Clinical trial NCT06937242: Effects of Microprocessor-controlled Prosthetic Knees on Fall-related Health Outcomes in Limited Community Ambulators
Official title: Fall-related Health Outcome in Lower Limb Prosthesis Users: A Pragmatic Clinical Trial to Assess Effectiveness of Microprocessor-controlled Prosthetic Knees
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
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
Lead sponsor: Hanger Institute for Clinical Research and Education, LLC
Sponsor class: INDUSTRY
Collaborators: name: University of Washington
name: U.S. Army Medical Research Acquisition Activity
First posted: 2025-04-22
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: 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.
Primary purpose: SUPPORTIVE_CARE

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.

Detailed description: This study aims to assess the effects of microprocessor-controlled prosthetic knees on fall-related health outcomes in prosthesis users classified as limited community ambulators. This study also seeks to expand the existing research on the potential microprocessor-controlled prosthetic knees (MPKs) have on improving health outcomes for patients who are classified as limited community ambulators (i.e., Medicare Functional Level K2). The investigators will examine whether the anticipated reduction in falls in K2 users is accompanied by improvements in fall-related health outcomes like fall-related anxiety, fall-related self-efficacy, fall-related avoidance behaviors, fall-related interference, and fewer falls. Investigators will also examine whether MPK use in the K2 population leads to increased mobility, increased walking speed, and improvements in health-related quality of life.

A 12-month, pragmatic randomized control trial (pRCT) will be conducted to assess whether MPKs improve fall-related health outcomes in unilateral, transfemoral or knee disarticulation prosthesis users classified as limited community ambulators.

Patients will be invited to participate in the trial as a part of their routine prosthetic care. If a patient agrees to participate and is eligible, a follow-up appointment will be scheduled, and the patient will be consented by the research study team. Participants will then be randomized to the intervention or control group. Participants in the control arm of the trial will remain in their prescribed prosthesis with a non-microprocessor knee (nMPK). 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). The MPK provided to each participant in the intervention arm will be determined by the manufacturer's recommended patient-selection criteria. Transfemoral prosthesis users walking up to 0.83m/s (3km/hr) in the 2-minute walk test (2MWT) will receive a stance-only MPK (Kenevo), while participants walking more than 0.83m/s in the 2MWT will receive a stance-and-swing MPK (C-Leg 4). Study participants will wear the knee for 12 months.

Each participant will be assessed at baseline (after enrollment and randomization), and 1-, 3-, 6-, 9-, and 12-months after baseline. The baseline and 12-month assessments will be the primary study time points. T-scores on the Prosthetic Limb Users Survey of Fall-Related Health (PLUS-F) and number of fall events experienced over the prior year will serve as the primary endpoints. Participants will complete a selected set of performance-based tests and standardized self-report surveys. In addition to the outcome measures noted, investigators will collect sociodemographic, health, amputation, fall history, and prosthesis information by self-report in order to characterize study participants and assess the comparability of the study groups. Fall-related health outcomes (e.g. fall-related self-efficacy and fall-related interference) will be measured using new PLUS-F instruments as well as existing measures that measure fall-related outcomes. We will also co-administer the Prosthetic Limb Users Survey of Mobility (PLUS-M) to assess participants' prosthesis-related mobility. Walking speed, mobility, endurance, and quality of life will be measured. For the 6- and 12-month assessments, we will also collect the hours of wear and hours of activity in the prosthesis.

Participants in both groups will receive education and training specific to their prosthetic knee between assessment 1 (baseline) and assessment 2 (one-month follow-up). Training will consist of 1 to 4 sessions to facilitate participants' use of their assigned prostheses. The number of sessions will be determined by the ability of each participant to explain and/or perform specified tasks. A standardized protocol and training checklist will be developed by our team Physical Therapist specific to each condition in collaboration with the knees' manufacturer (Ottobock). Every 2 weeks, throughout the 12 months of patient participation, the number of falls and near-fall events, including the event, injury, treatment and/or hospitalization, and whether the falls occurred while wearing the prosthesis, will be collected.

Eligibility criteria: Inclusion Criteria:

* Unilateral transfemoral or knee disarticulation limb loss.
* 12 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:

  1. Houghton Score: 5-10
  2. Prosthetic Limb Users Survey of Mobility (PLUS-M) T-Score: if amputation etiology is vascular disease/diabetes \<49.45, otherwise, \<36.75.
  3. Amputee Mobility Predictor (AMPPRO) score: 27-42 collected within the last 24 months
* Ability to read, write, and understand English.

Exclusion Criteria:

* 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

Primary outcomes:
measure: Prosthetic Limb Users Survey of Fall-Related Self-Efficacy (PLUS-F-SEF)
timeFrame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
measure: Prosthetic Limb Users Survey of Fall-Related Anxiety (PLUS-F-ANX)
timeFrame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
measure: Prosthetic Limb Users Survey of Fall-Related Avoidance Behaviors (PLUS-F-AVB)
timeFrame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
measure: Prosthetic Limb Users Survey of Fall-Related Interference (PLUS-F-INT)
timeFrame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
measure: Number of Reported Falls and Near-Fall Events
timeFrame: Collected every two weeks starting at baseline up to 12 months
Secondary outcomes:
measure: EuroQol 5 Dimensions (EQ-5D)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
measure: Balance Recovery Scale (BRC)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
measure: Fear of Falling Avoidance Behaviors Questionnaire (FFABQ)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
measure: Prosthetic Limb Users Survey of Mobility (PLUS-M)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
measure: Timed Up and Go (TUG)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
measure: Ten Meter Walk Test (10mWT)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
measure: Two Minute Walk Test (2MWT)
timeFrame: Collected at baseline, 6-month, and 12-month assessments.
Other outcomes:
Locations:
city: Austin
country: United States
facility: Hanger Inc.
state: Texas
Study officials:
affiliation: Hanger Institute for Clinical Research and Education
name: Shane R. Wurdeman, PhD
role: PRINCIPAL_INVESTIGATOR
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