Amputation of Lower Limb Above KneeBAMNCT07613502
Bio Leg: Advancing Mobility (BAM)
A study testing Bio Leg in people with Amputation of Lower Limb Above Knee and Amputee, run by University of Florida at 1 site in United States.
Trial summary
Following transfemoral amputation, regaining functional mobility, particularly the ability to navigate curbs, ramps, long distances, and the ability to stand is challenging and often unattainable. Use of advanced prosthetic limb technology can dramatically influence mobility outcomes. Read more about this study
- Who is it for?
- Ages 40 to 80 years
- Conditions the study is for
- Amputation of Lower Limb Above Knee, Amputee, Amputation
- What is being tested?
- Bio Leg
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 12 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Jun 2026to Jul 2028
- 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 40 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults 40 to 80 years of age
- Unilateral transfemoral amputation > 1 year
- K3 or K4 ambulator (based on the K classification system) and able to walk with no greater assistances than a single point cane
- Current microprocessor-controlled prosthesis (C-leg) user with > 6 months experience and able to walk without a device of using a single point cane
- Able to give informed consent
Who cannot join
- Severe cardiovascular condition or other disease limiting study participation
- Skin lesions or wounds, acute or unstable fracture, diagnosis of osteoarthritis or bone impairments affecting safe participation in walking activities
- Residual limb dysfunction (i.e. joint contracture) limiting mobility or study participation
- Pain that limits walking of participation in walking activities
- Current participation in rehabilitation to address walking function
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
Brooks Rehabilitation
Jacksonville, Florida, 32216
About this study
Official title: Adaptive Mobility Technology: A Comparative Study of C-Leg and Bio Leg
Following transfemoral amputation, regaining functional mobility, particularly the ability to navigate curbs, ramps, long distances, and the ability to stand is challenging and often unattainable. Use of advanced prosthetic limb technology can dramatically influence mobility outcomes. The purpose of this study is to compare walking function in individuals with transfemoral amputations who are current users of the C-leg (micro-processor controlled prosthetic knee; current clinical standard) to function achieved when using the Bio Leg powered micro-processor prosthetic knee.
Read the detailed description
Although microprocessor-controlled knees (MPK) such as the C-Leg have demonstrated clear benefits over non-microprocessor-controlled prosthetic knees, it remains unclear whether powered knee assistance provides additional advantages in movement quality, metabolic efficiency, and limb loading during walking adaptability tasks.
This study directly addresses this gap by comparing mobility using the Bio Leg to mobility with the C-Leg using outcome measures that reflect real-world mobility challenges.
By generating objective evidence on whether powered knee assistance improves biomechanics, efficiency, and stability beyond that achieved with an established MPK, this study will inform prosthetic prescription, rehabilitation strategies, and payer decision-making. Given the growing population of individuals living with transfemoral amputation, identifying technologies that support safe, efficient, and confident mobility has important implications for community participation, long-term musculoskeletal health, and quality of life.
This study uses a within-subject repeated-measures design in which each participant is assessed under two conditions: current prosthesis and the Bio Leg prosthesis. All primary and secondary outcomes will be analyzed as within-participant differences, with each participant serving as their own control.
- Conditions
- Amputation of Lower Limb Above Knee, Amputee, Amputation
- Being tested
- Bio Leg
- Keywords
- Amputation, Above Knee Amputation, AKA, Prosthetic Use, Prostheses, C-leg, BioLeg, Amputee
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Bio LegDevice
After completing biomechanics and clinical testing at Pre Assessment with their C-Leg, participants will be fitted with a Bio-Leg prosthesis at the prosthetist clinic. The participant will train and use the Bio-Leg prosthesis during a 4-6 week acclimation period. The participant will then complete the same biomechanics and clinical testing at Post Assessment.
| Study group | Role | What they receive |
|---|---|---|
| C-Leg | No intervention | The first assessment will involve testing the participant with their current C-leg microprocessor prosthesis. |
| Bio Leg | Experimental | After the Bio Leg fitting, the participant will exclusively wear the Bio Leg knee component for an acclimation period that will be a minimum of 4 weeks and up to 6 depending on participant's schedule and comfort/ease of using the device. Each participant will complete a minimum of 2 and up to 4 physical therapy sessions during the acclimation period. These physical therapy sessions will involve standard physical therapy training for use of a prosthetic limb after amputation. Following the acclimation period, the participant will complete the second assessment, which will mirror the first assessment. Receives: Device: Bio Leg |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in 6-Minute Walk Test (6MWT)
The distance that a patient should walk based on their height, weight, age, and gender. Performance assessment of walking endurance for 6 minutes. An increase in the number of meters walked during this assessment reflects an improvement in walking endurance.
Measured: Baseline, 4-6 weeks
Change in Interlimb Symmetry (Ground Reaction Forces)
A direct measure of vertical ground reaction forces during the rising phase of a sit-to-stand task (measured in Newtons) using standard force plates embedded in the floor. Increased symmetry in ground reaction forces between the lower limbs reflects improved equalization of weight distribution between the limbs.
Measured: Baseline, 4-6 weeks
Change in Metabolic Efficiency (O2/kg/m)
A direct measure assessed during the six-minute walk test. Metabolic efficiency is determined by the energy cost of transport, defined as oxygen consumption per unit body weight and distance walked (O₂/kg/m), which accounts for the individual's weight and walking speed. Improved metabolic efficiency reflects enhanced oxygen delivery and utilization during walking.
Measured: Baseline, 4-6 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 May 2026
- Study start1 Jun 2026
- Primary completionJul 2027 (estimated)
- Study completionJul 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Amputation of Lower Limb Above KneeStudies of the same condition, open and under way.
- More trials run by University of FloridaThe sponsor's other registered studies.
- 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
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Crossover
- Model description
- Within-subject crossover design
- Masking
- None (open label)
- Enrolment
- 12 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Florida
- Sponsor type
- University, hospital or other
- Collaborators
- Brooks Rehabilitation
- Responsible party
- Sponsor
- Investigators
- Emily J Fox, PT, DPT, MHS, PhD, Principal investigator, University of Florida & Brooks Rehabilitation
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07613502
- Sponsor's protocol ID
- IRB202600203
- Acronym
- BAM
- Status last verified
- May 2026
- First submitted
- 21 May 2026
- Last updated
- 26 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 26 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Adaptive Mobility Technology: A Comparative Study of C-Leg and Bio Leg
- ClinicalTrials.gov ID
- NCT07613502
- Acronym / sponsor ID
- BAM / IRB202600203
- Conditions
- Amputation of Lower Limb Above Knee, Amputee, Amputation
- Keywords
- Amputation, Above Knee Amputation, AKA, Prosthetic Use, Prostheses, C-leg, BioLeg, Amputee
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 12 participants (estimated)
- Lead sponsor
- University of FloridaUniversity, hospital or other
- Collaborators
- Brooks Rehabilitation
- Study start
- 1 Jun 2026 (actual)
- Primary completion
- Jul 2027 (estimated)
- Study completion
- Jul 2028 (estimated)
- First posted
- 29 May 2026 (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.
Following transfemoral amputation, regaining functional mobility, particularly the ability to navigate curbs, ramps, long distances, and the ability to stand is challenging and often unattainable. Use of advanced prosthetic limb technology can dramatically influence mobility outcomes. The purpose of this study is to compare walking function in individuals with transfemoral amputations who are current users of the C-leg (micro-processor controlled prosthetic knee; current clinical standard) to function achieved when using the Bio Leg powered micro-processor prosthetic knee.
Detailed description
Although microprocessor-controlled knees (MPK) such as the C-Leg have demonstrated clear benefits over non-microprocessor-controlled prosthetic knees, it remains unclear whether powered knee assistance provides additional advantages in movement quality, metabolic efficiency, and limb loading during walking adaptability tasks.
This study directly addresses this gap by comparing mobility using the Bio Leg to mobility with the C-Leg using outcome measures that reflect real-world mobility challenges.
By generating objective evidence on whether powered knee assistance improves biomechanics, efficiency, and stability beyond that achieved with an established MPK, this study will inform prosthetic prescription, rehabilitation strategies, and payer decision-making. Given the growing population of individuals living with transfemoral amputation, identifying technologies that support safe, efficient, and confident mobility has important implications for community participation, long-term musculoskeletal health, and quality of life.
This study uses a within-subject repeated-measures design in which each participant is assessed under two conditions: current prosthesis and the Bio Leg prosthesis. All primary and secondary outcomes will be analyzed as within-participant differences, with each participant serving as their own control.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Within-subject crossover design
| Arm | Type | Receives |
|---|---|---|
| C-Leg | No intervention | –The first assessment will involve testing the participant with their current C-leg microprocessor prosthesis. |
| Bio Leg | Experimental | Device: Bio LegAfter the Bio Leg fitting, the participant will exclusively wear the Bio Leg knee component for an acclimation period that will be a minimum of 4 weeks and up to 6 depending on participant's schedule and comfort/ease of using the device. Each participant will complete a minimum of 2 and up to 4 physical therapy sessions during the acclimation period. These physical therapy sessions will involve standard physical therapy training for use of a prosthetic limb after amputation. Following the acclimation period, the participant will complete the second assessment, which will mirror the first assessment. |
Who may qualify
- Ages
- 40 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Adults 40 to 80 years of age
- Unilateral transfemoral amputation > 1 year
- K3 or K4 ambulator (based on the K classification system) and able to walk with no greater assistances than a single point cane
- Current microprocessor-controlled prosthesis (C-leg) user with > 6 months experience and able to walk without a device of using a single point cane
- Able to give informed consent
Key exclusion criteria (5 listed)
- Severe cardiovascular condition or other disease limiting study participation
- Skin lesions or wounds, acute or unstable fracture, diagnosis of osteoarthritis or bone impairments affecting safe participation in walking activities
- Residual limb dysfunction (i.e. joint contracture) limiting mobility or study participation
- Pain that limits walking of participation in walking activities
- Current participation in rehabilitation to address walking function
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 |
|---|---|---|
| Bio LegAfter completing biomechanics and clinical testing at Pre Assessment with their C-Leg, participants will be fitted with a Bio-Leg prosthesis at the prosthetist clinic. The participant will train and use the Bio-Leg prosthesis during a 4-6 week acclimation period. The participant will then complete the same biomechanics and clinical testing at Post Assessment. | Device | Bio Leg |
Primary outcome
Change in 6-Minute Walk Test (6MWT)
Time frame: Baseline, 4-6 weeks
The distance that a patient should walk based on their height, weight, age, and gender. Performance assessment of walking endurance for 6 minutes. An increase in the number of meters walked during this assessment reflects an improvement in walking endurance.
Change in Interlimb Symmetry (Ground Reaction Forces)
Time frame: Baseline, 4-6 weeks
A direct measure of vertical ground reaction forces during the rising phase of a sit-to-stand task (measured in Newtons) using standard force plates embedded in the floor. Increased symmetry in ground reaction forces between the lower limbs reflects improved equalization of weight distribution between the limbs.
Change in Metabolic Efficiency (O2/kg/m)
Time frame: Baseline, 4-6 weeks
A direct measure assessed during the six-minute walk test. Metabolic efficiency is determined by the energy cost of transport, defined as oxygen consumption per unit body weight and distance walked (O₂/kg/m), which accounts for the individual's weight and walking speed. Improved metabolic efficiency reflects enhanced oxygen delivery and utilization during walking.
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 26 Oct 2026.
- 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.
Emily J Fox, PT, DPT, MHS, PhD principal investigator
University of Florida & Brooks Rehabilitation
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Bio Leg in people with Amputation of Lower Limb Above Knee and Amputee, run by University of Florida 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 5 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 26 Oct 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 Emily J Fox, PT, DPT, MHS, PhD (904-742-2500, ejfox@phhp.ufl.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in 6-Minute Walk Test (6MWT) (time frame: Baseline, 4-6 weeks). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 26 Oct 2026.