Trial Outcomes & Findings for Clinical Outcomes With Passive MPKs vs. Powered Prosthetic Knees (NCT NCT05267639)

Last Updated: 2025-06-26

Results Overview

Prior to each condition, each subject will be fit and aligned on the designated knee by a trained certified prosthetist. An activity monitor (such as the GeneActiv™) will be worn by the subject for each intervention period during the final month of the condition. Similar to prior studies, the investigators will use the activity monitor to track the number of steps the subjects take in each condition per day. The number of steps per day are averaged over the final month in each condition. A higher value indicates a better outcome.

Recruitment status

COMPLETED

Study phase

Target enrollment

13 participants

Primary outcome timeframe

1 Month

Results posted on

2025-06-26

Participant Flow

Participant milestones

Participant milestones
Measure	Control (MPK), Then Power Knee The subject uses their usual Microprocessor Knee (MPK) for 3 months, and then uses the Ossur Power Knee for the following 3 months. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.	Power Knee, Then Control (MPK) The subject uses the Ossur PK in place of their usual MPK for 3 months, and then uses their usual Microprocessor Knee (MPK) for the following 3 months. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.
Overall Study STARTED	7	6
Overall Study COMPLETED	6	6
Overall Study NOT COMPLETED	1	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Control (MPK), Then Power Knee The subject uses their usual Microprocessor Knee (MPK) for 3 months, and then uses the Ossur Power Knee for the following 3 months. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.	Power Knee, Then Control (MPK) The subject uses the Ossur PK in place of their usual MPK for 3 months, and then uses their usual Microprocessor Knee (MPK) for the following 3 months. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.
Overall Study Withdrawal by Subject	1	0

Baseline Characteristics

Clinical Outcomes With Passive MPKs vs. Powered Prosthetic Knees

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Control (MPK), Then Power Knee n=7 Participants The subject uses their usual Microprocessor Knee (MPK) for 3 months, and then uses the Ossur Power Knee for the following 3 months. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.	Power Knee, Then Control (MPK) n=6 Participants The subject uses the Ossur PK in place of their usual MPK for 3 months, and then uses their usual Microprocessor Knee (MPK) for the following 3 months. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.	Total n=13 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	5 Participants n=5 Participants	5 Participants n=7 Participants	10 Participants n=5 Participants
Age, Categorical >=65 years	2 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants
Sex: Female, Male Female	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Sex: Female, Male Male	7 Participants n=5 Participants	5 Participants n=7 Participants	12 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=5 Participants	2 Participants n=7 Participants	2 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	6 Participants n=5 Participants	3 Participants n=7 Participants	9 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) White	6 Participants n=5 Participants	5 Participants n=7 Participants	11 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Region of Enrollment United States	7 participants n=5 Participants	6 participants n=7 Participants	13 participants n=5 Participants

PRIMARY outcome

Timeframe: 1 Month

Population: 13 total participants. 1 participant withdrew (no data in either condition). Comparator Baseline: no data from withdrawn participant. Power Knee: step count successfully collected from 2 participants. 8 participants transitioned early and did not make it to the final month for collection. 1 activity monitor was lost in the mail. 1 file was unable to be processed/corrupt.

Outcome measures

Outcome measures
Measure	Control (MPK) n=12 Participants The subject will wear their usual Microprocessor Knee (MPK) for 3 months, as well as in the lab to complete outcome measures.	Power Knee n=2 Participants The subject will wear the Ossur PK in place of their usual MPK for 3 months, as well as in the lab to complete outcome measures. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.
Daily Step Count	5747 Steps/day Standard Deviation 3212	3162 Steps/day Standard Deviation 1031

PRIMARY outcome

Timeframe: At the end of each 3 month condition

Population: 13 total enrolled. 1 participant withdrew (no data in either condition). Comparator Baseline: 1 participant withdrew from PK condition before collecting ABC. 11 analyzed.

Activities-specific balance confidence (ABC) scale is a structured questionnaire that measures an individual's confidence during ambulatory activities without falling or experiencing a sense of unsteadiness. It consists of 16 questions gauging the individual's confidence while doing activities, from 0 (no confidence) to 4 (complete confidence). Therefore, the total score ranges from 0 to 64, with a higher value indicating a better outcome. This survey will be given at the end of each study condition (2 conditions, 3 months per condition). This survey will be administered as a part of the master questionnaire. Analysis is reported in % of balance confidence, which is found by taking their average of all questions (sum up all questions and divide by total number of questions) and dividing that average by 4.

Outcome measures

Outcome measures
Measure	Control (MPK) n=11 Participants The subject will wear their usual Microprocessor Knee (MPK) for 3 months, as well as in the lab to complete outcome measures.	Power Knee n=12 Participants The subject will wear the Ossur PK in place of their usual MPK for 3 months, as well as in the lab to complete outcome measures. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.
Activities-Specific Balance Confidence Scale (ABC) - Measuring Change From Baseline	83 Percentage of balance confidence Standard Deviation 17	83 Percentage of balance confidence Standard Deviation 15

PRIMARY outcome

Timeframe: At the end of each 3 month condition

Population: 13 total enrolled. 1 participant withdrew (no data in either condition). Comparator Baseline: 1 participant withdrew from PK condition before collecting ABC. 11 analyzed.

The version of the PEQ which will be administered consists of 2 questions in 1 category (well being). For purposes of easier administration, the investigators have adopted the modified 10-point ordinal scale version of the PEQ-WB (scale 1-10, where 1 is the worst and 10 is the best relative to the questions being asked). This survey will be given at the end of each study condition (2 conditions, 3 months per condition). This survey will be administered as a part of the master questionnaire. The reported result is the average of the 2 questions in the PEQ-WB. The range of this reported result is 1-10, where a higher value indicates a better outcome.

Outcome measures

Outcome measures
Measure	Control (MPK) n=12 Participants The subject will wear their usual Microprocessor Knee (MPK) for 3 months, as well as in the lab to complete outcome measures.	Power Knee n=11 Participants The subject will wear the Ossur PK in place of their usual MPK for 3 months, as well as in the lab to complete outcome measures. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.
PEQ-Well Being (PEQ-WB) - Measuring Change From Baseline	8.3 score on a scale Standard Deviation 1.6	8.0 score on a scale Standard Deviation 1.5

Adverse Events

Control (MPK)

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Power Knee

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Control (MPK) n=13 participants at risk The subject will wear their usual Microprocessor Knee (MPK) for 3 months, as well as in the lab to complete outcome measures.	Power Knee n=13 participants at risk The subject will wear the Ossur PK in place of their usual MPK for 3 months, as well as in the lab to complete outcome measures. Power Knee: Newest version of the commercially-available Power Knee developed by Ossur.
Skin and subcutaneous tissue disorders Phantom Limb Pain	0.00% 0/13 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.	7.7% 1/13 • Number of events 1 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.
Musculoskeletal and connective tissue disorders Broken finger	7.7% 1/13 • Number of events 1 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.	0.00% 0/13 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.
Skin and subcutaneous tissue disorders Fall	0.00% 0/13 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.	7.7% 1/13 • Number of events 1 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.
Skin and subcutaneous tissue disorders Ankle swelling	7.7% 1/13 • Number of events 1 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.	0.00% 0/13 • Adverse events were monitored/collected during each condition. With each condition lasting about 3 months, each participant was monitored for adverse events for about 6 months total. Adverse events were monitored/assessed at least every 2 weeks by phone call, with study staff checking in more frequently if participants reached out with questions. Participants were told to reach out to study staff immediately if adverse events did occur.

Additional Information

Jen Johansson

Liberating Technologies, Inc.

Phone: 774-233-0874

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place