 12-item form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater mobility. |
| Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The PROMIS-Fatigue is a self-report instrument designed to evaluate respondent's symptoms and effects of fatigue. It is scored using a standardized T-score centered on the US general population (mean = 50, standard deviation = 10). Participants were administered the computerized adaptive test and a 12-item short form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater fatigue. |
| Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The PROMIS-Fatigue is a self-report instrument designed to evaluate respondent's symptoms and effects of fatigue. It is scored using a standardized T-score centered on the US general population (mean = 50, standard deviation = 10). Participants were administered the computerized adaptive test and a 12-item short form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater fatigue. |
| Activities-Specific Balance Confidence Scale (ABC), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The ABC is a self-report instrument designed to evaluate respondent's confidence in performing normal daily activities. It is scored from 0 to 4. Participants were administered an electronic version of the ABC on an iPad tablet. Scores range from 0 to 4. Higher scores indicate greater balance confidence. |
| Activities-Specific Balance Confidence Scale (ABC), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The ABC is a self-report instrument designed to evaluate respondent's confidence in performing normal daily activities. It is scored from 0 to 4. Participants were administered an electronic version of the ABC on an iPad tablet. Scores range from 0 to 4. Higher scores indicate greater balance confidence. |
| Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The TAPES-R is a self-report instrument designed to evaluate respondent's activity restrictions and satisfaction with a prosthesis. The TAPES-R has three subscales (activity restrictions \[TAPES-AR\], functional satisfaction \[TAPES-FUN\], and aesthetic satisfaction \[TAPES-AES\], each scored from 0 to 2. Higher scores indicate more activity restrictions (TAPES-AR) or greater satisfaction (TAPES-FUN and TAPES-AES). Participants were administered an electronic version of the TAPES-R on an iPad tablet. |
| Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | Participants were tested after using each foot in their prosthesis for 1 month. | The TAPES-R is a self-report instrument designed to evaluate respondent's activity restrictions and satisfaction with a prosthesis. The TAPES-R has three subscales (activity restrictions \[TAPES-AR\], functional satisfaction \[TAPES-FUN\], and aesthetic satisfaction \[TAPES-AES\], each scored from 0 to 2. Higher scores indicate more activity restrictions (TAPES-AR) or greater satisfaction (TAPES-FUN and TAPES-AES). Participants were administered an electronic version of the TAPES-R on an iPad tablet. |
| Daily Step Activity, Participants With Unilateral Amputation | Participants' step count data from the 2 weeks prior to in-person testing. | Daily step activity (steps / day) were measured over the 2-week period prior to assessment using a Orthocare Innovations Stepwatch 3 activity monitor. |
Countries
United States
Participant flow
Recruitment details
39 participants were screened for eligibility between May 15, 2015 and 09/26/2017 at a research laboratory in Seattle, WA.
Pre-assignment details
39 participants were randomized. 3 participants did not meet the eligibility criteria. 36 participants were enrolled.
Participants by arm
| Arm | Count |
|---|---|
| mRSF-ESF Study participants in Arm 1 will first receive the Modified running specific foot (mRSF) and then the Energy storing foot (ESF). Outcomes will be assessed (in each condition) after 1 month of use. Order of interventions will be randomly assigned.
Energy storing foot (ESF): A commercially-available energy storing prosthetic foot
Modified running specific foot (mRSF): A running specific prosthetic foot customized for both running and walking activities | 16 |
| ESF-mRSF Study participants in Arm 2 will first receive the Energy storing foot (ESF) and then the Modified running specific foot (mRSF). Outcomes will be assessed (in each condition) after 1 month of use. Order of interventions will be randomly assigned.
Energy storing foot (ESF): A commercially-available energy storing prosthetic foot
Modified running specific foot (mRSF): A running specific prosthetic foot customized for both running and walking activities | 20 |
| Total | 36 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Second Intervention | Lost to Follow-up | 1 | 0 |
Baseline characteristics
| Characteristic | mRSF-ESF | Total | ESF-mRSF |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 1 Participants | 1 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 15 Participants | 35 Participants | 20 Participants |
| Age, Continuous | 43.9 years STANDARD_DEVIATION 10.6 | 44.0 years STANDARD_DEVIATION 11 | 44.0 years STANDARD_DEVIATION 11.6 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 1 Participants | 2 Participants | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 15 Participants | 34 Participants | 19 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Height | 180.9 centimeters STANDARD_DEVIATION 8.6 | 178.5 centimeters STANDARD_DEVIATION 9.7 | 176.6 centimeters STANDARD_DEVIATION 10.3 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 2 Participants | 1 Participants |
| Race (NIH/OMB) White | 15 Participants | 31 Participants | 16 Participants |
| Region of Enrollment United States | 16 participants | 36 participants | 20 participants |
| Sex: Female, Male Female | 1 Participants | 7 Participants | 6 Participants |
| Sex: Female, Male Male | 15 Participants | 29 Participants | 14 Participants |
| Weight | 82.5 kilograms STANDARD_DEVIATION 12.7 | 84.4 kilograms STANDARD_DEVIATION 18.5 | 85.9 kilograms STANDARD_DEVIATION 22.3 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 36 | 0 / 36 |
| other Total, other adverse events | 0 / 36 | 0 / 36 |
| serious Total, serious adverse events | 0 / 36 | 0 / 36 |
Outcome results
Primary
Borg Rating of Perceived Exertion (CR100), Participants With Bilateral Amputation
Participants were asked to self-report their level of perceived exertion after completing the 6MWT. Participants were shown the Borg CR100 rating scale and asked to identify their level of exertion on a scale ranging from 0 to 120. Higher scores mean greater exertion.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Borg Rating of Perceived Exertion (CR100), Participants With Bilateral Amputation | 30.4 units on a scale | Standard Deviation 21.7 |
| ESF (Unilateral) | Borg Rating of Perceived Exertion (CR100), Participants With Bilateral Amputation | 35.6 units on a scale | Standard Deviation 19.2 |
Primary
Borg Rating of Perceived Exertion (CR100), Participants With Unilateral Amputation
Participants were asked to self-report their level of perceived exertion after completing the 6MWT. Participants were shown the Borg CR100 rating scale and asked to identify their level of exertion on a scale ranging from 0 to 120. Higher scores mean greater exertion.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Borg Rating of Perceived Exertion (CR100), Participants With Unilateral Amputation | 36.4 units on a scale | Standard Deviation 31.4 |
| ESF (Unilateral) | Borg Rating of Perceived Exertion (CR100), Participants With Unilateral Amputation | 47.3 units on a scale | Standard Deviation 28 |
p-value: 0.05t-test, 2 sided
Primary
Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation
Breath-by-Breath VO2 was collected as participants walked on a treadmill at self selected fast, normal, and slow speeds. Participants walked for 6 minutes at each speed (and in each experimental condition). VO2 was normalized energy expenditure to each participant's biological mass (i.e., body mass without prosthesis) Normalized VO2 data were averaged to produce 30-s values for minutes 3-6 of each trial. These 30-s values were used in for the described analyses. Both gross and net VO2 were examined, but produced similar results, so only gross VO2 results are reported.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | VO2 - slow walking speed | 779.6 ml/min | Standard Deviation 299.2 |
| mRSF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | VO2 - comfortable walking speed | 889.9 ml/min | Standard Deviation 300.8 |
| mRSF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | VO2 - fast walking speed | 1081.9 ml/min | Standard Deviation 319 |
| ESF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | VO2 - slow walking speed | 867.3 ml/min | Standard Deviation 397.7 |
| ESF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | VO2 - comfortable walking speed | 985.0 ml/min | Standard Deviation 413.4 |
| ESF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation | VO2 - fast walking speed | 1162.8 ml/min | Standard Deviation 439.3 |
Primary
Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation
Breath-by-Breath VO2 was collected as participants walked on a treadmill at self selected fast, normal, and slow speeds. Participants walked for 6 minutes at each speed (and in each experimental condition). VO2 was normalized energy expenditure to each participant's biological mass (i.e., body mass without prosthesis) Normalized VO2 data were averaged to produce 30-s values for minutes 3-6 of each trial. These 30-s values were used in for the described analyses. Both gross and net VO2 were examined, but produced similar results, so only gross VO2 results are reported.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | VO2 - slow walking speed | 1041.1 ml/min | Standard Deviation 246.1 |
| mRSF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | VO2 - comfortable walking speed | 1210.9 ml/min | Standard Deviation 280.9 |
| mRSF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | VO2 - fast walking speed | 1509.6 ml/min | Standard Deviation 398.8 |
| ESF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | VO2 - slow walking speed | 1077.4 ml/min | Standard Deviation 245.2 |
| ESF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | VO2 - comfortable walking speed | 1253.5 ml/min | Standard Deviation 276.3 |
| ESF (Unilateral) | Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation | VO2 - fast walking speed | 1565.1 ml/min | Standard Deviation 376.4 |
Comparison: Analysis of VO2 at slow walking speedp-value: 0.18Multivariate regression
Comparison: Analysis of VO2 at comfortable walking speedp-value: 0.21Multivariate regression
Comparison: Analysis of VO2 at fast walking speedp-value: 0.16Multivariate regression
Primary
Six-minute Walk Test (6MWT), Participants With Bilateral Amputation
Participants were asked to walk as far as possible in 6 minutes. Participants walked around cones placed 30m apart in a level hallway. Total distance (in meters) walked in 6 minutes was recorded.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Six-minute Walk Test (6MWT), Participants With Bilateral Amputation | 441.1 meters | Standard Deviation 72.7 |
| ESF (Unilateral) | Six-minute Walk Test (6MWT), Participants With Bilateral Amputation | 448.9 meters | Standard Deviation 77.5 |
Primary
Six-minute Walk Test (6MWT), Participants With Unilateral Amputation
Participants were asked to walk as far as possible in 6 minutes. Participants walked around cones placed 30m apart in a level hallway. Total distance (in meters) walked in 6 minutes was recorded.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Six-minute Walk Test (6MWT), Participants With Unilateral Amputation | 543.3 meters | Standard Deviation 92.6 |
| ESF (Unilateral) | Six-minute Walk Test (6MWT), Participants With Unilateral Amputation | 537.1 meters | Standard Deviation 100.8 |
p-value: 0.29t-test, 2 sided
Primary
Step Length, Participants With Bilateral Amputation
Step length (cm) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step length is reported for both the prosthetic and sound (intact) limbs.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Step Length, Participants With Bilateral Amputation | Left side | 0.69 centimeters | Standard Deviation 0.08 |
| mRSF (Unilateral) | Step Length, Participants With Bilateral Amputation | Right side | 0.69 centimeters | Standard Deviation 0.11 |
| ESF (Unilateral) | Step Length, Participants With Bilateral Amputation | Left side | 0.68 centimeters | Standard Deviation 0.13 |
| ESF (Unilateral) | Step Length, Participants With Bilateral Amputation | Right side | 0.69 centimeters | Standard Deviation 0.12 |
Primary
Step Length, Participants With Unilateral Amputation
Step length (cm) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step length is reported for both the prosthetic and sound (intact) limbs.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Step Length, Participants With Unilateral Amputation | Prosthetic side | 78.8 centimeters | Standard Deviation 9.2 |
| mRSF (Unilateral) | Step Length, Participants With Unilateral Amputation | Sound side | 79.5 centimeters | Standard Deviation 10.2 |
| ESF (Unilateral) | Step Length, Participants With Unilateral Amputation | Prosthetic side | 79.4 centimeters | Standard Deviation 9.4 |
| ESF (Unilateral) | Step Length, Participants With Unilateral Amputation | Sound side | 76.5 centimeters | Standard Deviation 9.8 |
Comparison: Prosthetic side step length resultsp-value: 0.14t-test, 2 sided
Comparison: Sound side step length resultsp-value: <0.001t-test, 2 sided
Primary
Step Time, Participants With Bilateral Amputation
Step time was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step time is reported for both the prosthetic and sound (intact) limbs.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Step Time, Participants With Bilateral Amputation | Right side | 0.53 seconds | Standard Deviation 0.05 |
| mRSF (Unilateral) | Step Time, Participants With Bilateral Amputation | Left side | 0.51 seconds | Standard Deviation 0.04 |
| ESF (Unilateral) | Step Time, Participants With Bilateral Amputation | Right side | 0.52 seconds | Standard Deviation 0.04 |
| ESF (Unilateral) | Step Time, Participants With Bilateral Amputation | Left side | 0.51 seconds | Standard Deviation 0.03 |
Primary
Step Time, Participants With Unilateral Amputation
Step time was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT). Step time is reported for both the prosthetic and sound (intact) limbs.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Step Time, Participants With Unilateral Amputation | Prosthetic side | 0.49 seconds | Standard Deviation 0.05 |
| mRSF (Unilateral) | Step Time, Participants With Unilateral Amputation | Sound side | 0.50 seconds | Standard Deviation 0.05 |
| ESF (Unilateral) | Step Time, Participants With Unilateral Amputation | Prosthetic side | 0.49 seconds | Standard Deviation 0.05 |
| ESF (Unilateral) | Step Time, Participants With Unilateral Amputation | Sound side | 0.50 seconds | Standard Deviation 0.05 |
Comparison: Prosthetic side step time resultsp-value: 0.61t-test, 2 sided
Comparison: Sound side step time resultsp-value: 0.4t-test, 2 sided
Primary
Step Width, Participants With Bilateral Amputation
Step width was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT).
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Step Width, Participants With Bilateral Amputation | 16.9 centimeters | Standard Deviation 5.4 |
| ESF (Unilateral) | Step Width, Participants With Bilateral Amputation | 16.7 centimeters | Standard Deviation 5 |
Primary
Step Width, Participants With Unilateral Amputation
Step width was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT).
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Step Width, Participants With Unilateral Amputation | 13.7 centimeters | Standard Deviation 3.8 |
| ESF (Unilateral) | Step Width, Participants With Unilateral Amputation | 13.7 centimeters | Standard Deviation 3.5 |
p-value: 0.86t-test, 2 sided
Primary
Walking Speed, Participants With Bilateral Amputation
Walking speed (m/s) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT).
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Walking Speed, Participants With Bilateral Amputation | 1.35 meters / second | Standard Deviation 0.23 |
| ESF (Unilateral) | Walking Speed, Participants With Bilateral Amputation | 1.35 meters / second | Standard Deviation 0.28 |
Primary
Walking Speed, Participants With Unilateral Amputation
Walking speed (m/s) was assessed with a 16-foot CIR GAITRite instrumented walkway while participants performed the 6-minute walk test (6MWT).
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Walking Speed, Participants With Unilateral Amputation | 1.62 meters / second | Standard Deviation 0.29 |
| ESF (Unilateral) | Walking Speed, Participants With Unilateral Amputation | 1.60 meters / second | Standard Deviation 0.31 |
p-value: 0.25t-test, 2 sided
Secondary
Activities-Specific Balance Confidence Scale (ABC), Participants With Bilateral Amputation
The ABC is a self-report instrument designed to evaluate respondent's confidence in performing normal daily activities. It is scored from 0 to 4. Participants were administered an electronic version of the ABC on an iPad tablet. Scores range from 0 to 4. Higher scores indicate greater balance confidence.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Activities-Specific Balance Confidence Scale (ABC), Participants With Bilateral Amputation | 3.4 score on a scale | Standard Deviation 0.3 |
| ESF (Unilateral) | Activities-Specific Balance Confidence Scale (ABC), Participants With Bilateral Amputation | 3.0 score on a scale | Standard Deviation 0.5 |
Secondary
Activities-Specific Balance Confidence Scale (ABC), Participants With Unilateral Amputation
The ABC is a self-report instrument designed to evaluate respondent's confidence in performing normal daily activities. It is scored from 0 to 4. Participants were administered an electronic version of the ABC on an iPad tablet. Scores range from 0 to 4. Higher scores indicate greater balance confidence.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Activities-Specific Balance Confidence Scale (ABC), Participants With Unilateral Amputation | 3.5 score on a scale | Standard Deviation 0.4 |
| ESF (Unilateral) | Activities-Specific Balance Confidence Scale (ABC), Participants With Unilateral Amputation | 3.2 score on a scale | Standard Deviation 0.7 |
p-value: 0.005t-test, 2 sided
Secondary
Daily Step Activity, Participants With Bilateral Amputation
Daily step activity (steps / day) were measured over the 2-week period prior to assessment using a Orthocare Innovations Stepwatch 3 activity monitor.
Time frame: Participants' step count data from the 2 weeks prior to in-person testing.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Daily Step Activity, Participants With Bilateral Amputation | 2464 steps per day | Standard Deviation 455 |
| ESF (Unilateral) | Daily Step Activity, Participants With Bilateral Amputation | 3007 steps per day | Standard Deviation 617 |
Secondary
Daily Step Activity, Participants With Unilateral Amputation
Daily step activity (steps / day) were measured over the 2-week period prior to assessment using a Orthocare Innovations Stepwatch 3 activity monitor.
Time frame: Participants' step count data from the 2 weeks prior to in-person testing.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Daily Step Activity, Participants With Unilateral Amputation | 4109 steps per day | Standard Deviation 1517 |
| ESF (Unilateral) | Daily Step Activity, Participants With Unilateral Amputation | 4307 steps per day | Standard Deviation 1750 |
p-value: 0.14t-test, 2 sided
Secondary
Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Bilateral Amputation
The PROMIS-Fatigue is a self-report instrument designed to evaluate respondent's symptoms and effects of fatigue. It is scored using a standardized T-score centered on the US general population (mean = 50, standard deviation = 10). Participants were administered the computerized adaptive test and a 12-item short form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater fatigue.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Bilateral Amputation | 42.1 T-score | Standard Deviation 8.9 |
| ESF (Unilateral) | Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Bilateral Amputation | 47.7 T-score | Standard Deviation 6.2 |
Secondary
Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Unilateral Amputation
The PROMIS-Fatigue is a self-report instrument designed to evaluate respondent's symptoms and effects of fatigue. It is scored using a standardized T-score centered on the US general population (mean = 50, standard deviation = 10). Participants were administered the computerized adaptive test and a 12-item short form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater fatigue.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Unilateral Amputation | 45.4 T-score | Standard Deviation 7.5 |
| ESF (Unilateral) | Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Unilateral Amputation | 49.1 T-score | Standard Deviation 7.4 |
p-value: 0.001t-test, 2 sided
Secondary
Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Bilateral Amputation
The PLUS-M is a self-report instrument designed to evaluate respondent's prosthetic mobility. It is scored using a standardized T-score centered on a national sample of unilateral lower limb prosthesis users (mean = 50, standard deviation = 10). Participants were administered the PLUS-M computerized adaptive test and 12-item form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater mobility.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Bilateral Amputation | 59.3 T-score | Standard Deviation 3.8 |
| ESF (Unilateral) | Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Bilateral Amputation | 54.8 T-score | Standard Deviation 6.2 |
Secondary
Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Unilateral Amputation
The PLUS-M is a self-report instrument designed to evaluate respondent's prosthetic mobility. It is scored using a standardized T-score centered on a national sample of unilateral lower limb prosthesis users (mean = 50, standard deviation = 10). Participants were administered the PLUS-M computerized adaptive test and 12-item form on an iPad tablet. The most precise score (i.e., score with the lowest error) was used for analysis. Absolute score range from 0 to 100. Higher T-scores indicate greater mobility.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| mRSF (Unilateral) | Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Unilateral Amputation | 64.2 T-score | Standard Deviation 7.7 |
| ESF (Unilateral) | Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Unilateral Amputation | 59.3 T-score | Standard Deviation 7.5 |
p-value: 0.001t-test, 2 sided
Secondary
Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation
The TAPES-R is a self-report instrument designed to evaluate respondent's activity restrictions and satisfaction with a prosthesis. The TAPES-R has three subscales (activity restrictions \[TAPES-AR\], functional satisfaction \[TAPES-FUN\], and aesthetic satisfaction \[TAPES-AES\], each scored from 0 to 2. Higher scores indicate more activity restrictions (TAPES-AR) or greater satisfaction (TAPES-FUN and TAPES-AES). Participants were administered an electronic version of the TAPES-R on an iPad tablet.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from participants with bilateral amputation.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | TAPES-AR | 0.7 score on a scale | Standard Deviation 0.2 |
| mRSF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | TAPES-FUN | 1.8 score on a scale | Standard Deviation 0.4 |
| mRSF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | TAPES-AES | 1.8 score on a scale | Standard Deviation 0.3 |
| ESF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | TAPES-AR | 0.9 score on a scale | Standard Deviation 0.2 |
| ESF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | TAPES-FUN | 1.1 score on a scale | Standard Deviation 0.2 |
| ESF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation | TAPES-AES | 0.9 score on a scale | Standard Deviation 0.5 |
Secondary
Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation
The TAPES-R is a self-report instrument designed to evaluate respondent's activity restrictions and satisfaction with a prosthesis. The TAPES-R has three subscales (activity restrictions \[TAPES-AR\], functional satisfaction \[TAPES-FUN\], and aesthetic satisfaction \[TAPES-AES\], each scored from 0 to 2. Higher scores indicate more activity restrictions (TAPES-AR) or greater satisfaction (TAPES-FUN and TAPES-AES). Participants were administered an electronic version of the TAPES-R on an iPad tablet.
Time frame: Participants were tested after using each foot in their prosthesis for 1 month.
Population: Data are from 27 participants with unilateral amputation. Data from 1 participant who did not complete the protocol and 3 participants who experienced serious life events unrelated to the study that disproportionately affected one phase of the study were not analyzed.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| mRSF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | TAPES-AR | 0.4 score on a scale | Standard Deviation 0.3 |
| mRSF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | TAPES-FUN | 1.8 score on a scale | Standard Deviation 0.4 |
| mRSF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | TAPES-AES | 1.5 score on a scale | Standard Deviation 0.5 |
| ESF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | TAPES-AR | 0.6 score on a scale | Standard Deviation 0.4 |
| ESF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | TAPES-FUN | 1.3 score on a scale | Standard Deviation 0.5 |
| ESF (Unilateral) | Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation | TAPES-AES | 1.5 score on a scale | Standard Deviation 0.5 |
Comparison: TAPES-AR resultsp-value: 0.002t-test, 2 sided
Comparison: TAPES-FUN resultsp-value: <0.001t-test, 2 sided
Comparison: TAPES-AES resultsp-value: 0.85t-test, 2 sided