Lower Limb Amputation Above Knee (Injury), Lower Limb Amputation Below Knee (Injury), Lower Limb Amputation Knee
Conditions
Keywords
Prosthetic foot, lower limb amputation
Brief 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.
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.
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
Sponsors
Otto Bock Healthcare Products GmbH
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Randomized cross-over controlled trial
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Person is 18 years or older. 2. Currently uses an energy storage and return foot. 3. Person has been a unilateral transfemoral (TF), or transtibial (TT) amputee using a prosthesis for at least 1 year. 4. For TF amputees, the person must be wearing an Ottobock Microprocessor-controlled Knee (MPK) with a compatible prosthetic foot 5. Person weighs ≤ 275 lbs (125 kg) size 26-27cm or ≤ 220 lbs (100 kg) size 24-25cm 6. Person is a K3 ambulator based on Medicare Functional Classification Level (MFCL). 7. Prosthetic foot size is 24 to 27 centimeters. 8. Socket Comfort Score of at least 7 9. Ability to read and understand English 10. A person is able and willing to give consent
Exclusion criteria
1. Current prosthetic foot is too old or worn out as assessed by the CPO. 2. TT subject with currently fit with a Proflex XC or TF subject currently fit with a Taleo. 3. Patient is pregnant or planning to become pregnant. 4. Person who has a life-threatening medical condition (i.e. terminal cancer, severe heart disease). 5. 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.). 6. Ulceration or skin breakdown of the residual limb. 7. Person currently has residual limb issues that significantly reduce their ability to load the prosthesis.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Patient-perceived Mobility (PLUS-M)™ | baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot | 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. |
| Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale) | baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test | 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot | 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. |
| Patient Perceived Balance Confidence (ABC) | baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot | 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. |
| Functional Satisfaction With Prosthesis (TAPES-FUN) | baseline, 2 months after fitting with reference foot, Revo-M, or crossover back to baseline foot | 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. |
Countries
United States
Participant flow
Pre-assignment details
1 Subject failed screening
Participants by arm
| Arm | Count |
|---|---|
| Revo-M to Proflex XC Transtibial amputees randomized to start with Revo-M and cross over to Proflex XC
Revo-M: Investigational energy storage and return prosthetic foot with using novel elastic elements.
Proflex XC: Commercially available carbon-fiber energy storage and return foot used as comparative foot for transtibial amputee subjects | 6 |
| Proflex XC to Revo-M Transtibial amputees randomized to start with Proflex XC and cross over to Revo-M
Revo-M: Investigational energy storage and return prosthetic foot with using novel elastic elements.
Proflex XC: Commercially available carbon-fiber energy storage and return foot used as comparative foot for transtibial amputee subjects | 8 |
| Revo-M to Taleo Transfemoral amputees randomized to start with Revo-M and cross over to Taleo
Revo-M: Investigational energy storage and return prosthetic foot with using novel elastic elements.
Taleo: Commercially available carbon-fiber energy storage and return foot used as comparative foot for transfemoral amputee subjects | 4 |
| Taleo to Revo-M Transfemoral amputees randomized to start with Taleo and cross over to Revo-M
Revo-M: Investigational energy storage and return prosthetic foot with using novel elastic elements.
Taleo: Commercially available carbon-fiber energy storage and return foot used as comparative foot for transfemoral amputee subjects | 8 |
| Total | 26 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 | FG003 |
|---|---|---|---|---|---|
| Baseline | Withdrawal by Subject | 0 | 0 | 1 | 1 |
| Crossover to Alternate Foot Assignment | Protocol Violation | 0 | 0 | 1 | 0 |
| First Foot Assignment | Withdrawal by Subject | 0 | 0 | 1 | 0 |
Baseline characteristics
| Characteristic | Revo-M to Proflex XC | Proflex XC to Revo-M | Revo-M to Taleo | Taleo to Revo-M | Total |
|---|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 4 Participants | 3 Participants | 0 Participants | 4 Participants | 11 Participants |
| Age, Categorical Between 18 and 65 years | 2 Participants | 5 Participants | 4 Participants | 4 Participants | 15 Participants |
| Age, Continuous | 64.2 years STANDARD_DEVIATION 7.9 | 52.4 years STANDARD_DEVIATION 16.8 | 44.8 years STANDARD_DEVIATION 9.4 | 60.1 years STANDARD_DEVIATION 23.5 | 56.3 years STANDARD_DEVIATION 14 |
| Amputation level Transfemoral | 0 Participants | 0 Participants | 4 Participants | 8 Participants | 12 Participants |
| Amputation level Transtibial | 6 Participants | 8 Participants | 0 Participants | 0 Participants | 14 Participants |
| Height | 175.0 centimeters STANDARD_DEVIATION 4.3 | 170.5 centimeters STANDARD_DEVIATION 9.1 | 173.5 centimeters STANDARD_DEVIATION 8.7 | 176.1 centimeters STANDARD_DEVIATION 61.9 | 173.7 centimeters STANDARD_DEVIATION 7.6 |
| Mobility grade K1 | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Mobility grade K2 | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Mobility grade K3 | 6 Participants | 8 Participants | 4 Participants | 8 Participants | 26 Participants |
| Mobility grade K4 | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 2 Participants | 0 Participants | 1 Participants | 4 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 5 Participants | 6 Participants | 4 Participants | 7 Participants | 22 Participants |
| Sex: Female, Male Female | 0 Participants | 2 Participants | 1 Participants | 2 Participants | 5 Participants |
| Sex: Female, Male Male | 6 Participants | 6 Participants | 3 Participants | 6 Participants | 21 Participants |
| Weight | 88.7 kilograms STANDARD_DEVIATION 14.1 | 78.0 kilograms STANDARD_DEVIATION 9.8 | 81.8 kilograms STANDARD_DEVIATION 7.2 | 92.1 kilograms STANDARD_DEVIATION 34.8 | 85.4 kilograms STANDARD_DEVIATION 13.4 |
| Years since amputation | 11.8 years STANDARD_DEVIATION 14.9 | 12.6 years STANDARD_DEVIATION 14.8 | 22.0 years STANDARD_DEVIATION 13.1 | 14.9 years STANDARD_DEVIATION 16.3 | 16.2 years STANDARD_DEVIATION 15.3 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 26 | 0 / 22 | 0 / 23 |
| other Total, other adverse events | 3 / 26 | 7 / 22 | 6 / 23 |
| serious Total, serious adverse events | 1 / 26 | 1 / 22 | 2 / 23 |
Outcome results
Primary
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
Population: ITT analysis
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Baseline | Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale) | 0.653 score on a scale | Standard Deviation 0.362 |
| Reference | Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale) | 0.686 score on a scale | Standard Deviation 0.432 |
| Revo | Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale) | 0.569 score on a scale | Standard Deviation 0.399 |
| Final | Patient-perceived Activity Restrictions (Revised TAPES-AR Subscale) | 0.674 score on a scale | Standard Deviation 0.388 |
Comparison: HO: μRevo-M ≥ μEveryday, μRevo-M is the mean TAPES-AR score using the Revo-M and μEveryday is the mean TAPES-AR score using the Everyday foot at baseline.p-value: 0.031Wilcoxon Signed Rank Test
Primary
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
Population: ITT analysis
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Baseline | Patient-perceived Mobility (PLUS-M)™ | 57.2 units on a scale | Standard Deviation 6.6 |
| Reference | Patient-perceived Mobility (PLUS-M)™ | 56.9 units on a scale | Standard Deviation 7.4 |
| Revo | Patient-perceived Mobility (PLUS-M)™ | 58.3 units on a scale | Standard Deviation 7.2 |
| Final | Patient-perceived Mobility (PLUS-M)™ | 57.6 units on a scale | Standard Deviation 7.1 |
Comparison: HO: μRevo-M ≤ μEveryday, μRevo-M is the mean PLUS-M score using the Revo-M and μEveryday is the mean PLUS-M score using the Everyday foot at baseline.p-value: 0.286Wilcoxon Signed Rank Test
Secondary
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
Population: ITT analysis
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Baseline | Functional Satisfaction With Prosthesis (TAPES-FUN) | 21.6 score on a scale | Standard Deviation 4.3 |
| Reference | Functional Satisfaction With Prosthesis (TAPES-FUN) | 21.5 score on a scale | Standard Deviation 3.2 |
| Revo | Functional Satisfaction With Prosthesis (TAPES-FUN) | 22.1 score on a scale | Standard Deviation 2.3 |
| Final | Functional Satisfaction With Prosthesis (TAPES-FUN) | 20.4 score on a scale | Standard Deviation 4.6 |
Comparison: HO: μRevo-M ≤ μEveryday, μRevo-M is the mean TAPES-FUN score using the Revo-M and μEveryday is the mean TAPES-FUN score using the Everyday foot at baseline.p-value: 0.443Wilcoxon Signed Rank Test
Secondary
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
Population: ITT analysis
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Baseline | Patient Perceived Balance Confidence (ABC) | 86.8 score on a scale | Standard Deviation 8.9 |
| Reference | Patient Perceived Balance Confidence (ABC) | 86.2 score on a scale | Standard Deviation 11.3 |
| Revo | Patient Perceived Balance Confidence (ABC) | 87.7 score on a scale | Standard Deviation 11.2 |
| Final | Patient Perceived Balance Confidence (ABC) | 86.9 score on a scale | Standard Deviation 10.9 |
Comparison: HO: μRevo-M ≤ μEveryday, μRevo-M is the mean ABC score using the Revo-M and μEveryday is the mean ABC score using the Everyday foot at baseline.p-value: 0.421Wilcoxon Signed Rank Test
Secondary
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
Population: ITT analysis
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Baseline | Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test | 11 Participants |
| Reference | Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test | 8 Participants |
| Revo | Percentage of Subjects Showing Improvement in Walking Endurance or Perceived Exertion in the 6-minute Walk Test | 10 Participants |