Functional Performance Evaluation of NU-FlexSIV Socket

Not Applicable

Completed

• Conditions: Artificial Limbs; Amputation
• Interventions: Device: Northwestern University Flexible Sub-Ischial Vacuum Socket; Device: Ischial Containment Socket

• Registration Number: NCT02678247
• Lead Sponsor: Northwestern University

Brief Summary

The overall objective of this study is to provide a more comfortable and functional prosthetic socket for persons with transfemoral amputation that will ultimately improve their quality of life.

Detailed Description

The proposed clinical trial will be an assessor-blinded prospective randomized cross-over trial wherein participants with unilateral transfemoral amputation will be randomized to using one of two socket conditions (i.e., sub-ischial or ischial containment) before crossing over to the other socket condition. Random allocation (computer-generated) utilizing blocks of random size will be used to assign the initial treatment condition. The trial will be balanced such that all subjects will receive all treatments (i.e., both socket conditions) and that all subjects will participate for the same number of periods (i.e., two). While a washout period is not strictly necessary, it is effectively included as subjects will need to transition back to their usual, pre-study socket/prosthesis while the second test socket is fabricated.

Allocation of intervention will be concealed from the investigators until after a subject is enrolled. The starting socket design will be enclosed in sequentially numbered, opaque, sealed envelopes. Envelopes will be opened sequentially and only after the participant's name and other details are written on the appropriate envelope.

Blinding of prosthetic interventions is challenging given that they are devices that must be custom-fabricated and donned each day by the subject. Hence, for this study only the assessor will be blinded. The blinded assessor will be responsible for administration of the clinical performance and patient-reported measures as well as processing of motion analysis data.

Study Timeline

• Study First Submitted: 2016-02-02
• Study First Submitted QC: 2016-02-04
• Study First Posted: 2016-02-09
• Study Start: 2016-04
• Primary Completion: 2019-12
• Study Completion: 2019-12
• Results First Submitted: 2020-12-28
• Results First Submitted QC: 2021-03-31
• Results First Posted: 2021-04-27
• Status Verified: 2021-05
• Last Update Submitted: 2021-05-25
• Last Update Posted: 2021-06-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• unilateral transfemoral amputation
• have used a prosthesis for two or more years
• have a residual limb that is stable in volume and free from wounds
• be physically fit enough to participate in the performance tests (Medicare Functional Classification Level K3 or K4)
• have no previous experience of the sub-ischial socket
• able to complete all visits for the duration of the protocol

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Exclusion Criteria

• have a residual limb femur of less than 5-inches
• co-morbidities that affect function, including neurologic abnormalities (e.g. neuropathic pain that would interfere with the study)
• do not speak and read English

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Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
NU-FlexSIV Socket	Ischial Containment Socket	The Northwestern University Flexible Sub-Ischial Vacuum Socket is a novel socket design for transfemoral amputees.
NU-FlexSIV Socket	Northwestern University Flexible Sub-Ischial Vacuum Socket	The Northwestern University Flexible Sub-Ischial Vacuum Socket is a novel socket design for transfemoral amputees.
IC Socket	Northwestern University Flexible Sub-Ischial Vacuum Socket	The Ischial Containment Socket is the standard of care socket design for transfemoral amputees.
IC Socket	Ischial Containment Socket	The Ischial Containment Socket is the standard of care socket design for transfemoral amputees.

Primary Outcome Measures

Name	Time	Method
Socket Comfort Score (SCS) Between IC Socket and NU-FlexSIV Sockets at 7 Weeks.	7 weeks	Socket comfort was assessed after each socket was worn for 7 weeks. SCS is an ordinal scale where the subject responds to the question, "On a 0 to 10 scale, if 0 represents the most uncomfortable socket fit you can imagine, and 10 represents the most comfortable socket fit, how would you score the comfort of the socket of your artificial limb at the moment?"

Secondary Outcome Measures

Name	Time	Method
Walking Speed Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	Walking speed was assessed after each socket was worn for 7 weeks. Participants walked along a 12 meter, level walkway at their normal self-selected speed. Marker based motion capture was used to assess walking speed (m/s).
Step Length Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	Step length was assessed after each socket was worn for 7 weeks. Participants walked along a 12 meter, level walkway at their normal self-selected speed. Marker based motion capture was used to assess step length (cm).
Hip Extension Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	Hip extension was assessed after each socket was worn for 7 weeks. Participants walked along a 12 meter, level walkway at their normal self-selected speed. Marker based motion capture was used to assess hip extension (degrees).
Hip Range of Motion Between the IC Socket and NU-FlexSIV Socket 7 Weeks.	7 weeks	Hip range of motion was assessed after each socket was worn for 7 weeks. Participants walked along a 12 meter, level walkway at their normal self-selected speed. Marker based motion capture was used to assess hip range of motion (degrees).
Trunk Motion Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	Trunk motion was assessed after each socket was worn for 7 weeks. Participants walked along a 12 meter, level walkway at their normal self-selected speed. Marker based motion capture was used to assess trunk motion (degrees).
Orthotics and Prosthetics Users' Survey (OPUS) Lower-Extremity Functional Status Measure Between the IC Socket and NU-FlexSIV Socket at 7 Weeks	7 weeks	Lower-Extremity Functional Status was assessed after each socket was worn for 7 weeks. The OPUS Lower-Extremity Functional Status measure is a self-report instrument that assesses functional status in persons who use orthoses and prostheses. It is comprised of 20 items rated on a 5-point rating scale. Responses to items are summed to produce a total score for the measure (0 to 80) with higher scores representing better functional status.
Orthotics andProsthetics Users' Survey (OPUS) Health Related Quality of Life Index Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	Health Related Quality of life was assessed after each socket was worn for 7 weeks. The OPUS Health Related Quality of Life measure is self-report instrument comprised of 23 items that are evaluated with a 5-point rating scale. Responses to items are summed to produce a total score for the index (0 to 92) with higher scores representing better quality of life.
Orthotics and Prosthetics Users' Survey (OPUS) Satisfaction With Device Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	Satisfaction with Device was assessed after each socket was worn for 7 weeks. The OPUS Satisfaction with Device measure is a set of 11 items rated on a 5-point rating scale. Responses to items are summed to produce a total score. 9 items were used in this study for a possible score of 9 to 45 with higher scores representing better satisfaction.
5-Times Rapid Sit-to-Stand Test (RSTS) Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	The 5-Times Rapid-Sit-to-Stand Test was assessed after each socket was worn for 7 weeks. Participants were asked to rise from a chair of standard height five times as fast as possible with their arms folded across their chests. Performance was timed.
Four-Square-Step Test (FSST) Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	The Four-Square-Step Test was assessed after each socket was worn for 7 weeks. Four sticks were placed flat on the floor in a cross that denoted a square. Participants were asked to complete a stepping sequence as fast as possible. Performance was timed.
T-Test of Agility (T-Test) Between the IC Socket and NU-FlexSIV Socket at 7 Weeks.	7 weeks	The T-Test was assessed after each socket was worn for 7 weeks. Four markers were set out so a "T" could be traced among them. The subject was asked to move as fast as possible between the markers, moving forwards, sideways and backwards. Performance was timed and reported in seconds.

Trial Locations

Locations (3)

Jesse Brown VA Medical Center Motion Analysis Research Laboratory; 🇺🇸 Chicago, Illinois, United States

Northwestern University Prosthetics-Orthotics Center; 🇺🇸 Chicago, Illinois, United States

Scheck and Siress Prosthetics Orthotics; 🇺🇸 Oakbrook Terrace, Illinois, United States