Clinical trial NCT02440711: Evaluation of a Modified Running-specific Prosthetic Foot
Official title: Endurance, Energy Expenditure, Perceived Function, and Satisfaction of Persons With Transtibial Limb Loss Using a Running-Specific Prosthesis Modified for Walking
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Transtibial Amputation
Lead sponsor: University of Washington
Sponsor class: OTHER
First posted: 2015-05-12
Enrollment: 36
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The goal of this study is to evaluate endurance, walking performance, mobility, and perceived exertion of transtibial prosthesis users (i.e., study participants) walking with a conventional energy storing prosthetic foot (ESF) and a novel modified running-specific prosthesis (mRSF). A randomized cross-over study will be conducted to determine if the mRSF provides superior performance to the ESF, which is commonly prescribed to most active individuals with lower limb amputation.

Detailed description: Amputation of a limb is a life-altering event with profound physical, psychological, and social implications. To address their functional, vocational, and recreational needs, people with lower limb amputation (LLA) are often provided with a prosthesis or artificial leg. While use of a prosthesis can allow an individual to achieve a basic level of functional mobility, absence of an anatomical foot and ankle still impairs their physical performance. As a result, people with LLA regularly exhibit decreased walking speeds, diminished endurance, and restricted ability to participate in desired life situations.

Over the past three decades, increasingly sophisticated prosthetic foot designs have been developed by the prosthetics industry to replace amputated structures in the leg. Contemporary, energy storing feet (ESF) employ advanced materials and unique geometric designs to improve walking performance and endurance of their users. Although prosthetic limbs with ESF allow people with LLA the potential to return to an active lifestyle, even the most advanced ESF do not significantly reduce the increased energy demands required for walking when compared to conventional prosthetic feet.

Commercially-available running-specific feet (RSF) like the Össur Cheetah (Össur, Reykjavik, Iceland) allow people with LLA to participate in athletic activities and sporting events. RSF provide significantly enhanced performance, compared to traditional ESF, by extending the length and increasing the stiffness of the prosthetic keel (forefoot). RSF also do not include a heel, as they are used only for running activities. Although transtibial runners with RSF exhibit endurance levels similar to non-amputees, the RSF design does not allow the biomechanical movements or provide the stability needed to use the foot for walking (over level or uneven terrain).

A novel modified running-specific foot (mRSF) has been developed to integrate the performance of a RSF with the utility of an ESF. The mRSF combines the running keel (forefoot) of a RSF with the walking heel of a ESF. The mRSF can then be used for walking, running, and other routine daily activities. Preliminary feedback on the mRSF suggests that users experience improved overall function and high satisfaction with the device. However, empirical evidence is needed to support prescription of this prosthetic foot at other clinical facilities.

The goal of this study is therefore to evaluate endurance, walking performance, mobility, and perceived exertion of transtibial prosthesis users (i.e., study participants) walking with a conventional ESF and the mRSF. Results will be compared to determine if the mRSF provides superior performance to the ESF, which is commonly prescribed to most active individuals with LLA.

Eligibility criteria: Inclusion Criteria:

* unilateral or bilateral, transtibial (below-knee) amputation from non-dysvascular causes
* Medicare functional classification level (K-level) 3 or higher (unlimited community ambulatory)
* prosthetic user for \> 1 year
* scheduled to receive a mRSF prosthesis
* able and willing to participate in the study protocol (e.g., treadmill walking, overground walking, respond to survey questions, able to read and write English)

Exclusion Criteria:

* contralateral lower or upper limb involvement
* any health condition that would limit participation in the study procedures (e.g., skin breakdown, heart disease)

Primary outcomes:
measure: Metabolic Oxygen Consumption (VO2), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Metabolic Oxygen Consumption (VO2), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Six-minute Walk Test (6MWT), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Six-minute Walk Test (6MWT), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Borg Rating of Perceived Exertion (CR100), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Borg Rating of Perceived Exertion (CR100), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Walking Speed, Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Walking Speed, Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Step Width, Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Step Width, Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Step Length, Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Step Length, Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Step Time, Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Step Time, Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
Secondary outcomes:
measure: Daily Step Activity, Participants With Unilateral Amputation
timeFrame: Participants' step count data from the 2 weeks prior to in-person testing.
measure: Daily Step Activity, Participants With Bilateral Amputation
timeFrame: Participants' step count data from the 2 weeks prior to in-person testing.
measure: Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Prosthetic Limb Users Survey of Mobility (PLUS-M), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Patient Reported Outcome Measurement Information System - Fatigue (PROMIS-Fatigue), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Activities-Specific Balance Confidence Scale (ABC), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Activities-Specific Balance Confidence Scale (ABC), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Unilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
measure: Trinity Amputation Prosthesis Experience Scales, Revised (TAPES-R), Participants With Bilateral Amputation
timeFrame: Participants were tested after using each foot in their prosthesis for 1 month.
Other outcomes:
Locations:
city: Seattle
country: United States
facility: University of Washington
state: Washington
Study officials:
affiliation: University of Washington
name: Brian Hafner, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Morgan SJ, McDonald CL, Halsne EG, Cheever SM, Salem R, Kramer PA, Hafner BJ. Laboratory- and community-based health outcomes in people with transtibial amputation using crossover and energy-storing prosthetic feet: A randomized crossover trial. PLoS One. 2018 Feb 7;13(2):e0189652. doi: 10.1371/journal.pone.0189652. eCollection 2018.