Trial Outcomes & Findings for Clinical Investigation (Beta) of a New Developed Prosthetic Knee (NCT NCT06748729)

NCT ID: NCT06748729

Last Updated: 2025-09-04

Results Overview

Satisfaction on ramp descent with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 11 participants
• Primary outcome timeframe: After 4 weeks of use
• Results posted on: 2025-09-04

Participant Flow

Participant milestones

Measure	Exploratory Testing of a New Prosthetic Knee Navii Knee: Microprocessor controlled prosthetic knee (MPK)
Overall Study STARTED	11
Overall Study COMPLETED	10
Overall Study NOT COMPLETED	1

Reasons for withdrawal

Measure	Exploratory Testing of a New Prosthetic Knee Navii Knee: Microprocessor controlled prosthetic knee (MPK)
Overall Study Withdrawal by Subject	1

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Measure	Exploratory Testing of a New Prosthetic Knee n=11 Participants Navii Knee: Microprocessor controlled prosthetic knee (MPK)
Age, Categorical <=18 years	0 Participants n=11 Participants
Age, Categorical Between 18 and 65 years	10 Participants n=11 Participants
Age, Categorical >=65 years	1 Participants n=11 Participants
Sex: Female, Male Female	3 Participants n=11 Participants
Sex: Female, Male Male	8 Participants n=11 Participants
Region of Enrollment United States	11 Participants n=11 Participants
Amputation level Transfemoral	11 Participants n=11 Participants

PRIMARY outcome

Timeframe: After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

Satisfaction on ramp descent with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better.

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) Rheo Knee Users · worse	1 Participants
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) Rheo Knee Users · same	0 Participants
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) Rheo Knee Users · better	3 Participants
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) Hydraulic Users · worse	4 Participants
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) Hydraulic Users · same	1 Participants
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) Hydraulic Users · better	1 Participants

PRIMARY outcome

Timeframe: After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

Satisfaction on stair descent with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) In-house questionnaire Rheo Knee Users · worse	0 Participants
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) In-house questionnaire Rheo Knee Users · same	1 Participants
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) In-house questionnaire Rheo Knee Users · better	3 Participants
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) In-house questionnaire Hydraulic Users · worse	5 Participants
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) In-house questionnaire Hydraulic Users · same	0 Participants
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK) In-house questionnaire Hydraulic Users · better	1 Participants

PRIMARY outcome

Timeframe: After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

Satisfaction on level ground walking activity with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Satisfaction on Level Ground Walking Activity Rheo Knee users · Worse	0 Participants
Satisfaction on Level Ground Walking Activity Rheo Knee users · Same	4 Participants
Satisfaction on Level Ground Walking Activity Rheo Knee users · Better	0 Participants
Satisfaction on Level Ground Walking Activity Hydraulic users · Worse	0 Participants
Satisfaction on Level Ground Walking Activity Hydraulic users · Same	6 Participants
Satisfaction on Level Ground Walking Activity Hydraulic users · Better	0 Participants

PRIMARY outcome

Timeframe: Baseline and After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

The PEQ (Prosthesis Evaluation Questionnaire) assesses the quality of life and satisfaction for prosthetic users using a visual analog scale from 0 to 100, where higher scores indicate more positive responses. Only certain subsets were used, including the ambulation subscale, satisfaction and safety questions, and utility questions. The hypothesis tested was that the new MPK has a 95% chance of not negatively affecting overall satisfaction. If scores in Visit 2 (with the investigational device) were higher than in Visit 1 (with the prescribed device), it would support the hypothesis. The confidence interval bars represented in graph were visually compared to the margin of non-inferiority. No further statistical analysis was done.

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Change in Overall Satisfaction From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Hydraulic users	7.4 units on a scale Interval -9.1 to 23.8
Change in Overall Satisfaction From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use All users	5.5 units on a scale Interval -3.4 to 14.3
Change in Overall Satisfaction From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Rheo Knee users	2.6 units on a scale Interval -6.2 to 11.5

PRIMARY outcome

Timeframe: Baseline and After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

Average difference in distance walked in 2MWT with the new MPK compared to comparator (prescribed device) User walk for 2 minutes in their self selected walking speed on a 30 meter track.

The hypothesis being tested is that the new MPK has a 95% probability of not negatively affecting the distance walked on 2MWT.

For this hypothesis, if scores in visit 2 (subjects using the investigational device) were higher than in visit 1 (subjects using their prescribed device), the difference of Visit 2 - Visit 1 would be positive and would therefore support the corresponding hypothesis.

The confidence interval bars represented in graph were visually compared to the margin of non-inferiority. No further statistical analysis was done.

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Change in Distance Walked During 2-Minute Walk Test (2MWT) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Rheo Knee users	2.43 meters Interval -6.1 to 11.0
Change in Distance Walked During 2-Minute Walk Test (2MWT) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Hydraulic users	-1.8 meters Interval -6.1 to 2.4
Change in Distance Walked During 2-Minute Walk Test (2MWT) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use All users	-0.1 meters Interval -3.6 to 3.3

PRIMARY outcome

Timeframe: Baseline and After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

The TUG test is a simple evaluative test used to measure functional mobility and assess fall risk. Reduction in time (measured in seconds) to complete indicates improvement in mobility. Average time needed to perform the TUG with the new MPK compared to comparator (prescribed device). The hypothesis being tested is that the new MPK has a 95% probability of not negatively affecting the time needed to complete the TUG. For this hypothesis, if the completion times of the TUG during the Visit 2 (subjects using the investigational device) were lower than the ones in Visit 1 (subjects using their prescribed device), the difference of Visit 2 - Visit 1 would be negative and would therefore support the corresponding hypothesis. The confidence interval bars represented in graph were visually compared to the margin of non-inferiority. No further statistical analysis was done.

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Change in Time for the Timed Up and Go Test (TUG) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use All users	-0.2 time in seconds Interval -1.1 to 0.8
Change in Time for the Timed Up and Go Test (TUG) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Rheo Knee users	-0.1 time in seconds Interval -2.1 to 2.1
Change in Time for the Timed Up and Go Test (TUG) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Hydraulic users	-0.2 time in seconds Interval -1.7 to 1.3

PRIMARY outcome

Timeframe: Baseline and After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

Ability to ambulate over typical environmental obstacles is measured by the PLUS-M, using the T-score with the new MPK compared to the comparator (prescribed device). The PLUS-M is a self-report tool for assessing mobility in adults with lower limb amputation. The PLUS-M produces a T-score, which is standardized with a mean of 50 and a standard deviation of 10. Higher T-scores indicate greater mobility, with scores ranging from 17.5 to 76.6, based on responses to 44 questions. Only T-scores should be reported, as they are valid and comparable, unlike raw scores. The hypothesis being tested is that the new MPK has a 95% probability of not negatively affecting the PLUS-M score. If Visit 2 scores (using the investigational device) are higher than Visit 1 scores (using the prescribed device), the positive difference supports the hypothesis. The confidence interval bars represented in graph were visually compared to the margin of non-inferiority. No further statistical analysis was done.

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Change in T-score for the Prosthetic Limb Users Survey of Mobility (PLUS-M) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Rheo Knee users	3.8 T-score Interval -8.3 to 16.0
Change in T-score for the Prosthetic Limb Users Survey of Mobility (PLUS-M) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Hydraulic users	20.0 T-score Interval -18.4 to 58.3
Change in T-score for the Prosthetic Limb Users Survey of Mobility (PLUS-M) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use All users	13.5 T-score Interval -7.1 to 34.1

PRIMARY outcome

Timeframe: Baseline and After 4 weeks of use

Population: 4 subjects had magnetorheological working MPK, 6 subjects had a hydraulic one.

The ABC-scale is a 16-item questionnaire measuring confidence in performing ambulatory activities without falling, scored from 0 (no confidence) to 100 (full confidence). Cut-off scores define physical functioning: below 50% indicates low, 50-80% moderate, and above 80% high functioning. The hypothesis is that the new MPK has a 95% chance of not negatively impacting the ABC score. If Visit 2 scores (using the investigational device) exceed Visit 1 scores (using the prescribed device), it supports the hypothesis. Confidence interval bars in the graph were visually compared to the margin of non-inferiority, with no additional statistical analysis conducted.

Outcome measures

Measure	Exploratory Testing of a New Prosthetic Knee n=10 Participants New Microprocessor controlled prosthetic knee (MPK)
Change in Activities-Specific Balance Confidence Score (ABC) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Rheo Knee users	2.3 score on a scale Interval -14.8 to 19.5
Change in Activities-Specific Balance Confidence Score (ABC) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use Hydraulic users	5.4 score on a scale Interval -3.8 to 14.6
Change in Activities-Specific Balance Confidence Score (ABC) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use All users	4.1 score on a scale Interval -2.4 to 10.7

Adverse Events

Exploratory Testing of a New Prosthetic 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

Measure	Exploratory Testing of a New Prosthetic Knee n=11 participants at risk Navii Knee: Microprocessor controlled prosthetic knee (MPK)
Musculoskeletal and connective tissue disorders Unrelated issue on the residual limb	18.2% 2/11 • Number of events 2 • 4 weeks

Additional Information

Laurine Roussillon

Össur Iceland ehf.

Phone: +3548221812

Email: lroussillon@ossur.com

Results disclosure agreements

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