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

University of Washington

Status: Completed

Conditions: Transfemoral Amputation

Treatments: Device: Active knee (Ossur Power Knee II); Device: Passive knee (Various manufacturers); Device: Adaptive knee (Ossur Rheo)

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT02219230

40660-A

A62089 (Other Identifier)

Details and patient eligibility

About

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.

Full 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.

Enrollment: 12 patients

Sex: All

Ages: 45 to 75 years old

Volunteers: No Healthy Volunteers

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

Trial design

12 participants in 1 patient group

Prosthetic knee

Experimental group

Description:

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)

Treatment:

Device: Adaptive knee (Ossur Rheo)

Device: Passive knee (Various manufacturers)

Device: Active knee (Ossur Power Knee II)