Effects of Microprocessor-controlled Prosthetic Knees on Fall-related Health Outcomes in Limited Community Ambulators

NCT06937242 | Recruiting FDA Device

• 2 other identifiers: UW-724CDMRP-CDMRP Log OP190025
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this study is to find out if using microprocessor-controlled prosthetic knees (MPKs), prosthetic knees with a built-in computer, improves health outcomes related to falls in adults who use above-knee prostheses. The main questions are:

• Do individuals with MPKs have fewer fall-related health issues compared to those with non-microprocessor-controlled prosthetic knees (nMPKs)?
• Do individuals with MPKs have increased mobility, faster walking speed, and improved quality of life compared to those with nMPKs? Participants who have recently received an nMPK as part of their regular care can join the study. Those randomized to the control group will keep using their nMPK, while those randomized to the intervention group will receive a stance-and-swing MPK or a stance-only MPK.

Conditions

Amputation; Prosthesis User; Amputation; Traumatic, Leg: Thigh, Between Hip and Knee; Limb; Absence, Congenital, Lower; Lower Limb Amputation Above Knee (Injury); Lower Limb Amputation Above Knee

Keywords

amputation; lower limb amputation; lower limb prosthesis user; mechanical knee; microprocessor knee; transfemoral amputation; knee disarticulation; prosthetic knee; falls; falling; amputee; transfemoral amputee; MPK

Outcome Measures

Primary Outcomes (5)

• Prosthetic Limb Users Survey of Fall-Related Self-Efficacy (PLUS-F-SEF)

  The PLUS-F-SEF is a 15-item self-report instrument we developed in the present study to measure perceived ability to avoid a loss of balance while performing an activity. Respondents rate their degree of confidence on a 5-point scale from "not at all confident" (1) to "very much confident" (5). A standardized T-score is generated for the PLUS-F-SEF using a lookup table that converts the raw score to a T-score.

  Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.

• Prosthetic Limb Users Survey of Fall-Related Anxiety (PLUS-F-ANX)

  The PLUS-F-ANX is a 15-item self-report instrument we developed in the present study to measure perceived apprehensions or concerns about losing one's balance or falling. Respondents rate the frequency with which they experience various emotional responses on a 5-point scale from "never" (1) to "always" (5). A standardized T-score is generated for the PLUS-F-ANX using a lookup table that converts the raw score to a T-score.

  Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.

• Prosthetic Limb Users Survey of Fall-Related Avoidance Behaviors (PLUS-F-AVB)

  The PLUS-F-AVB is a 15-item self-report instrument we developed in the present study to measure perceived changes in the manner or frequency with which activities are performed to avoid losing one's balance or falling. Respondents rate the frequency with which they make changes on a 5-point scale from "never" (1) to "always" (5). A standardized T-score is generated for the PLUS-F-AVB using a lookup table that converts the raw score to a T-score.

  Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.

• Prosthetic Limb Users Survey of Fall-Related Interference (PLUS-F-INT)

  The PLUS-F-INT is a 15-item self-report instrument we developed in the present study to measure perceived restrictions in social, cognitive, emotional, and/or physical life situations due to risk of falls. Respondents rate the amount of interference on a 5-point scale from "not at all" (1) to "very much" (5). A standardized T-score is generated for the PLUS-F-INT using a lookup table that converts the raw score to a T-score.

  Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.

• Number of Reported Falls and Near-Fall Events

  Participants will be contacted every 2 weeks starting at baseline through study completion to determine whether they experienced a fall event (either a fall or near-fall). For each event experienced, participants will be asked to report the details of that event using the Lower Limb Prosthesis User Fall Event Survey we developed in a prior study. This instrument asks respondents to report the activity, surroundings, situation, mechanics, and consequences of each event. Fall events will be scored as the total number of falls, near-falls, and all fall events experienced. The details of the events are descriptive in nature and will be used to characterize the falls experienced by the participant.

  Collected every two weeks starting at baseline up to 12 months

Secondary Outcomes (7)

• EuroQol 5 Dimensions (EQ-5D)

  Collected at baseline, 6-month, and 12-month assessments.

• Balance Recovery Scale (BRC)

  Collected at baseline, 6-month, and 12-month assessments.

• Fear of Falling Avoidance Behaviors Questionnaire (FFABQ)

  Collected at baseline, 6-month, and 12-month assessments.

• Prosthetic Limb Users Survey of Mobility (PLUS-M)

  Collected at baseline, 6-month, and 12-month assessments.

• Timed Up and Go (TUG)

  Collected at baseline, 6-month, and 12-month assessments.

Study Arms (2)

MPK (Ottobock C-Leg 4 or Ottobock Kenevo)

EXPERIMENTAL

The MPK provided to each participant in the intervention arm will be determined by the manufacturer's recommended patient-selection criteria.

Device: Ottobock C-Leg 4 Microprocessor Knee; Device: Ottobock Kenevo

nMPK

NO INTERVENTION

Participants in the control arm of the trial will remain in their prescribed non-microprocessor knee (nMPK) prosthesis

Interventions

Ottobock C-Leg 4 Microprocessor Knee DEVICE

Subjects in the intervention group who can walk more than 0.83m/s in the 2-minute walk test (2MWT) will receive the Ottobock C-Leg 4, a stance-and-swing microprocessor knee.

MPK (Ottobock C-Leg 4 or Ottobock Kenevo)

Ottobock Kenevo DEVICE

Subjects in the intervention group who can walk up to 0.83m/s (3km/hr) in the 2-minute walk test (2MWT) will receive the Kenevo, a stance-only microprocessor knee.

MPK (Ottobock C-Leg 4 or Ottobock Kenevo)

Eligibility Criteria

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

You may qualify if:

• Unilateral transfemoral or knee disarticulation limb loss.
• months or longer since time of limb loss.
• Current user of a prosthesis with a non-microprocessor-controlled prosthetic knee.
• Received a replacement prosthesis with a non-microprocessor knee in the past 4-24 months.
• Clinician has deemed patient limited community ambulator (Medicare functional classification level K2).
• In addition, Medicare functional classification level K2 as determined by at least one of the following criteria:
• Houghton Score: 5-10
• Prosthetic Limb Users Survey of Mobility (PLUS-M) T-Score: if amputation etiology is vascular disease/diabetes \<49.45, otherwise, \<36.75.
• Amputee Mobility Predictor (AMPPRO) score: 27-42 collected within the last 24 months
• Ability to read, write, and understand English.

You may not qualify if:

• Any health condition that would prevent safely completing trial activities.
• Any individuals that weigh 275 lbs or more.
• Any individuals who wear their prosthesis less than 3 days a week or less than a total of 24 hours a week
• Individuals with a history of acute or chronic residual limb breakdown
• Individuals with declining health status such that he/she subsequently reports reduced activity over the past 6 months

Sponsors & Collaborators

• University of Washington: collaborator
• U.S. Army Medical Research Acquisition Activity: collaborator
• Hanger Institute for Clinical Research and Education, LLC: lead

Study Sites (1)

Hanger Inc.

Austin, Texas, 78758, United States

RECRUITING

Related Publications (24)

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Related Links

• (CMS), U. S. C. f. M. m. S. Lower limb prosthetic workgroup consensus document (September 2017).

MeSH Terms

Conditions

Wounds and Injuries

Study Officials

• Shane R. Wurdeman, PhD

  Hanger Institute for Clinical Research and Education

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Shane R. Wurdeman, PhD

CONTACT

281-829-4746; swurdeman@hanger.com

Bretta L. Fylstra, PhD

CONTACT

512-994-6685; bfylstra@hanger.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, CARE PROVIDER
• Masking Details: The randomization plan will be hidden from investigators responsible for enrolling and consenting study participants. The prosthetist and participant will be unblinded to assignment following enrollment. It is not feasible to blind participants throughout the study due to key differences in the intervention and control devices (e.g., the MPK requires daily charging, but the NMPK does not).
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Participants will be randomized to the intervention or control group. Participants randomized to the intervention arm of the trial will have their nMPK exchanged for either a stance-and-swing MPK (Ottobock C-Leg 4) or a stance-only MPK (Ottobock Kenevo). Participants in the control arm of the trial will remain in their prescribed prosthesis with a nMPK.

Study Record Dates

• First Submitted: April 11, 2025
• First Posted: April 22, 2025
• Study Start: July 11, 2025
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): February 1, 2027
• Last Updated: February 5, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)