CompletedNCT04239222Updated Sep 23, 2024Results posted

Feasibility Study to Evaluate a New Energy Storage and Return Prosthetic Foot

An interventional study of Revo-M and Taleo in Lower Limb Amputation Below Knee (Injury), Lower Limb Amputation Above Knee (Injury) and Lower Limb Amputation Knee, sponsored by Otto Bock Healthcare Products GmbH. Completed at 4 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2024-09-23.

Sponsored by Otto Bock Healthcare Products GmbH · Not applicable, Interventional, and Treatment

Phase: Not applicable
Study type: Interventional
Enrollment: 27
Allocation: Randomized
Ages: 18 Years and older
Sex: All

Study summary

A prospective, interventional, multicenter pilot study to characterize differences in performance and patient reported outcomes between the Taleo, Proflex XC, and the new Revo prosthetic foot.

Read the detailed description

The purpose of the Revo-M Study is to characterize differences in performance and patient reported outcomes between the Revo investigational prosthetic foot and a comparative prosthetic foot (Taleo or Proflex XC) when compared to the control foot which is the subject's currently used energy storage and return (ESR) prosthetic foot. The data obtained from this study may also serve to determine the long-term performance of Revo.

Conditions studied

Lower Limb Amputation Below Knee (Injury)
Lower Limb Amputation Above Knee (Injury)
Lower Limb Amputation Knee

Browse trials for

Wounds and Injuries 2,217

Keywords

Prosthetic foot, lower limb amputation

In context

Wounds and Injuries

2,217 studies on the registry are indexed under Wounds and Injuries; 441 are open to participants now.

This study's enrollment of 27 is below the median of 70 across 1,424 interventional studies indexed under Wounds and Injuries.

Browse Wounds and Injuries studies →

Lead sponsor

Otto Bock Healthcare Products GmbH is the lead sponsor of 10 studies on the registry; 3 are open to participants now.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

Person is 18 years or older.
Currently uses an energy storage and return foot.
Person has been a unilateral transfemoral (TF), or transtibial (TT) amputee using a prosthesis for at least 1 year.
For TF amputees, the person must be wearing an Ottobock Microprocessor-controlled Knee (MPK) with a compatible prosthetic foot
Person weighs ≤ 275 lbs (125 kg) size 26-27cm or ≤ 220 lbs (100 kg) size 24-25cm
Person is a K3 ambulator based on Medicare Functional Classification Level (MFCL).
Prosthetic foot size is 24 to 27 centimeters.
Socket Comfort Score of at least 7
Ability to read and understand English
A person is able and willing to give consent

Exclusion criteria

Exclusion Criteria:

Current prosthetic foot is too old or worn out as assessed by the CPO.
TT subject with currently fit with a Proflex XC or TF subject currently fit with a Taleo.
Patient is pregnant or planning to become pregnant.
Person who has a life-threatening medical condition (i.e. terminal cancer, severe heart disease).
Person has conditions that would prevent participation and pose increased risk (e.g. unstable cardiovascular conditions that preclude physical activity such as walking, problems with vestibular system, etc.).
Ulceration or skin breakdown of the residual limb.
Person currently has residual limb issues that significantly reduce their ability to load the prosthesis.

Study design

Phase: Not applicable
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Crossover assignment
Masking: None (open label)
Enrollment: 27 participants (actual)

Study arms

Experimental
Revo-M to Proflex XC
Transtibial amputees randomized to start with Revo-M and cross over to Proflex XC
Device: Revo-M · Device: Proflex XC
Experimental
Proflex XC to Revo-M
Transtibial amputees randomized to start with Proflex XC and cross over to Revo-M
Device: Revo-M · Device: Proflex XC
Experimental
Revo-M to Taleo
Transfemoral amputees randomized to start with Revo-M and cross over to Taleo
Device: Revo-M · Device: Taleo
Experimental
Taleo to Revo-M
Transfemoral amputees randomized to start with Taleo and cross over to Revo-M
Device: Revo-M · Device: Taleo

Interventions

DeviceRevo-M
Investigational energy storage and return prosthetic foot with using novel elastic elements.
DeviceTaleo
Commercially available carbon-fiber energy storage and return foot used as comparative foot for transfemoral amputee subjects
DeviceProflex XC
Commercially available carbon-fiber energy storage and return foot used as comparative foot for transtibial amputee subjects

What researchers measure

Primary outcomes

Patient-perceived Mobility (PLUS-M)™
Perception of mobility as measured by the Prosthetic Limb Users Survey of Mobility (PLUS-M) 12-item short form. The PLUS-M questionnaire provides a T-score that ranges from 21.8 to 71.4. Higher PLUS-M scores correspond with greater mobility. The T-score has a mean of 50 and a standard deviation (SD) of 10. A PLUS-M T-score of 50 represents the mean mobility reported by the development sample. A T-score greater than 57 indicates that the mobility is above the 75th percentile.
Time frame: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale)
Activity restrictions as measured by the Revised Trinity Amputation and Prosthesis Experience Scales Activity Restrictions subscale (TAPES-AR). The TAPES-AR subscale has 10 items on a three-point scale and the average score ranges from 0 to 2. A higher score indicates greater activity restriction.
Time frame: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot

Secondary outcomes

Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test
The percentage of subjects showing an improvement compared to baseline walking endurance as measured by the distance walked in the six minute walk test OR a decrease in the rating of perceived exertion (RPE) as measured by Borg CR100 while wearing the Revo-M. A clinically-significant improvement in the 6MWT is defined as a change in distance of greater than 45 meters. A clinically-significant improvement in the RPE is defined as a change greater than 10 points. The Borg CR100 scale has a minimum of 0 and a maximum of 100. Greater scores indicate higher perceived exertion.
Time frame: 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Patient Perceived Balance Confidence (ABC)
Perception of balance confidence as measured by the extended Activities-specific Balance Confidence (ABC) Scale. The questionnaire provides a score that ranges from 0 to 100%. Higher scores indicate greater balance confidence.
Time frame: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Functional Satisfaction With Prosthesis (TAPES-FUN)
To characterize the level of functional satisfaction as measured by the TAPES Functional Satisfaction (TAPES-FUN) subscale while wearing a given prosthetic foot. There are 5 items scaled from 1 to 5. The subscale provides a total score that ranges from 5 to 25. Higher scores indicate greater functional satisfaction.
Time frame: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot

Results

Posted Sep 23, 2024

Limitations and caveats

A small overall sample. One subject could not tolerate the Taleo foot for any amount of time and so was not assessed on the Taleo.

Participant flow

Baseline

Participant flow — Baseline
Milestone	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M
Started	6	8	4	8
Completed	6	8	3	7
Not completed	0	0	1	1
Withdrew: Withdrawal by subject	0	0	1	1

First Foot Assignment

Participant flow — First Foot Assignment
Milestone	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M
Started	6	8	3	7
Completed	6	8	2	7
Not completed	0	0	1	0
Withdrew: Withdrawal by subject	0	0	1	0

Crossover to Alternate Foot Assignment

Participant flow — Crossover to Alternate Foot Assignment
Milestone	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M
Started	6	8	2	7
Completed	6	8	1	7
Not completed	0	0	1	0
Withdrew: Protocol violation	0	0	1	0

Return to Baseline Foot

Participant flow — Return to Baseline Foot
Milestone	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M
Started	6	8	2	7
Completed	6	8	2	7
Not completed	0	0	0	0

Outcome measures

PrimaryPatient-perceived Mobility (PLUS-M)™

Perception of mobility as measured by the Prosthetic Limb Users Survey of Mobility (PLUS-M) 12-item short form. The PLUS-M questionnaire provides a T-score that ranges from 21.8 to 71.4. Higher PLUS-M scores correspond with greater mobility. The T-score has a mean of 50 and a standard deviation (SD) of 10. A PLUS-M T-score of 50 represents the mean mobility reported by the development sample. A T-score greater than 57 indicates that the mobility is above the 75th percentile.

Time frame:: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Reported as:: Mean · units on a scale

Patient-perceived Mobility (PLUS-M)™
units on a scale	Baseline	Reference	Revo	Final
Patient-perceived Mobility (PLUS-M)™	57.2 ± 6.6	56.9 ± 7.4	58.3 ± 7.2	57.6 ± 7.1

Statistical analysis

Baseline vs Revo · Wilcoxon Signed Rank Test · p = 0.286 · Mean difference (final values): 1.02Difference represents Revo-M - Everyday Foot,

PrimaryPatient-perceived Activity Restrictions (Revised TAPES-AR Subscale)

Activity restrictions as measured by the Revised Trinity Amputation and Prosthesis Experience Scales Activity Restrictions subscale (TAPES-AR). The TAPES-AR subscale has 10 items on a three-point scale and the average score ranges from 0 to 2. A higher score indicates greater activity restriction.

Time frame:: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Reported as:: Mean · score on a scale

Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale)
score on a scale	Baseline	Reference	Revo	Final
Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale)	0.653 ± 0.362	0.686 ± 0.432	0.569 ± 0.399	0.674 ± 0.388

Statistical analysis

Baseline vs Revo · Wilcoxon Signed Rank Test · p = 0.031 · Mean difference (final values): -0.094Difference represents Revo-M - Everyday Foot.

SecondaryPercentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test

The percentage of subjects showing an improvement compared to baseline walking endurance as measured by the distance walked in the six minute walk test OR a decrease in the rating of perceived exertion (RPE) as measured by Borg CR100 while wearing the Revo-M. A clinically-significant improvement in the 6MWT is defined as a change in distance of greater than 45 meters. A clinically-significant improvement in the RPE is defined as a change greater than 10 points. The Borg CR100 scale has a minimum of 0 and a maximum of 100. Greater scores indicate higher perceived exertion.

Time frame:: 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Reported as:: Count of participants · Participants

Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test
Participants	Reference	Revo	Final
Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test	11	8	10

SecondaryPatient Perceived Balance Confidence (ABC)

Perception of balance confidence as measured by the extended Activities-specific Balance Confidence (ABC) Scale. The questionnaire provides a score that ranges from 0 to 100%. Higher scores indicate greater balance confidence.

Time frame:: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Reported as:: Mean · score on a scale

Patient Perceived Balance Confidence (ABC)
score on a scale	Baseline	Reference	Revo	Final
Patient Perceived Balance Confidence (ABC)	86.8 ± 8.9	86.2 ± 11.3	87.7 ± 11.2	86.9 ± 10.9

Statistical analysis

Baseline vs Revo · Wilcoxon Signed Rank Test · p = 0.421 · Mean difference (final values): 0.331Difference represents Revo-M - Everyday Foot.

SecondaryFunctional Satisfaction With Prosthesis (TAPES-FUN)

To characterize the level of functional satisfaction as measured by the TAPES Functional Satisfaction (TAPES-FUN) subscale while wearing a given prosthetic foot. There are 5 items scaled from 1 to 5. The subscale provides a total score that ranges from 5 to 25. Higher scores indicate greater functional satisfaction.

Time frame:: baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot
Reported as:: Mean · score on a scale

Functional Satisfaction With Prosthesis (TAPES-FUN)
score on a scale	Baseline	Reference	Revo	Final
Functional Satisfaction With Prosthesis (TAPES-FUN)	21.6 ± 4.3	21.5 ± 3.2	22.1 ± 2.3	20.4 ± 4.6

Statistical analysis

Baseline vs Revo · Wilcoxon Signed Rank Test · p = 0.443 · Mean difference (final values): 0.087Difference represents Revo-M - Everyday Foot.

Adverse events

Collected over Adverse events were collected during the four periods in the study. Each home-use period was between 6 to 10 weeks.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
Everyday Foot	0/26 (0%)	1/26 (3.8%)	3/26 (11.5%)
Reference Foot	0/22 (0%)	1/22 (4.5%)	7/22 (31.8%)
Revo-M	0/23 (0%)	2/23 (8.7%)	6/23 (26.1%)

Most frequent serious events

Most frequent serious events
Event	Everyday Foot	Reference Foot	Revo-M
COVID-19Infections and infestations	0/26	1/22	0/23
Bacterial InfectionInfections and infestations	0/26	0/22	1/23
CholecystectomySurgical and medical procedures	0/26	0/22	1/23
Intestinal blockageGastrointestinal disorders	1/26	0/22	0/23

Most frequent other events

Showing 10 of 13

Most frequent other events
Event	Everyday Foot	Reference Foot	Revo-M
Knee InstabilityProduct Issues	0/26	3/22	1/23
Back PainMusculoskeletal and connective tissue disorders	0/26	1/22	1/23
Muscle PainMusculoskeletal and connective tissue disorders	0/26	1/22	0/23
Pain in hipMusculoskeletal and connective tissue disorders	0/26	1/22	0/23
Chronic kidney diseaseRenal and urinary disorders	0/26	1/22	0/23
Injurious FallGeneral disorders	0/26	0/22	1/23
COVID-19Infections and infestations	0/26	0/22	1/23
Pain in legMusculoskeletal and connective tissue disorders	0/26	0/22	1/23
Loss of suctionProduct Issues	0/26	0/22	1/23
Open WoundSkin and subcutaneous tissue disorders	0/26	0/22	1/23

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
<=18 years	0	0	0	0	0
Between 18 and 65 years	2	5	4	4	15
>=65 years	4	3	0	4	11

Age, Continuous
Age, Continuous(years)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
Mean	64.2 ± 7.9	52.4 ± 16.8	44.8 ± 9.4	60.1 ± 23.5	56.3 ± 14.0

Sex: Female, Male
Sex: Female, Male(Participants)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
Female	0	2	1	2	5
Male	6	6	3	6	21

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
American Indian or Alaska Native	0	0	0	0	0
Asian	0	0	0	0	0
Native Hawaiian or Other Pacific Islander	0	0	0	0	0
Black or African American	1	2	0	1	4
White	5	6	4	7	22
More than one race	0	0	0	0	0
Unknown or Not Reported	0	0	0	0	0

Height
Height(centimeters)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
Mean	175.0 ± 4.3	170.5 ± 9.1	173.5 ± 8.7	176.1 ± 61.9	173.7 ± 7.6

Weight
Weight(kilograms)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
Mean	88.7 ± 14.1	78.0 ± 9.8	81.8 ± 7.2	92.1 ± 34.8	85.4 ± 13.4

Years since amputation
Years since amputation(years)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
Mean	11.8 ± 14.9	12.6 ± 14.8	22.0 ± 13.1	14.9 ± 16.3	16.2 ± 15.3

Amputation level
Amputation level(Participants)	Revo-M to Proflex XC	Proflex XC to Revo-M	Revo-M to Taleo	Taleo to Revo-M	Total
Transtibial	6	8	0	0	14
Transfemoral	0	0	4	8	12

1 further baseline measures are reported on the registry.

Study locations

4 sites

Artificial Limb Specialists
Mesa, Arizona 85202, United States
Dankmeyer Prosthetics & Orthotics
Linthicum, Maryland 21090, United States
Optimus Prosthetics
Dayton, Ohio 45414, United States
Ability P&O
Exton, Pennsylvania 19341, United States

References and documents

Publications

Gallagher P, Franchignoni F, Giordano A, MacLachlan M. Trinity amputation and prosthesis experience scales: a psychometric assessment using classical test theory and rasch analysis. Am J Phys Med Rehabil. 2010 Jun;89(6):487-96. doi: 10.1097/PHM.0b013e3181dd8cf1. PubMed 20489393 ↗
Hafner BJ, Morgan SJ, Askew RL, Salem R. Psychometric evaluation of self-report outcome measures for prosthetic applications. J Rehabil Res Dev. 2016;53(6):797-812. doi: 10.1682/JRRD.2015.12.0228. PubMed 28273329 ↗

Study documents

Protocol and statistical analysis plan ↗ · Jan 22, 2020

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No — There is no plan to share IPD.

Timeline

Tracking since Sep 25, 2026

ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Mar 2020 to primary completion in Mar 2022, 24 months.

Results were first posted in Sep 2024, 2 years 6 months after primary completion.

Of 53 industry-sponsored interventional studies with no phase under Wounds and Injuries, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 40. This study's 24 months is close to that.

Counting every sponsor, half of 599 studies reached it within 24 months; a quarter within 9 and three quarters within 48.

Wounds and Injuries covers many different conditions, not one, so the studies compared here vary widely. Read these figures as a rough guide.

How these figures are worked out, and which studies are left out of them.

Registered: Jan 17, 2020
First posted: Jan 27, 2020
StartActual: Mar 10, 2020
Primary completionActual: Mar 11, 2022
CompletionActual: Mar 11, 2022
Results first posted: Sep 23, 2024
Last update: Sep 23, 2024

What these dates mean

Start.: When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.: When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.: When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.: Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.

No changes since tracking began. The registry record was last updated on Sep 23, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04239222
Lead sponsor: Otto Bock Healthcare Products GmbH
Responsible party: Sponsor
First posted: Jan 27, 2020
Start date: Mar 10, 2020
Primary completion: Mar 11, 2022
Completion: Mar 11, 2022
Results posted: Sep 23, 2024
Last update: Sep 23, 2024

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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Feasibility Study to Evaluate a New Energy Storage and Return Prosthetic Foot

Study summary

Conditions studied

Browse trials for

Keywords

In context

Wounds and Injuries

Lead sponsor

Who can participate

✓Inclusion criteria

✕Exclusion criteria

Study design

Study arms

Interventions

What researchers measure

Primary outcomes

Secondary outcomes

Results

Participant flow

Outcome measures

Adverse events

Baseline characteristics

Study locations

References and documents

Publications

Study documents

Individual participant data

Timeline

Registry details

Key details

Oversight

Not currently enrolling

Follow this study

Discussion

Other studies in this condition

Other studies from this sponsor

Inclusion criteria

Exclusion criteria