Clinical Investigation (Beta) of a New Developed Prosthetic Knee

Not Applicable

Completed

• Conditions: Amputation

• Registration Number: NCT06748729
• Lead Sponsor: Össur Iceland ehf

Brief Summary

The aim of this investigation is to evaluate the efficacy of the investigational device regarding performance improvements and satisfaction in descending activities for moderate to high active prosthesis users within the intended population for the investigational device. Additionally, the overall satisfaction for activities of daily living will be evaluated after a certain time of use (4 weeks home use).

Detailed Description

This investigation is a non-randomized single group repeated measures open label prospective design with observational and self-report measures.

Two scheduled study events are planned for amputee subjects, with 4 weeks between visits.

Study Timeline

• Study Start: 2024-02-26
• Primary Completion: 2024-03-28
• Study Completion: 2024-03-28
• Study First Submitted: 2024-04-17
• Study First Submitted QC: 2024-12-23
• Study First Posted: 2024-12-27
• Results First Submitted: 2025-03-07
• Status Verified: 2025-09
• Results First Submitted QC: 2025-09-01
• Last Update Submitted: 2025-09-01
• Results First Posted: 2025-09-04
• Last Update Posted: 2025-09-04

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 11

Inclusion Criteria

• 45Kg< body weight < 136Kg
• Cognitive ability to understand all instructions and questionnaires in the study;
• Unilateral TF/KD amputees that are regular prosthesis users for at least 3 months
• Current MPK users (passive MPKs only) regularly performing descent activities (stairs/ramps)
• Age ≥ 18 years
• Willing and able to participate in the study and follow the protocol

Exclusion Criteria

• Users with stump pain
• Users with socket problems
• Pregnant Users
• Users using Power Knee, Kenevo or mechanical knees as their prescribed prosthesis
• Alignment that cannot be matched with the Navii setup, as described in Instructions for use.
• Osseointegration

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
Satisfaction on Ramp Descent With the New Microprocessor-controlled Prosthetic Knee (MPK)	After 4 weeks of use	Satisfaction on ramp descent with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better.
Satisfaction on Stair Descent With the New Microprocessor-controlled Prosthetic Knee (MPK)	After 4 weeks of use	Satisfaction on stair descent with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better
Satisfaction on Level Ground Walking Activity	After 4 weeks of use	Satisfaction on level ground walking activity with the new MPK compared to prescribed device In-house questionnaire and Scale used: worse, same, better
Change in Overall Satisfaction From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use	Baseline and After 4 weeks of use	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.
Change in Distance Walked During 2-Minute Walk Test (2MWT) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use	Baseline and After 4 weeks of use	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.
Change in Time for the Timed Up and Go Test (TUG) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use	Baseline and After 4 weeks of use	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.
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	Baseline and After 4 weeks of use	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.
Change in Activities-Specific Balance Confidence Score (ABC) From Baseline With Prescribed Device to After 4 Weeks of Investigational Device Use	Baseline and After 4 weeks of use	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.

Trial Locations

Locations (1)

Össur Orlando; 🇺🇸 Orlando, Florida, United States