Trial Outcomes & Findings for Determining the Potential Benefit of Powered Prostheses (NCT NCT02828982)

NCT ID: NCT02828982

Last Updated: 2022-01-18

Results Overview

Metabolic costs will be measured using a portable metabolic system when participants walk on a treadmill at a fixed speed.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

12 participants

Primary outcome timeframe

Testing took place after wearing the prostheses for two weeks

Results posted on

2022-01-18

Participant Flow

Recruitment began after initial approval from the University of Michigan IRB (July 2016). Participants were recruited through the University of Michigan Orthotics and Prosthetics Clinic by a study physician and study prosthetist in-person, through phone or email, or with flyers.

Participants were asked to complete both arms of the study. Before starting, participants were randomly enrolled in the dynamic response foot (unpowered prosthesis) or powered condition to start with. Some participants completed both arms while others only finished one of the arms.

Participant milestones

Participant milestones
Measure
Powered Ankle Prosthesis, Then Unpowered Prosthesis
In this condition, the participant was fitted with a powered prosthetic ankle by a certified prosthetist to start the study. The ankle is the BiOM which is manufactured by Bionx (which used to be named iWalk). This device was given 510(K) Exempt status by the FDA under (regulation number: 890.3500). Participants had at least one week to acclimate to the prosthesis. They then will wore the device for 2 weeks at home, while their activity was monitored. They then came to the lab for testing. The powered prosthesis was removed and their prescribed prosthetic foot was reattached to their existing socket. They then wore their prescribed prosthesis for 2 weeks, while their activity was monitored, before returning to the lab for testing.
Unpowered Prosthesis, Then Powered Ankle Prosthesis
In this arm, participants will start in their clinically prescribed dynamic response foot. They first wore their prescribed prosthesis for 2 weeks, while their activity was monitored. They then came to the laboratory for testing. Participants were then fitted with a powered prosthetic ankle by a certified prosthetist. The ankle is the BiOM which is manufactured by Bionx (which used to be named iWalk). This device was given 510(K) Exempt status by the FDA under (regulation number: 890.3500). Participants had at least one week to acclimate to the prosthesis. They then will wore the device for 2 weeks at home, while their activity was monitored. They then came to the lab for testing. The powered prosthesis was removed and their prescribed prosthetic foot was reattached to their existing socket.
First Intervention (3 Weeks)
STARTED
5
7
First Intervention (3 Weeks)
Received Intervention
5
7
First Intervention (3 Weeks)
COMPLETED
4
6
First Intervention (3 Weeks)
NOT COMPLETED
1
1
Second Intervention (3 Weeks)
STARTED
4
6
Second Intervention (3 Weeks)
Received Intervention
4
6
Second Intervention (3 Weeks)
COMPLETED
4
6
Second Intervention (3 Weeks)
NOT COMPLETED
0
0

Reasons for withdrawal

Reasons for withdrawal
Measure
Powered Ankle Prosthesis, Then Unpowered Prosthesis
In this condition, the participant was fitted with a powered prosthetic ankle by a certified prosthetist to start the study. The ankle is the BiOM which is manufactured by Bionx (which used to be named iWalk). This device was given 510(K) Exempt status by the FDA under (regulation number: 890.3500). Participants had at least one week to acclimate to the prosthesis. They then will wore the device for 2 weeks at home, while their activity was monitored. They then came to the lab for testing. The powered prosthesis was removed and their prescribed prosthetic foot was reattached to their existing socket. They then wore their prescribed prosthesis for 2 weeks, while their activity was monitored, before returning to the lab for testing.
Unpowered Prosthesis, Then Powered Ankle Prosthesis
In this arm, participants will start in their clinically prescribed dynamic response foot. They first wore their prescribed prosthesis for 2 weeks, while their activity was monitored. They then came to the laboratory for testing. Participants were then fitted with a powered prosthetic ankle by a certified prosthetist. The ankle is the BiOM which is manufactured by Bionx (which used to be named iWalk). This device was given 510(K) Exempt status by the FDA under (regulation number: 890.3500). Participants had at least one week to acclimate to the prosthesis. They then will wore the device for 2 weeks at home, while their activity was monitored. They then came to the lab for testing. The powered prosthesis was removed and their prescribed prosthetic foot was reattached to their existing socket.
First Intervention (3 Weeks)
Withdrawal by Subject
1
1

Baseline Characteristics

Determining the Potential Benefit of Powered Prostheses

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
All Study Participants
n=12 Participants
This group represents all participants enrolled in the study.
Age, Continuous
50.27 years
STANDARD_DEVIATION 13.21 • n=5 Participants
Sex: Female, Male
Female
0 Participants
n=5 Participants
Sex: Female, Male
Male
12 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
12 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
1 Participants
n=5 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
3 Participants
n=5 Participants
Race (NIH/OMB)
White
8 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants

PRIMARY outcome

Timeframe: Testing took place after wearing the prostheses for two weeks

Population: Each participant wore both study prostheses. One participant was excluded from analysis as he was not able to reach steady-state energetics on a treadmill

Metabolic costs will be measured using a portable metabolic system when participants walk on a treadmill at a fixed speed.

Outcome measures

Outcome measures
Measure
Unpowered Prosthesis
n=9 Participants
This condition is any unpowered prosthesis that was clinically prescribed to the patient
BiOM Powered Prosthesis
n=9 Participants
This device is a prosthetic ankle which is battery powered and supplies active ankle power.
Metabolic Cost of Walking
0.409 J/Nm
Standard Deviation 0.040
0.397 J/Nm
Standard Deviation 0.078

PRIMARY outcome

Timeframe: 2 weeks

Population: Each participant in the study wore both prostheses

Activity data we be collected using activity monitors and GPS with both the regular prosthesis and the powered ankle prosthesis. Each activity monitoring period will last 2 weeks and will be done within in a 2 month period. Daily step count taken outside of the home, determined using an activity monitor and GPS device

Outcome measures

Outcome measures
Measure
Unpowered Prosthesis
n=10 Participants
This condition is any unpowered prosthesis that was clinically prescribed to the patient
BiOM Powered Prosthesis
n=10 Participants
This device is a prosthetic ankle which is battery powered and supplies active ankle power.
Total Steps Outside the Home Over a Two Week Period
2030 steps
Standard Deviation 1440
1640 steps
Standard Deviation 1100

PRIMARY outcome

Timeframe: Questionnaire completed 2 weeks after wearing each prosthesis

Population: Each participant in the study wore both prostheses

Participants completed the Medical Outcomes Study 36 Items Short-Form Health Survey (SF-36) after each condition. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score the more disability.

Outcome measures

Outcome measures
Measure
Unpowered Prosthesis
n=10 Participants
This condition is any unpowered prosthesis that was clinically prescribed to the patient
BiOM Powered Prosthesis
n=10 Participants
This device is a prosthetic ankle which is battery powered and supplies active ankle power.
Quality of Life (QoL) on a Short-Form 36
Physical Component Score
62.9 scores on a scale
Standard Deviation 17.5
59.4 scores on a scale
Standard Deviation 22
Quality of Life (QoL) on a Short-Form 36
Mental Component Score
63.6 scores on a scale
Standard Deviation 19.1
67.4 scores on a scale
Standard Deviation 24.0

SECONDARY outcome

Timeframe: Questionnaire completed 2 weeks after wearing each prosthesis

Population: Each participant wore both study prostheses.

Participants completed a survey to evaluate their prosthetic satisfaction (Prosthetic Evaluation Questionnaire) after each condition. Most questions in the PEQ use a visual analog scale format. Each visual analog scale is scored as a continuous numerical variable measured as the distance in millimeters from the left endpoint of the line (0 mm) to the point at which the respondent's mark crosses the line (up to 100 mm). The questions are all worded so that a higher number (toward the right) will correspond with a more positive response. Ambulation - Greater number = increased perceived ambulation Appearance - Greater number = better appearance Frustration - Greater number = less frustration Perceived Response - Greater number = increased perceived response Residual Limb Health - Greater number = better residual limb health Social burden - Greater number = less social burden Sounds - Greater number = less sound Utility - Greater

Outcome measures

Outcome measures
Measure
Unpowered Prosthesis
n=10 Participants
This condition is any unpowered prosthesis that was clinically prescribed to the patient
BiOM Powered Prosthesis
n=10 Participants
This device is a prosthetic ankle which is battery powered and supplies active ankle power.
Prosthetic Evaluation Questionnaire (PEQ)
Ambulation
75.2 scores on a scale
Standard Deviation 18.3
84.0 scores on a scale
Standard Deviation 15.8
Prosthetic Evaluation Questionnaire (PEQ)
Appearance
85.6 scores on a scale
Standard Deviation 9.58
80.6 scores on a scale
Standard Deviation 12.8
Prosthetic Evaluation Questionnaire (PEQ)
Frustration
66.8 scores on a scale
Standard Deviation 29.7
84.8 scores on a scale
Standard Deviation 27.8
Prosthetic Evaluation Questionnaire (PEQ)
Perceived Response
87.6 scores on a scale
Standard Deviation 20.7
97.1 scores on a scale
Standard Deviation 4.33
Prosthetic Evaluation Questionnaire (PEQ)
Residual Limb Health
73.6 scores on a scale
Standard Deviation 19.4
79.9 scores on a scale
Standard Deviation 14.3
Prosthetic Evaluation Questionnaire (PEQ)
Social Burden
85.2 scores on a scale
Standard Deviation 19.5
91.6 scores on a scale
Standard Deviation 15.3
Prosthetic Evaluation Questionnaire (PEQ)
Sounds
71.4 scores on a scale
Standard Deviation 27.1
57.2 scores on a scale
Standard Deviation 31.5
Prosthetic Evaluation Questionnaire (PEQ)
Utility
73.1 scores on a scale
Standard Deviation 14.8
74.4 scores on a scale
Standard Deviation 16.7
Prosthetic Evaluation Questionnaire (PEQ)
Well-Being
72.9 scores on a scale
Standard Deviation 26.9
79.2 scores on a scale
Standard Deviation 22.0

SECONDARY outcome

Timeframe: Testing took place after the participant wore the prosthesis for 2 weeks

Population: Each participant wore both study prostheses

Participants walk on a treadmill while muscle activity from various lower limb muscles are monitored using electromyography. We calculated the integrated EMG (iEMG) for each muscle collected as the total activity in that muscle as a percentage of the maximum signal.

Outcome measures

Outcome measures
Measure
Unpowered Prosthesis
n=9 Participants
This condition is any unpowered prosthesis that was clinically prescribed to the patient
BiOM Powered Prosthesis
n=9 Participants
This device is a prosthetic ankle which is battery powered and supplies active ankle power.
Muscle Activity in the Lower Limb
Intact side biceps femoris
24.3 percentage of maximum signal
Standard Deviation 5.07
24.1 percentage of maximum signal
Standard Deviation 8.83
Muscle Activity in the Lower Limb
Intact side rectus femoris
25.3 percentage of maximum signal
Standard Deviation 4.06
28.7 percentage of maximum signal
Standard Deviation 14.1
Muscle Activity in the Lower Limb
Intact side soleus
29.9 percentage of maximum signal
Standard Deviation 6.47
28.6 percentage of maximum signal
Standard Deviation 9.11
Muscle Activity in the Lower Limb
Intact side tibialis anterior
28.4 percentage of maximum signal
Standard Deviation 10.2
30.4 percentage of maximum signal
Standard Deviation 7.99
Muscle Activity in the Lower Limb
Residual side biceps femoris
27.8 percentage of maximum signal
Standard Deviation 10.8
25.9 percentage of maximum signal
Standard Deviation 8.70
Muscle Activity in the Lower Limb
Residual side rectus femoris
38.3 percentage of maximum signal
Standard Deviation 12.2
41.3 percentage of maximum signal
Standard Deviation 9.01

SECONDARY outcome

Timeframe: Testing took place after wearing the prostheses for two weeks

Population: Each participant wore both study prostheses

Participants walk on a treadmill at a fast speed until they felt they can no longer continue. The time to fatigue was recorded.

Outcome measures

Outcome measures
Measure
Unpowered Prosthesis
n=10 Participants
This condition is any unpowered prosthesis that was clinically prescribed to the patient
BiOM Powered Prosthesis
n=10 Participants
This device is a prosthetic ankle which is battery powered and supplies active ankle power.
Time to Fatigue
14.7 minutes
Standard Deviation 12.1
13.2 minutes
Standard Deviation 10.8

Adverse Events

Powered Ankle Prosthesis

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Unpowered Prosthesis

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Deanna Gates

University of Michigan

Phone: (734) 647-2698

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place