AmputationNCT06937242
Effects of Microprocessor-controlled Prosthetic Knees on Fall-related Health Outcomes in Limited Community Ambulators
A study testing Ottobock C-Leg 4 Microprocessor Knee and Ottobock Kenevo in people with Amputation and Prosthesis User, run by Hanger Institute for Clinical Research and Education, LLC at 1 site in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Amputation, Prosthesis User, Amputation; Traumatic, Leg: Thigh, Between Hip and Knee
- What is being tested?
- Ottobock C-Leg 4 Microprocessor Knee and Ottobock Kenevo
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteUnited States
- Study dates
- 11 Jul 2025to Feb 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Unilateral transfemoral or knee disarticulation limb loss.
- 6 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:
Show all 10Show fewer
- 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.
Who cannot join
- 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
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Hanger Inc.
Austin, Texas, 78758
Shane R. Wurdeman, PhD, 281-829-4746, swurdeman@hanger.com
Bretta L. Fystra, PhD, 512-994-6685, bfylstra@hanger.com
About this study
Official title: Fall-related Health Outcome in Lower Limb Prosthesis Users: A Pragmatic Clinical Trial to Assess Effectiveness of Microprocessor-controlled Prosthetic Knees
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.
Read the 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.
- 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
- Being tested
- Ottobock C-Leg 4 Microprocessor Knee, Ottobock Kenevo
- 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
- Medical subject headings
- Wounds and Injuries
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ottobock C-Leg 4 Microprocessor KneeDevice
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.
Ottobock KenevoDevice
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.
| Study group | Role | What they receive |
|---|---|---|
| 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. Receives: 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 |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: Collected every two weeks starting at baseline up to 12 months
Secondary outcomes (7)
EuroQol 5 Dimensions (EQ-5D)
The EQ-5D is a self-report measure of health-related quality of life (HRQL). The EQ-5D includes a descriptive component and a visual analog scale (VAS). The descriptive component evaluates respondents' HRQL in five areas (i.e., mobility, self-care, usual activities, pain/discomfort, and anxiety/depression) using a five- or three-level response option. We will use the five-level response option (EQ-5D-5L) for this study, where level 1 indicates "no problem" and level 5 indicates "unable to/extreme problems." The VAS component measures the respondent's HRQL on a 0 (the worst imaginable health) to 100 (the best imaginable health) VAS scale.
Measured: Collected at baseline, 6-month, and 12-month assessments.
Balance Recovery Scale (BRC)
The BRC is a 19-item self-report questionnaire designed to measure balance recovery self-efficacy (i.e., perceived reactive balance recovery). Respondents rate the degree of confidence with which they can recover from different losses of balance on a 10-point scale, from "cannot do at all" (0) to "highly certain can do" (10). A summary score is generated from the responses to questions in the BRC.
Measured: Collected at baseline, 6-month, and 12-month assessments.
Fear of Falling Avoidance Behaviors Questionnaire (FFABQ)
The FFABQ is a 14-item self-report instrument that measures the degree to which respondents avoid activities due to their fear of falling. Respondents rate the amount of times they avoid select activities due to their fear of falling on a 5-point scale from "always (100% of the time)" to "never (0% of the time)." A summary score is generated from the responses to questions in the FFABQ.
Measured: Collected at baseline, 6-month, and 12-month assessments.
Prosthetic Limb Users Survey of Mobility (PLUS-M)
The PLUS-M is a 12-item self-report instrument we developed in a prior study to measure mobility with an LLP. Respondents rate their perceived difficulty with performing various household and community activities on a 5-point scale, ranging from "without any difficulty" (5) to "unable to do" (1). A standardized T-score is generated for the PLUS-M using a lookup table that converts the raw score to a T-score.
Measured: Collected at baseline, 6-month, and 12-month assessments.
Timed Up and Go (TUG)
The TUG is a performance-based test designed to measure basic mobility tasks, such as sit-to-stand, gait initiation, walking, turning, and stand-to-sit. The TUG requires the participant stand up from a standard chair with arms, walk at a comfortable speed for 3 meters, turn around, and return to sit in the chair. The administrator times the participant as they perform the test. Lower TUG times are indicative of better performance (mobility). The TUG is scored as the lowest time achieved in one of two timed trials.
Measured: Collected at baseline, 6-month, and 12-month assessments.
Ten Meter Walk Test (10mWT)
The 10mWT is a performance-based test designed to measure a participant's self-selected walking speed. The 10mWT requires the participant to walk at a normal speed between lines taped on the floor. The administrator measures the time required to walk the middle six meters of the 10-meter distance. Lower times (ie, faster speed) is indicative of better performance. The 10mWT is scored by calculating the participant's walking speed in meters per second (m/s).
Measured: Collected at baseline, 6-month, and 12-month assessments.
Two Minute Walk Test (2MWT)
The 2MWT is a performance test designed to measure submaximal walking endurance. The 2MWT requires the participant to walk as far as possible over a period of 2 minutes. Longer distances indicate better performance (i.e., greater endurance). The administrator measures the distance the participant travels during the test. The 2MWT is scored as the total distance traveled in meters (m) over the test period.
Measured: Collected at baseline, 6-month, and 12-month assessments.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Apr 2025
- Study start11 Jul 2025
- Primary completionFeb 2027 (estimated)
- Study completionFeb 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (24)Papers the sponsor has linked to this study.
- Other trials for AmputationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- 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.
- Masking
- Double blind
- Who is masked
- Participant, Care provider
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Hanger Institute for Clinical Research and Education, LLC
- Sponsor type
- Industry (pharma, biotech, devices)
- Collaborators
- University of Washington, U.S. Army Medical Research Acquisition Activity
- Responsible party
- Sponsor
- Investigators
- Shane R. Wurdeman, PhD, Principal investigator, Hanger Institute for Clinical Research and Education
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06937242
- Sponsor's protocol ID
- UW-724
- Other IDs
- CDMRP-CDMRP Log OP190025
- Status last verified
- Feb 2026
- First submitted
- 11 Apr 2025
- Last updated
- 5 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Publications
Hu LY, Huang MW, Ke SW, Tsai CF. The distance function effect on k-nearest neighbor classification for medical datasets. Springerplus. 2016 Aug 9;5(1):1304. doi: 10.1186/s40064-016-2941-7. eCollection 2016.
PubMed 27547678Berry D. Microprocessor prosthetic knees. Phys Med Rehabil Clin N Am. 2006 Feb;17(1):91-113, vii. doi: 10.1016/j.pmr.2005.10.006.
PubMed 16517347Kim J, Shin W. How to do random allocation (randomization). Clin Orthop Surg. 2014 Mar;6(1):103-9. doi: 10.4055/cios.2014.6.1.103. Epub 2014 Feb 14.
PubMed 24605197Efird J. Blocked randomization with randomly selected block sizes. Int J Environ Res Public Health. 2011 Jan;8(1):15-20. doi: 10.3390/ijerph8010015. Epub 2010 Dec 23.
PubMed 21318011Eberly VJ, Mulroy SJ, Gronley JK, Perry J, Yule WJ, Burnfield JM. Impact of a stance phase microprocessor-controlled knee prosthesis on level walking in lower functioning individuals with a transfemoral amputation. Prosthet Orthot Int. 2014 Dec;38(6):447-55. doi: 10.1177/0309364613506912. Epub 2013 Oct 17.
PubMed 24135259Hafner BJ, Smith DG. Differences in function and safety between Medicare Functional Classification Level-2 and -3 transfemoral amputees and influence of prosthetic knee joint control. J Rehabil Res Dev. 2009;46(3):417-33.
PubMed 19675993Hafner BJ, Willingham LL, Buell NC, Allyn KJ, Smith DG. Evaluation of function, performance, and preference as transfemoral amputees transition from mechanical to microprocessor control of the prosthetic knee. Arch Phys Med Rehabil. 2007 Feb;88(2):207-17. doi: 10.1016/j.apmr.2006.10.030.
PubMed 17270519Jepson F, Datta D, Harris I, Heller B, Howitt J, McLean J. A comparative evaluation of the Adaptive knee and Catech knee joints: a preliminary study. Prosthet Orthot Int. 2008 Mar;32(1):84-92. doi: 10.1080/03093640701676376.
PubMed 18330807Kahle JT, Highsmith MJ, Hubbard SL. Comparison of nonmicroprocessor knee mechanism versus C-Leg on Prosthesis Evaluation Questionnaire, stumbles, falls, walking tests, stair descent, and knee preference. J Rehabil Res Dev. 2008;45(1):1-14. doi: 10.1682/jrrd.2007.04.0054.
PubMed 18566922Pauley T, Devlin M, Heslin K. Falls sustained during inpatient rehabilitation after lower limb amputation: prevalence and predictors. Am J Phys Med Rehabil. 2006 Jun;85(6):521-32; quiz, 533-5. doi: 10.1097/01.phm.0000219119.58965.8c.
PubMed 16715022Wong CK, Chihuri ST, Li G. Risk of fall-related injury in people with lower limb amputations: A prospective cohort study. J Rehabil Med. 2016 Jan;48(1):80-5. doi: 10.2340/16501977-2042.
PubMed 26694526Pezzin LE, Dillingham TR, MacKenzie EJ. Rehabilitation and the long-term outcomes of persons with trauma-related amputations. Arch Phys Med Rehabil. 2000 Mar;81(3):292-300. doi: 10.1016/s0003-9993(00)90074-1.
PubMed 10724073McWhinnie DL, Gordon AC, Collin J, Gray DW, Morrison JD. Rehabilitation outcome 5 years after 100 lower-limb amputations. Br J Surg. 1994 Nov;81(11):1596-9. doi: 10.1002/bjs.1800811110.
PubMed 7827880van Velzen JM, van Bennekom CA, Polomski W, Slootman JR, van der Woude LH, Houdijk H. Physical capacity and walking ability after lower limb amputation: a systematic review. Clin Rehabil. 2006 Nov;20(11):999-1016. doi: 10.1177/0269215506070700.
PubMed 17065543Wong CK, Rheinstein J, Stern MA. Benefits for Adults with Transfemoral Amputations and Peripheral Artery Disease Using Microprocessor Compared with Nonmicroprocessor Prosthetic Knees. Am J Phys Med Rehabil. 2015 Oct;94(10):804-10. doi: 10.1097/PHM.0000000000000265.
PubMed 25768067
Study at a glance
From the registry record, last updated by the sponsor on 5 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Fall-related Health Outcome in Lower Limb Prosthesis Users: A Pragmatic Clinical Trial to Assess Effectiveness of Microprocessor-controlled Prosthetic Knees
- ClinicalTrials.gov ID
- NCT06937242
- Acronym / sponsor ID
- UW-724
- 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
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Hanger Institute for Clinical Research and Education, LLCIndustry (pharma, biotech, devices)
- Collaborators
- University of Washington, U.S. Army Medical Research Acquisition Activity
- Study start
- 11 Jul 2025 (actual)
- Primary completion
- Feb 2027 (estimated)
- Study completion
- Feb 2027 (estimated)
- First posted
- 22 Apr 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, care provider)
- Number of arms
- 2
- 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.
| Arm | Type | Receives |
|---|---|---|
| MPK (Ottobock C-Leg 4 or Ottobock Kenevo) | Experimental | Device: Ottobock C-Leg 4 Microprocessor Knee, Device: Ottobock KenevoThe MPK provided to each participant in the intervention arm will be determined by the manufacturer's recommended patient-selection criteria. |
| nMPK | No intervention | –Participants in the control arm of the trial will remain in their prescribed non-microprocessor knee (nMPK) prosthesis |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (10 listed)
- Unilateral transfemoral or knee disarticulation limb loss.
- 6 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).
Key exclusion criteria (5 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Ottobock C-Leg 4 Microprocessor KneeSubjects 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. | Device | MPK (Ottobock C-Leg 4 or Ottobock Kenevo) |
| Ottobock KenevoSubjects 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. | Device | MPK (Ottobock C-Leg 4 or Ottobock Kenevo) |
Primary outcome
Prosthetic Limb Users Survey of Fall-Related Self-Efficacy (PLUS-F-SEF)
Time frame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
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.
Prosthetic Limb Users Survey of Fall-Related Anxiety (PLUS-F-ANX)
Time frame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
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.
Prosthetic Limb Users Survey of Fall-Related Avoidance Behaviors (PLUS-F-AVB)
Time frame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
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.
Prosthetic Limb Users Survey of Fall-Related Interference (PLUS-F-INT)
Time frame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.
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.
Number of Reported Falls and Near-Fall Events
Time frame: Collected every two weeks starting at baseline up to 12 months
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.
7 secondary outcomes
EuroQol 5 Dimensions (EQ-5D)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Balance Recovery Scale (BRC)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Fear of Falling Avoidance Behaviors Questionnaire (FFABQ)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Prosthetic Limb Users Survey of Mobility (PLUS-M)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Timed Up and Go (TUG)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Ten Meter Walk Test (10mWT)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Two Minute Walk Test (2MWT)
Time frame: Collected at baseline, 6-month, and 12-month assessments.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Feb 2026.
- Background: PubMed 27547678Hu LY, Huang MW, Ke SW, Tsai CF. The distance function effect on k-nearest neighbor classification for medical datasets. Springerplus. 2016 Aug 9;5(1):1304. doi: 10.1186/s40064-016-2941-7. eCollection 2016.
- Background: PubMed 16517347Berry D. Microprocessor prosthetic knees. Phys Med Rehabil Clin N Am. 2006 Feb;17(1):91-113, vii. doi: 10.1016/j.pmr.2005.10.006.
- Background: PubMed 24605197Kim J, Shin W. How to do random allocation (randomization). Clin Orthop Surg. 2014 Mar;6(1):103-9. doi: 10.4055/cios.2014.6.1.103. Epub 2014 Feb 14.
- Background: PubMed 21318011Efird J. Blocked randomization with randomly selected block sizes. Int J Environ Res Public Health. 2011 Jan;8(1):15-20. doi: 10.3390/ijerph8010015. Epub 2010 Dec 23.
- Background: PubMed 24135259Eberly VJ, Mulroy SJ, Gronley JK, Perry J, Yule WJ, Burnfield JM. Impact of a stance phase microprocessor-controlled knee prosthesis on level walking in lower functioning individuals with a transfemoral amputation. Prosthet Orthot Int. 2014 Dec;38(6):447-55. doi: 10.1177/0309364613506912. Epub 2013 Oct 17.
- Background: PubMed 19675993Hafner BJ, Smith DG. Differences in function and safety between Medicare Functional Classification Level-2 and -3 transfemoral amputees and influence of prosthetic knee joint control. J Rehabil Res Dev. 2009;46(3):417-33.
- Background: PubMed 17270519Hafner BJ, Willingham LL, Buell NC, Allyn KJ, Smith DG. Evaluation of function, performance, and preference as transfemoral amputees transition from mechanical to microprocessor control of the prosthetic knee. Arch Phys Med Rehabil. 2007 Feb;88(2):207-17. doi: 10.1016/j.apmr.2006.10.030.
- Background: PubMed 18330807Jepson F, Datta D, Harris I, Heller B, Howitt J, McLean J. A comparative evaluation of the Adaptive knee and Catech knee joints: a preliminary study. Prosthet Orthot Int. 2008 Mar;32(1):84-92. doi: 10.1080/03093640701676376.
- Background: PubMed 18566922Kahle JT, Highsmith MJ, Hubbard SL. Comparison of nonmicroprocessor knee mechanism versus C-Leg on Prosthesis Evaluation Questionnaire, stumbles, falls, walking tests, stair descent, and knee preference. J Rehabil Res Dev. 2008;45(1):1-14. doi: 10.1682/jrrd.2007.04.0054.
- Background: PubMed 16715022Pauley T, Devlin M, Heslin K. Falls sustained during inpatient rehabilitation after lower limb amputation: prevalence and predictors. Am J Phys Med Rehabil. 2006 Jun;85(6):521-32; quiz, 533-5. doi: 10.1097/01.phm.0000219119.58965.8c.
- Background: PubMed 26694526Wong CK, Chihuri ST, Li G. Risk of fall-related injury in people with lower limb amputations: A prospective cohort study. J Rehabil Med. 2016 Jan;48(1):80-5. doi: 10.2340/16501977-2042.
- Background: PubMed 10724073Pezzin LE, Dillingham TR, MacKenzie EJ. Rehabilitation and the long-term outcomes of persons with trauma-related amputations. Arch Phys Med Rehabil. 2000 Mar;81(3):292-300. doi: 10.1016/s0003-9993(00)90074-1.
- (CMS), U. S. C. f. M. m. S. Lower limb prosthetic workgroup consensus document (September 2017).Link provided by the sponsor.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Shane R. Wurdeman, PhD principal investigator
Hanger Institute for Clinical Research and Education
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Ottobock C-Leg 4 Microprocessor Knee and Ottobock Kenevo in people with Amputation and Prosthesis User, run by Hanger Institute for Clinical Research and Education, LLC at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 10 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 5 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Shane R. Wurdeman, PhD (281-829-4746, swurdeman@hanger.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Prosthetic Limb Users Survey of Fall-Related Self-Efficacy (PLUS-F-SEF) (time frame: Collected at baseline, 1-month, 3-month, 6-month, 9-month, and 12-month assessments.). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06937242, which also lists 24 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Feb 2026.