An interventional study of Ottobock CLeg4 + Ottobock foot and SRALAB Hybrid Knee + Polycentric Ankle in Amputation, Amputation, Traumatic and Amputation of Knee, sponsored by Shirley Ryan AbilityLab. Recruiting at 1 site in United States. Open to participants aged 18 Years to 95 Years. Per ClinicalTrials.gov, last updated 2024-05-30.
Sponsored by Shirley Ryan AbilityLab · Not applicable, Interventional, and Basic science
The goal of this study is to understand how providing power at the knee or ankle individually, or providing power at both the knee and ankle, impacts ambulation for K2 level transfemoral amputees.
Aim 1: measure functional performance of K2 level ambulators when using a commercially available passive microprocessor knee prosthesis (Ottobock Cleg/Ottobock foot) or a powered knee and ankle prosthesis (SRALab Hybrid Knee and SRAlab Polycentric Powered Ankle.
Aim 2: Participants will be evaluated on the contribution of adding power at the knee only or the ankle only.
Aim 3: The investigators will evaluate the functional performance after intensive clinical gait training on the powered knee and ankle prosthesis (SRALab Hybrid Knee and SRALab Polycentric Powered Ankle).
Our hypothesis is that providing powered componentry will improve function and that intensive training will magnify those improvements.
Amputation of the lower limb causes profound disability, significantly limiting mobility, independence, and the ability to pursue employment or leisure activities. Nearly 90% of all lower limb amputations in the United States occur in older persons, mostly due to vascular disease, and this population is expected to triple by 2050. After lower limb loss, individuals walk more slowly and more asymmetrically are less stable, and expend more metabolic energy during walking than persons with intact limbs. Even when using state-of-the-art microprocessor-controlled prostheses (typically a microprocessor knee with a passive ankle), persons with transfemoral amputations expend approximately 60% more energy than able-bodied individuals during ambulation. In addition to the physical limitations caused by the amputation, the increased energy requirements affect performance of everyday activities, including getting up out of a chair or off the toilet, or stepping up or down a curb.
Most commercially available prosthetic legs are passive. The movement of a passive prosthetic joint relies on the properties of its mechanical components, such as hydraulic or pneumatic valves or sliding joints, together with compensatory adjustments made by the user. Since these computerized prostheses are passive, the user cannot efficiently negotiate stairs, an incline, or the numerous other functions that require net knee and/or ankle power.
Powered prostheses can actively generate joint torque, allowing easy and efficient performance of more demanding activities, such as ascending stairs and hills. Powered knees and ankles, may allow for better outcomes in both older and younger individuals with transfemoral amputation; this powered componentry may enable more energy efficient walking, allow users to stand up from a seated position with ease, and enable them to walk across more challenging terrains-such as up and down hills, ramps, and stairs-safely and with more normal and symmetric gait kinematics and kinetics.
This study will demonstrate the functional benefits of adding power at an individual joint. This knowledge will be critical for prioritizing future device development and will provide valuable information for clinicians and individuals on selecting appropriate componentry for transfemoral K2 amputees.
112 studies on the registry are indexed under Amputation, Traumatic; 24 are open to participants now.
This study's planned enrollment of 20 is above the median of 15 across 75 interventional studies indexed under Amputation, Traumatic.
Browse Amputation, Traumatic studies →Shirley Ryan AbilityLab is the lead sponsor of 180 studies on the registry; 44 are open to participants now.
Of its 10 completed or terminated interventional studies of FDA-regulated products, 4 (40%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participant is fit with the commercially available device (Ottobock Cleg 4/Ottobock foot), they will receive standard of care clinical training for 3-4 sessions over 4 weeks, plus 1 session for outcome assessments. Participant is then fit with the SRALAB Hybrid knee and SRALAB Polycentric Ankle prosthesis, they again will receive clinical training for 3-4 sessions over 4 weeks, plus 1 session for outcome assessments.
Device: Ottobock CLeg4 + Ottobock foot · Device: SRALAB Hybrid Knee + Polycentric Ankle
For this arm, transfemoral amputees will participate in an AB/BA randomized crossover study. Before each arm of the cross-over, baseline data will be taken with the Ottobock Cleg 4/Ottobock foot or their clinically prescribed microprocessor knee unit/foot. Condition A is CLeg + Polycentric Ankle Condition B is SRALab Hybrid knee + Passive Ankle Subjects will participate in 2 sessions over 2 weeks, each lasting 2-3 hours to have the device tuned for the specific condition (A or B). On the third week, they will participate in 2 visits to complete functional outcome measures, biomechanical and metabolic assessments. They will then switch conditions, and repeat the protocol for the second condition. There will not be a washout period between conditions, but subjects will complete outcome measures with the Ottobock Cleg 4/Ottobock foot or their clinically prescribed microprocessor knee unit/foot prior to each arm of the crossover to obtain baseline data.
Device: SRALAB Hybrid Knee + Passive Ankle · Device: Ottobock CLeg 4 + Polycentric Ankle
During this arm, participants will receive intensive clinical training with the SRALAB Hybrid knee + Polycentric Ankle twice per week over 8 weeks, lasting 2-3 hours. Training will include patient-driven therapy to achieve participants' individual therapy goals, functional mobility and community skills. At the end of the 8-week training period, subjects will complete the same set of functional outcome measures, biomechanical and metabolic assessments in previous arms. To complete this arm, participants will again complete training and outcome measures with the Ottobock Cleg4/Ottobock or their clinically prescribed microprocessor knee unit/foot over 3 visits.
Device: Ottobock CLeg4 + Ottobock foot · Device: SRALAB Hybrid Knee + Polycentric Ankle
Commercially available Ottobock CLeg 4 microprocessor knee unit and Ottobock foot.
Experimental powered prosthesis: SRALAB Hybrid Knee and powered polycentric ankle.
Experimental powered prosthesis: SRALAB Hybrid Knee and passive ankle.
Commercially available Ottobock CLeg 4 prosthetic knee and SRALAB powered polycentric ankle.
Amputee Mobility Predictor with Prosthesis (AMPRO) score
The AMPRO measures the ambulatory potential of lower limb amputees. It is used to assess functional mobility through a standardized sequence of mobility tests while using a prosthesis. Individual tasks are scored and combined, resulting in a total assessment score out of a possible 47; the minimum score is zero. Higher scores indicate better mobility. The AMPPRO is a reliable performance measure that has been validated for those with lower limb loss; it measures several functional mobility tasks that are needed during activities of daily living; it has been used to identify limitations in prosthetic mobility, including tasks that require both vertical mobility (sit/stand), horizontal mobility (walking), and balance. The AMPPRO scores have been shown to differentiate between Medicare K-levels and to provide information to guide therapeutic exercise techniques and document change after clinical instruction.
Time frame: Completed at visit during week 5, week 10, week 11, week 14, week 15, week 18, week 35 and week 38.
6 Minute Walk Test (6MWT)
The 6 minute walk test (6MWT) assesses distance walked over 6 minutes as a sub-maximal test of aerobic capacity/endurance.
Time frame: Completed at visit during week 5, week 10, week 11, week 14, week 15, week 18, week 35 and week 38.
Timed Up and Go (TUG)
The Timed Up and Go Test (TUG) assesses mobility, balance, walking ability, and fall risk in older adults.
Time frame: Completed at visit during week 5, week 10, week 11, week 14, week 15, week 18, week 35 and week 38.
Four Square Step Test (FSST)
A test of dynamic balance and coordination that clinically assesses the participant's ability to step over objects forward, sideways, and backwards.
Time frame: Completed at visit during week 5, week 10, week 11, week 14, week 15, week 18, week 35 and week 38.
Metabolic Testing
Subjects will be instrumented with the COSMED® K5 system (COSMED, Rome, Italy). Baseline metabolic data prior to each walking bout will be recorded for 2 minutes of sitting and quiet rest. Metabolic data will then be collected during 6 minutes of walking at a constant self-selected walking velocity on a treadmill. After each walking bout, subjects will rest for 20 minutes to allow their heart rate to return to their baseline level.
Time frame: Completed at visit during week 5, week 10, week 11, week 14, week 15, week 18, week 35 and week 38
Started May 2023 (actual). Primary completion is estimated for Jun 2028, 61 months after the start.
Of 38 non-industry interventional studies with no phase under Amputation, Traumatic, half reached primary completion within 31 months of starting (the median), counting those still running; a quarter within 13 and three quarters within 58. This study's planned 61 months is above that.
Counting every sponsor, half of 46 studies reached it within 27 months; a quarter within 14 and three quarters within 51.
How these figures are worked out, and which studies are left out of them.
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