Trial Outcomes & Findings for Assist-Knee: Energy-Harvesting Knee Prosthesis (NCT NCT04023045)

NCT ID: NCT04023045

Last Updated: 2023-10-18

Results Overview

The amount of time, measured in seconds, needed by the subject to complete the sit-to-stand transition. At least four trials of the sit-to-stand maneuver were collected for each participant using a motion analysis system. Average and standard deviation of the time to complete the sit-to-stand transition were calculated for each participant (each participant served as their own control in this pilot study). The start of the transition was determined by participant initiation; the end of the transition was determined by the participant reaching full knee extension.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

3 participants

Primary outcome timeframe

Collection at baseline

Results posted on

2023-10-18

Participant Flow

Individuals were recruited from a sample of convenience in the local area between 07/15/2019 and 02/26/2020.

Participant milestones

Participant milestones
Measure
Habitual Prosthesis
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 1)
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 1: First set of settings tested on Assist-Knee with the participant.
Assist-Knee (Settings 2)
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
Habitual Prosthesis Condition
STARTED
3
0
0
Habitual Prosthesis Condition
COMPLETED
3
0
0
Habitual Prosthesis Condition
NOT COMPLETED
0
0
0
Assist-Knee (Settings 1) Condition
STARTED
0
3
0
Assist-Knee (Settings 1) Condition
COMPLETED
0
3
0
Assist-Knee (Settings 1) Condition
NOT COMPLETED
0
0
0
Assist-Knee (Settings 2) Condition
STARTED
0
0
3
Assist-Knee (Settings 2) Condition
COMPLETED
0
0
3
Assist-Knee (Settings 2) Condition
NOT COMPLETED
0
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Assist-Knee: Energy-Harvesting Knee Prosthesis

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Study Participants
n=3 Participants
Study participants completed both arms of the study: Habitual and Assist-Knee. Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician. Assist-Knee Prosthesis: Assist-Knee is an experimental lower limb knee prosthesis.
Age, Categorical
<=18 years
0 Participants
n=5 Participants
Age, Categorical
Between 18 and 65 years
1 Participants
n=5 Participants
Age, Categorical
>=65 years
2 Participants
n=5 Participants
Age, Continuous
69 years
STANDARD_DEVIATION 5 • n=5 Participants
Sex: Female, Male
Female
2 Participants
n=5 Participants
Sex: Female, Male
Male
1 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
3 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 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
0 Participants
n=5 Participants
Race (NIH/OMB)
White
3 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
Region of Enrollment
United States
3 participants
n=5 Participants

PRIMARY outcome

Timeframe: Collection at baseline

Population: Each participant served as their own control in this analysis.

The amount of time, measured in seconds, needed by the subject to complete the sit-to-stand transition. At least four trials of the sit-to-stand maneuver were collected for each participant using a motion analysis system. Average and standard deviation of the time to complete the sit-to-stand transition were calculated for each participant (each participant served as their own control in this pilot study). The start of the transition was determined by participant initiation; the end of the transition was determined by the participant reaching full knee extension.

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Time to Complete Sit-to-Stand
Participant A
1.6 seconds
Standard Deviation 0.1
Time to Complete Sit-to-Stand
Participant B
2.2 seconds
Standard Deviation 0.2
Time to Complete Sit-to-Stand
Participant C
1.4 seconds
Standard Deviation 0.2

PRIMARY outcome

Timeframe: After acclimation to Assist-Knee (Participants are given at least 10 minutes and no more than 60 minutes to acclimate to each Assist-Knee condition for safety. After acclimating, participants will complete the maneuver to measure this outcome.)

Population: Each participant served as their own control in this analysis.

The amount of time, measured in seconds, needed by the subject to complete the sit-to-stand transition. At least four trials of the sit-to-stand maneuver were collected for each participant using a motion analysis system. Average and standard deviation of the time to complete the sit-to-stand transition were calculated for each participant (each participant served as their own control in this pilot study). The start of the transition was determined by participant initiation; the end of the transition was determined by the participant reaching full knee extension.

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
n=3 Participants
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Time to Complete Sit-to-Stand
Participant A
3.4 seconds
Standard Deviation 0.6
2.7 seconds
Standard Deviation 0.2
Time to Complete Sit-to-Stand
Participant B
6.4 seconds
Standard Deviation 1.3
3.8 seconds
Standard Deviation 0.5
Time to Complete Sit-to-Stand
Participant C
2.4 seconds
Standard Deviation 0.5
2.9 seconds
Standard Deviation 0.5

SECONDARY outcome

Timeframe: Collection at baseline

Population: Each participant served as their own control in this analysis.

The Timed Up and Go (TUG) test is a validated timed functional test that involves standing up from a chair, walking forward for 3 meters, turning around, walking back to the chair for 3 meter, and sitting down. Each participant completed the TUG test for three trials. Time was measured using a stopwatch. Average and standard deviation of the time to complete the TUG test were calculated for each participant (each participant served as their own control in this pilot study).

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Timed Up and Go (TUG) Test
Participant A
7.1 seconds
Standard Deviation 0.5
Timed Up and Go (TUG) Test
Participant B
13.7 seconds
Standard Deviation 1.0
Timed Up and Go (TUG) Test
Participant C
12.3 seconds
Standard Deviation 0.8

SECONDARY outcome

Timeframe: After acclimation to Assist-Knee (Participants are given at least 10 minutes and no more than 60 minutes to acclimate to each Assist-Knee condition for safety. After acclimating, participants will complete the maneuver to measure this outcome.)

Population: Each participant served as their own control in this analysis.

The Timed Up and Go (TUG) test is a validated timed functional test that involves standing up from a chair, walking forward for 3 meters, turning around, walking back to the chair for 3 meter, and sitting down. Each participant completed the TUG test for three trials. Time was measured using a stopwatch. Average and standard deviation of the time to complete the TUG test were calculated for each participant (each participant served as their own control in this pilot study).

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
n=3 Participants
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Timed Up and Go (TUG) Test
Participant A
12.3 seconds
Standard Deviation 1.1
12.8 seconds
Standard Deviation 0.8
Timed Up and Go (TUG) Test
Participant B
25.0 seconds
Standard Deviation 3.0
22.0 seconds
Standard Deviation 1.4
Timed Up and Go (TUG) Test
Participant C
20.8 seconds
Standard Deviation 3.5
18.8 seconds
Standard Deviation 1.5

SECONDARY outcome

Timeframe: Collection at baseline

Population: Each participant served as their own control in this analysis.

The amount of time, measured in seconds, needed by the subject to complete the stand-to-sit transition. At least four trials of the stand-to-sit maneuver were collected for each participant using a motion analysis system. Average and standard deviation of the time to complete the stand-to-sit transition were calculated for each participant (each participant served as their own control in this pilot study). The start of the transition was determined by participant initiation; the end of the transition was determined by the participant being seated on a chair.

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Time to Complete Stand-to-Sit
Participant A
2.7 seconds
Standard Deviation 0.1
Time to Complete Stand-to-Sit
Participant B
4.1 seconds
Standard Deviation 1.0
Time to Complete Stand-to-Sit
Participant C
1.6 seconds
Standard Deviation 0.2

SECONDARY outcome

Timeframe: After acclimation to Assist-Knee (Participants are given at least 10 minutes and no more than 60 minutes to acclimate to each Assist-Knee condition for safety. After acclimating, participants will complete the maneuver to measure this outcome.)

Population: Each participant served as their own control in this analysis.

The amount of time, measured in seconds, needed by the subject to complete the stand-to-sit transition. At least four trials of the stand-to-sit maneuver were collected for each participant using a motion analysis system. Average and standard deviation of the time to complete the stand-to-sit transition were calculated for each participant (each participant served as their own control in this pilot study). The start of the transition was determined by participant initiation; the end of the transition was determined by the participant being seated on a chair.

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
n=3 Participants
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Time to Complete Stand-to-Sit
Participant C
2.5 seconds
Standard Deviation 0.1
2.7 seconds
Standard Deviation 0.7
Time to Complete Stand-to-Sit
Participant A
4.4 seconds
Standard Deviation 0.4
3.3 seconds
Standard Deviation 0.4
Time to Complete Stand-to-Sit
Participant B
4.9 seconds
Standard Deviation 1.7
4.5 seconds
Standard Deviation 0.9

SECONDARY outcome

Timeframe: Collection at baseline

Population: Each participant served as their own control in this analysis.

The percentage of body weight on the contralateral limb was determined for both stand-to-sit and sit-to-stand transitions at 65 degrees knee flexion. A force plate under the contralateral limb recorded the amount of loading on the limb during the stand-to-sit and sit-to-stand transitions. The amount of contralateral limb loading at 65 degrees knee flexion was determined and divided by the participant's total loading due to overall body weight. This value was then converted to a percentage.

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
n=3 Participants
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Percentage of Body Weight on Contralateral Limb at 65 Degrees Knee Flexion
Participant A
79.2 % body weight
Standard Deviation 2.8
85.9 % body weight
Standard Deviation 2.5
Percentage of Body Weight on Contralateral Limb at 65 Degrees Knee Flexion
Participant B
61.8 % body weight
Standard Deviation 11.4
49.0 % body weight
Standard Deviation 2.3
Percentage of Body Weight on Contralateral Limb at 65 Degrees Knee Flexion
Participant C
87.0 % body weight
Standard Deviation 3.6
95.8 % body weight
Standard Deviation 2.6

SECONDARY outcome

Timeframe: After acclimation to Assist-Knee (Participants are given at least 10 minutes and no more than 60 minutes to acclimate to each Assist-Knee condition for safety. After acclimating, participants will complete the maneuver to measure this outcome.)

Population: Each participant served as their own control in this analysis.

The percentage of body weight on the contralateral limb was determined for both stand-to-sit and sit-to-stand transitions at 65 degrees knee flexion. A force plate under the contralateral limb recorded the amount of loading on the limb during the stand-to-sit and sit-to-stand transitions. The amount of contralateral limb loading at 65 degrees knee flexion was determined and divided by the participant's total loading due to overall body weight. This value was then converted to a percentage.

Outcome measures

Outcome measures
Measure
Habitual Prosthesis
n=3 Participants
Participant's prescribed prosthesis Habitual Prosthesis: Habitual baseline prosthesis prescribed by participant's clinician.
Assist-Knee (Settings 2)
n=3 Participants
Experimental knee prosthesis Assist-Knee: Assist-Knee is an experimental lower limb knee prosthesis. Settings 2: Second set of settings tested on Assist-Knee with the participant.
SIT With Assist-Knee (Settings 2)
n=3 Participants
Contralateral limb weight distribution during stand-to-sit at 65 degrees knee flexion when using Assist-Knee (Settings 2).
STAND With Assist-Knee (Settings 2)
n=3 Participants
Contralateral limb weight distribution during sit-to-stand at 65 degrees knee flexion when using Assist-Knee (Settings 2).
Percentage of Body Weight on Contralateral Limb at 65 Degrees Knee Flexion
Participant A
67.7 % body weight
Standard Deviation 7.5
82.0 % body weight
Standard Deviation 1.9
48.0 % body weight
Standard Deviation 9.4
83.5 % body weight
Standard Deviation 1.2
Percentage of Body Weight on Contralateral Limb at 65 Degrees Knee Flexion
Participant B
23.5 % body weight
Standard Deviation 13.7
27.0 % body weight
Standard Deviation 6.9
19.4 % body weight
Standard Deviation 10.4
31.3 % body weight
Standard Deviation 2.3
Percentage of Body Weight on Contralateral Limb at 65 Degrees Knee Flexion
Participant C
67.0 % body weight
Standard Deviation 1.6
78.6 % body weight
Standard Deviation 4.5
63.4 % body weight
Standard Deviation 9.9
76.4 % body weight
Standard Deviation 3.2

Adverse Events

Study Participants

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

Sarah Chang

Orthocare Innovations, LLC

Phone: 425-771-0797

Results disclosure agreements

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