Use of Passive, Adaptive, and Active Prosthetic Knees in Persons With Unilateral, Transfemoral Amputation (OPK)

December 23, 2015 updated by: Brian Hafner, University of Washington

Outcomes Associated With Use of Passive, Adaptive, and Active Prosthetic Knees in Persons With Unilateral, Transfemoral Amputation: a Randomized Crossover Trial

The goals of this study are to assess measured, observed, and self-reported outcomes achieved through the use of passive (mechanical), active(motorized) and adaptive (magnetorheological) prosthetic knee control systems in individuals with unilateral, transfemoral amputation.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

An interrupted time-series trial with pre/post baseline assessments, randomized crossover of interventions, and within-phase repeated measures is used to evaluate and compare the effectiveness of the Össur Power Knee II and the Össur Rheo Knee in individuals with unilateral, transfemoral amputation. A rigorous and clinically-meaningful experimental protocol is applied to verify study participants receive appropriate training, experience, and assessment in each knee condition. A suite of standardized and ad-hoc physical performance tests, patient-reported questionnaires, and monitoring technologies were carefully selected to assess important, clinically-relevant participant outcomes. Comparative effectiveness of three prosthetic knee interventions are evaluated using direct measurement (i.e., timed tests), observed clinical ratings (i.e., subjective assessments of gait quality) and self-report instruments (i.e., health status surveys). Analyses will focus on identifying differences between control system technologies inherent to each type of prosthetic knee (i.e., passive [mechanical], adaptive [magnetorheological], and active [power]). Outcomes will be used to establish recommendations for which activities and patients knees are most appropriate or likely to produce a desired effect.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
12

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Washington
      • Seattle, Washington, United States, 98195
        • University of Washington

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

45 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • age 45 - 75
  • body weight less than 275lbs
  • unilateral amputation between the hip and knee
  • amputation due to non-vascular causes
  • no other major limb amputations
  • amputation occurred at least 2 years prior
  • stable limb volume (i.e., at least 6 months on an unmodified prosthetic socket)
  • intact skin tissue without open wounds or sores for at least 2 months
  • physiologically stable medical condition (i.e., non-degenerative)
  • possession and regular (i.e., daily) use of a prosthesis with a prosthetic knee with non-microprocessor (i.e., mechanical or fluid) stance control
  • Medicare functional classification level (MFCL or "K-level") 3

Exclusion Criteria:

  • expect to receive or are expected to require a replacement prosthetic socket within 15 months
  • complete reliance on an assistive device (i.e., cane or walker) for ambulation

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Prosthetic knee
Subjects crossed over between interventions (three different prosthetic knees). Knee conditions include 1) Active knee (Ossur Power Knee II); 2) Adaptive knee (Ossur Rheo); and 3) Passive knee (Various manufacturers)
Device: Active knee (Ossur Power Knee II)
Prosthetic knee with active control system.
Other Names:
  • Power knee
  • Motorized knee
Device: Adaptive knee (Ossur Rheo)
Prosthetic knee with adaptive control system.
Other Names:
  • Magnetorheological knee
  • Microprocessor knee
Device: Passive knee (Various manufacturers)
Prosthetic knee with mechanical control system.
Other Names:
  • Mechanical knee
  • Hydraulic knee
  • Pneumatic knee

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Timed Up and Go
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Timed performance test that measures rising from a chair, walking 3m, and returning to a seated position.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Timed Ramp Test
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Timed performance test that involves walking up and down a 14ft ramp.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Timed Stair Test
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Timed performance test that involves walking up and down 6 steps.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Step activity
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Average daily step counts measured by an accelerometer-based device.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Obstacle course time
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Time to walk a 1/2-mile outdoor walking course.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Reported Falls
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Self-report phone survey.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Prosthesis Evaluation Questionnaire (PEQ)
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Self-report computerized survey (12 questions)
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Activities Specific Balance Confidence Scale (ABC)
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Self-report computerized survey (18 questions).
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Patient Reported Outcomes Measurement Information System (PROMIS)
Time Frame: Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)
Self-report computerized questionnaire with 8-14 questions per domain. Includes Physical Function, Fatigue, and General Health subdomains.
Change from Baseline (mean score at weeks 1, 2, 3, and 4) to Follow-Up (mean score at weeks 8, 12, 16, 20, 24, and 28)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Washington

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Össur Ehf

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Brian Hafner, PhD, University of Washington

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 1, 2011

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
September 1, 2013

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
September 1, 2013

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
July 29, 2014

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 14, 2014

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 18, 2014

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
December 28, 2015

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 23, 2015

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
December 1, 2015

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 40660-A
  • A62089 (Other Identifier: University of Washington)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings