Effect of a Microprocessor-controlled Prosthetic Knee Joint on K2 Level Ambulators

NCT07103798 | Not Yet Recruiting

• 2 other identifiers: RRD2-005-24WRX005610
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 2

Brief Summary

Microprocessor-controlled knees (MPKs) automatically adjust resistance or damping in the joint to improve swing- and/or stance-phase control as appropriate for the prosthesis user during gait. The purpose of this proposed investigation is to determine if there are substantial physical and psychological benefits to fitting lower functioning Veteran ambulators having transfemoral amputations with an MPK compared with a nonmicroprocessor-controlled knee (NMPK). Using a repeated-measures, cross-sectional experimental design, approximately 20 Veterans with unilateral, transfemoral amputations will be evaluated on two separate occasions at the Jesse Brown VA Medical Center or the Edward Hines, Jr. VA Hospital, first with their conventional NMPK and then again after a 2-month accommodation period with the College Park Icon MPK.

Conditions

Transfemoral Amputation; Limb Loss; Limb Absence

Keywords

amputation; limb loss; limb deficiency; transfemoral; above-knee; prosthesis; knee joint

Outcome Measures

Primary Outcomes (4)

• Walking speed

  Walking speed will be measured as participants walk on level ground at slow, normal and fast speeds.

  To be measured before and immediately following the 2-month accommodation period of wearing the MPK.

• Falls during walking

  The number of falls that occur while the subject is walking will be recorded in a daily diary.

  To be determined before and during the 2-month accommodation period of wearing the MPK

• PLUS-M

  The Prosthetic Limb User Survey of Mobility (PLUS-M) will be used to determine the mobility of subjects before and after fitting with the MPK. Scores range from 12-60 points, and a higher score indicates greater mobility.

  To be measured before and immediately following the 2-month accommodation period of wearing the MPK.

• Prosthetic Knee Preference

  Subjects will be asked which prosthetic knee they prefer at the completion of the study. For those that indicate preference for the MPK, they will be permitted to keep it in their prosthesis. For those that prefer the NMPK, their prosthesis will be restored to the configuration prior to beginning the study.

  To be asked immediately following the 2-month accommodation period of wearing the MPK.

Secondary Outcomes (2)

• ABC Scale

  To be administered before and immediately following the 2-month accommodation period of wearing the MPK.

• OPUS

  To be administered before and immediately following the 2-month accommodation period of wearing the MPK.

Study Arms (2)

MPK

EXPERIMENTAL

Subjects will be fitted with the College Park ICON MPK and permitted to accommodate for 2 months prior to data collection.

Other: College Park ICON

NMPK

ACTIVE COMPARATOR

Subjects will initially be evaluated walking on their conventional NMPK as a baseline prior to being fitted with the MPK.

Other: Conventional NMPK

Interventions

College Park ICON OTHER

Subjects will be fitted and trained on the College Park ICON MPK. An accommodation period of 2 months will be provided prior to evaluation with the knee joint.

MPK

Conventional NMPK OTHER

Subjects will be tested walking with their conventional, mechanical prosthetic knee prior to being fitted with the MPK.

NMPK

Eligibility Criteria

• Age: 45 Years - 85 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Unilateral, transfemoral amputation (any etiology).
• Age from 45-85 years.
• Residual limb length classified as standard (i.e., medium) to long.
• Prosthesis user for at least 1 year prior to enrolling in the study.
• K2-level classification while using their NMPK.
• Good sensation on their residual limb.
• Good skin integrity upon visual inspection.
• Presents with good socket fit based upon a standard assessment by the study prosthetist.

You may not qualify if:

• Bilateral leg amputations.
• Individuals with a knee disarticulation.

Sponsors & Collaborators

• VA Office of Research and Development: lead

Study Sites (2)

Jesse Brown VA Medical Center, Chicago, IL

Chicago, Illinois, 60612, United States

Location

Edward Hines Jr. VA Hospital, Hines, IL

Hines, Illinois, 60141-3030, United States

Location

Study Officials

• Steven A Gard, PhD

  Jesse Brown VA Medical Center, Chicago, IL

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Rebecca Stine, MS

CONTACT

(312) 503-5726; rebecca.stine@va.gov

Steven A Gard, PhD

CONTACT

(312) 503-5718; steven.gard@va.gov

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: SPONSOR

Model Details: Using a cross-sectional experimental design, approximately 20 Veterans who are low functioning ambulators with unilateral, transfemoral amputations will be evaluated on two separate occasions at the Jesse Brown VA Medical Center or the Edward Hines, Jr. VA Hospital, first with their conventional NMPK and then again after a two-month accommodation period with the College Park Icon MPK.

Study Record Dates

• First Submitted: July 15, 2025
• First Posted: August 5, 2025
• Study Start: May 1, 2026
• Primary Completion (Estimated): March 1, 2028
• Study Completion (Estimated): April 30, 2028
• Last Updated: March 19, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (2)