Clinical Outcomes With Non-Powered vs. Powered Prosthetic Knees by K2-level Amputees

NCT06194838 | Recruiting FDA Device

• 1 other identifier: 10877
• Study Type: interventional
• Target: 26
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this proposed project is to gather community-based data from the K2-level Transfemoral Amputee (TFA) population to aid in evidence-based prescription of powered prosthetic knees (i.e., choosing the right device to maximize the benefit for each patient). The investigators intend to use this trial data along with a concurrent study being conducted within the K3-K4 level population to guide the implementation of effective prescriptions towards those that can benefit most from a given device and limit prescription to those who would not see benefit in order to ensure the most judicious use of Department of Defense (DoD) and Veteran's Affairs healthcare dollars. The findings will also be shared with the research community to help drive the design of future devices by identifying what features and functions are most beneficial to which patient populations when the devices are used outside of the laboratory. In summary, more community-based data on how powered prosthetic knees compare with the current standard in TFA populations is needed to allow for improved clinical decision making and clinical outcomes.

Conditions

Amputation; Amputation; Traumatic, Leg, Lower; Limb; Absence, Congenital, Lower; Prosthesis User; Lower Limb Amputation Above Knee (Injury); Amputation; Traumatic, Leg: Thigh, Between Hip and Knee

Keywords

amputee; lower limb amputee; transfemoral amputee; prosthetic knee; power knee; mechanical knee; lower limb prosthesis user

Outcome Measures

Primary Outcomes (3)

• Step count

  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 during each 3 month intervention period. Similar to prior studies, the investigators will use the activity monitor to track the number of steps the subjects take in each condition. A higher step count is a better outcome.

  Monitored over entire study (9 months)

• Activities-Specific Balance Confidence scale (ABC) - Measuring change from baseline

  The ABC 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). A higher score means a better outcome. This survey will be given at the beginning and end of each study condition (3 conditions, 3 months per condition). Additionally, this survey will be given at the subject's last training session, which is dependent on the subject's scheduling availability and proficiency with each knee condition. The subject will have between 4-8 training sessions per condition until deemed proficient or the 8th session has been completed, whichever comes first. All training sessions are expected to be completed within the first month of each condition. This survey will be administered as a part of the master questionnaire.

  Throughout study completion, an average of 9 months

• Prosthesis Evaluation Questionnaire - Well Being (PEQ-WB) - Measuring change from baseline

  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 a higher score is a better outcome). This survey will be given at the beginning and end of each study condition (3 conditions, 3 months per condition). Additionally, this survey will be given at the subject's last training session, which is dependent on the subject's scheduling availability and proficiency with each knee condition. The subject will have between 4-8 training sessions per condition until deemed proficient or the 8th session has been completed, whichever comes first. All training sessions are expected to be completed within the first month of each condition. This survey will be administered as a part of the master questionnaire.

  Throughout study completion, an average of 9 months

Study Arms (3)

Comparator Baseline

NO INTERVENTION

The subject will wear the Ossur OFM-2, a passive mechanical knee which is the most commonly used knee for K2 users, for 3 months, as well as in the lab to complete outcome measures.

Ossur Power Knee

EXPERIMENTAL

The subject will wear the Ossur Power Knee for 3 months, as well as in the lab to complete outcome measures.

Device: Ossur Power Knee

Reboocon Intuy Knee

EXPERIMENTAL

The subject will wear the Reboocon Intuy Knee for 3 months, as well as in the lab to complete outcome measures.

Device: Reboocon Intuy Knee

Interventions

Ossur Power Knee DEVICE

Newest version of the commercially-available powered knee developed by Ossur.

Also known as: Ossur Power Knee III, PK3

Ossur Power Knee

Reboocon Intuy Knee DEVICE

Commercially-available powered knee developed by Reboocon.

Also known as: Intuy Knee

Reboocon Intuy Knee

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Are at least 18 years old
• Transfemoral prosthesis user (limb absence between the knee and hip)
• Current user of a mechanical knee
• Regularly wears prosthesis at least 5 days per week
• Have adequate clearance between distal end and ground for necessary knee and foot components
• Current Medicare Functional Classification Level (K-Level) of 2 as determined by the healthcare team
• Socket-Comfort Score: 6 or above to ensure adequate socket fit
• Six months or more experience on a prosthesis
• Body weight between 50kg and 116kg (110lbs - 256lbs)
• Height between 1.2m and 1.95m (47.2in and 76.8in)
• Has a phone to answer periodic study calls

You may not qualify if:

• Present injuries to residual limb or contralateral leg affecting functional ability
• Contralateral amputation proximal to MTP (metatarsophalangeal) joint
• Socket issues/changes in the last 6 weeks
• Users with bone-anchored implants
• Health or medical condition, diagnosis, or other cause that would prevent participant from effectively following study protocol, performing required outcome measures, and/or completing the study
• Subjects can be excluded at the discretion of the investigator for other unforeseen disqualifying criteria (such as specific cognitive issues, etc.).
• If subjects experience a health or medical condition that leaves them immobile for more than 2 weeks, they may be given the option to restart the study condition upon recovery, as long as eligibility criteria is still met, and comparable baseline functionality is demonstrated with outcomes measures.
• Using a knee that the subject is unfamiliar with may increase the risk of falling. Therefore, pregnant women should not participate in the study and will be screened by self-disclosure.

Sponsors & Collaborators

• Liberating Technologies, Inc.: lead
• Hanger Clinic: Prosthetics & Orthotics: collaborator

Study Sites (1)

Hanger Clinic

Austin, Texas, 78758, United States

RECRUITING

MeSH Terms

Conditions

Wounds and Injuries

Study Officials

• Jennifer Johansson, MS

  Liberating Technologies, Inc.

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Shane Wurdeman, PhD

CONTACT

402-290-8051; swurdeman@hanger.com

Jennifer Johansson, MS

CONTACT

774-233-0874; jen.johansson@liberatingtech.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: INDUSTRY
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: Participants will take home three interventional devices for data collection and feedback. One of the interventions will be the commercially available Ossur OFM-2, a passive mechanical knee, and the most commonly used knee for K2 users. The two other interventional devices will be commercially available powered knees: (1) the Ossur Power Knee and (2) the Reboocon Intuy Knee. Participants will be trained on the interventional knees during the first month of at-home use. Functional outcome measures and self-report surveys will also be completed in-lab before and after each take-home intervention, as well as at the last training visit, in order to form a detailed comparison between the three interventions.

Study Record Dates

• First Submitted: December 22, 2023
• First Posted: January 8, 2024
• Study Start: September 12, 2023
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): August 31, 2026
• Last Updated: September 3, 2025

Record last verified: 2025-09

Locations

US (1)