Prosthesis UserNCT05279885
Efficacy of a Vented Liner and Socket System for Individuals With Trans-femoral Amputation
A study testing Vented suspension system and Non-vented suspension system in people with Prosthesis User, run by Jóna Valgerður Kristjánsdóttir at 1 site in United States.
Trial summary
The objective of the investigation is to measure the humidity within a transfemoral amputee's prosthesis during physical activity in a pre-heated room, using both the vented AeroFit system and a non-vented comparator. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Prosthesis User
- What is being tested?
- Vented suspension system and Non-vented suspension system
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 13 participants
- Where
- 1 siteUnited States
- Study dates
- 22 Oct 2021to 10 Mar 2022
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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
- 50Kg< body weight < 136Kg
- Cognitive ability to understand all instructions and questionnaires in the study
- Unilateral/ bilateral trans-femoral amputee
- Able to walk on a treadmill for 20 minutes
- Using Össur Seal-In Silicone Liner and Direct Socket
- Stump Length: Subjects must fall into the predefined criteria for minimum stump length dependent on liner size and residual limb shape
Show all 11Show fewer
- Direct Socket Length: Subjects must fall into the predefined criteria for minimum socket length dependent on liner size and residual limb shape. Measured from the distal end of the socket to the lowermost point on the medial side of the socket.
- Residual limb profile: Standard or conical
- Willing and able to participate in the study and follow the protocol
- Confident prosthetic users for more than 3 months
- Older than 18 years
Who cannot join
- 50Kg> body weight > 136Kg
- Users with cognitive impairment
- Participating in another research study
- Previous diagnosis or history of cardiovascular disease
Trial locations and contacts
1 site in 1 country.
United States1 site
SRT Prosthetics & Orthotics NPC - National Prosthetic Center
Indianapolis, Indiana, 46202
About this study
The objective of the investigation is to measure the humidity within a transfemoral amputee's prosthesis during physical activity in a pre-heated room, using both the vented AeroFit system and a non-vented comparator.
The AeroFit System is a vented suspension system for transfemoral amputees, and it is combined with both a vented liner and a vented socket. Both the liner and the socket are designed to allow humidity to evaporate from the residual limb skin and out of the socket. The system is intended to reduce sweat build-up on the amputees' residual limb.
Read more
At least ten transfemoral amputees will be fitted to the AeroFit socket and liner. After a minimum of 2 weeks of adaptation, subjects will have two humidity measurement sessions on two separate days, one day for the investigational device and one for the comparator. Each measurement session will take place during the same time of the day.
During the humidity measurement sessions, humidity and temperature sensors will be placed directly on the subject's residual limb, and the subject will walk for 20 minutes at self-selected walking speed on a treadmill in a pre-heated room of 28 degrees Celsius. After 20 minutes of walking and 10 minutes of rest, the subject will perform the four square step test and walk stairs and humidity and temperature measurements will be collected throughout the whole time. After the stairs activity, the subject will be seated and will remove the socket, liner and sensors.
The subject group will be randomized into two groups, A and B. Group A's first measurement session will be using the investigational device, Group B's first measurement session will be using the comparator.
Amputees often deal with sweat inside their prostheses, which can affect their suspension and skin health. The Aerofit system is intended to assist with that problem. The investigation is the first step in collecting a pivotal dataset to confirm the sweat build-up inside amputees' prosthesis is reduced with a breathable suspension system.
Read the detailed description
The clinical investigation will be a pre-market, confirmatory, pivotal clinical investigation. The clinical investigation will be designed to collect data on the effectiveness and clinical performance of AeroFit, the investigational device. Burden to subjects is interventional. Results from early feasibility clinical investigation on objective humidity measurements on skin indicate that the vented AeroFit TF system (investigational device) reduces the amount of humidity collected on skin during period of exercise in heated room compared to non-vented suspension system. Self-reported measures indicate no worse experience with the new vented system with regards to subjects perceived comfort, suspension and stability.
Investigational device will be Aerofit system, a vented liner and socket system which allows for humidity evaporation from subject.
The clinical investigation is a randomized cross-over design. Measurements on comparator and investigational device will be randomized.
The primary objective of the investigation will be to evaluate the efficacy of the vented investigational device compared to conventional non-vented suspension system regarding measured relative humidity on skin during increased perspiration. Secondary objectives are to evaluate if the measured moisture reduction during increased perspiration results in reduction in perceived moisture on skin. Tertiary objectives are to evaluate equivalent perceived system stability, suspension and comfort between investigational device and comparator.
Absorbent sweat patches will be used to collect quantifiable measures on amount of sweat collected on skin after the physical activity. Outcome from sweat patches measurement will only be exploratory. The patches will be analyzed to generate a microbiology culture report for exploratory purposes without related hypothesis. Outcomes from stair walking and FSST will also be exploratory.
The following clinical claims are to be evaluated:
- Measured moisture on skin is reduced
- Perceived moisture on skin is reduced
- Perceived stability is no worse
- Perceived suspension is no worse
- Perceived comfort is no worse
The subjects will use the investigational device (AeroFit System) for 3-10 weeks. Formal testing days for humidity measurements will be two days for each subject. Approximately 3-4 hours/day, one day for comparator testing and one day for investigational device testing.
Testing days will take place 2-9 weeks after the subject has been fitted to the investigational device. A minimum of 2 weeks adaptation time will be required before testing takes place.
After testing days have been completed, subject will get a new appointment at the clinic, and will be fitted back to their prescribed device.
From being fitted to the investigational device and until subjects are back to prescribed device, subjects are expected to use the investigational device for their daily living activities as they would with any other prosthesis, for up to 18 hours a day depending on the amputee.
The comparator device will be Össur Seal-In Silicone Liner in combination with AeroFit Socket. The holes of the socket will be sealed with a silicone sheet during testing for the purpose of closing off holes and thereby prevent any moisture evaporation from the socket. The chance of moisture evaporation is extremely small when subject is using enclosed silicone liner underneath an open socket, but to completely prevent the possibility, the holes will be sealed. The function of the AeroFit Socket, during comparator testing, will therefore be the same as a standard, enclosed, Direct Socket. The Össur Seal-In Silicone liner has the same intended use as the AeroFit Liner. Furthermore, it is indicated for the same condition and population group. It is a widely accepted device, providing clinical benefits to the user, and one of the most common type of such a device on the market.
The subject will be using the remaining part of their current prosthetic system (prosthetic knee and foot) with the investigational device, as it is used with the comparator device.
No other device, medication or intervention will be used. 10 subjects are to be enrolled and therefore 10 investigational systems (socket and liner) will be used for testing, as the devices are intended to be used by a single subject: one for each subject. All subjects will be provided with two AeroFit TF liners to use during daily activities, before and after the humidity measurement days.
Procedures There are six scheduled study events.
Screening Potential subjects will be identified from the customer base of SRT, the National Prosthetic Center. Co-Investigator (CI) evaluates, based on previous experience of interaction with and servicing of patients, if a potential participant is cognitively capable. If a potential participant fits the inclusion and exclusion criteria the CI will contact them via telephone. During the telephone call the CI will verify if they are interested in participating in a study. If interest is expressed at this point, CI will go through the enrollment log and if the eligibility criteria is met an appointment will be made for the first site visit and signing of the ICF. Questions relating to the duration of the study, number of clinical visits required, and the investigational device will be answered.
Potential risk of participating in the investigation will be explained to the subject at this point.
The CI will communicate to the PI and study monitor the number of users he has identified that meet the inclusion criteria and are willing to participate.
Training and protocol test run Training and protocol test run will take place prior to start of formal investigation procedures and data collection. Sponsor research assistances will handle training and take part in protocol procedures test run.
Visit 1 - Informed Consent and Investigational Device fitting At the initial visit, the first study event, for each subject a researcher qualified to obtain informed consent will seat the subject and proceed as described in chapter 13.8 Informed consent.
Fitting of the investigational device: All subjects will be fitted within the standard methods of prosthetic fitting, alignment, introduction, training and walking on various terrain.
Next, subject will be randomized into either group A or B. Group A will start with visit 2A, Group B will start with visit 2B. Randomization allocation will be done using envelopes including either the letter A or B. 10 subjects are required to complete the protocol procedures and therefore 5 envelopes will be prepared per letter.
Visits 2A and 2B - Humidity measurements in heated room (28 degrees Celsius), functional tests, and questionnaires.
- Visit 2A: Investigational Device humidity measurements
- Visit 2B: Comparator humidity measurements Visits 2A and 2B will take place on two separate days, during the same time of the day.
Humidity measurement procedure is the same for investigational device and comparator. Only difference is that for comparator testing, additional silicone sheets will be used to close socket body holes prior to test procedures start. Additionally, absorbent sweat patches will be placed on the participant's skin surface with the purpose of utilizing Gravimetric techniques for microbial analysis and in order to collect quantifiable measures on amount of sweat collected on subjects' skin after physical activity in heated room.
Visit 3 Fitting back to prescribed device. All subjects will be fitted within the standard methods of prosthetic fitting, alignment, introduction, training and walking on various terrain.
The investigational device will be provided as needed for the study population. Devices will not be packaged but will be labeled according to FDA regulatory requirements. Subjects will not be blinded.
The LPI will keep records documenting the receipt, use and return of the investigational device in the Investigational Device Management Form.
Statistical design and procedures The area under the relatively humidity curve from the time of donning the liner to the time of exiting the hot room will be the primary outcome to assess the efficacy of the intervention. The test liner will be compared to the control liner using a generalized linear model. Relative humidity at the time point immediately prior to liner donning will be included in the model as a covariate.
Perceived sweat will be compared with a one-sample, two-tailed t-test. All CLASS subscales will be compared using a one-tailed Wilcoxon-Signed-Ranks test.
Acceptance criteria for the data, as applicable, is defined in Table 6 Endpoints, test methods and hypotheses. Subgroup analysis will not be performed as no subgroups are defined.
Sample size calculation It is expected that 10 subjects are required to complete the protocol with a power of 0.95 and significance at 0,05. Effect size was estimated based early feasibility investigation results.
For pass/fail criteria, see Table 6 Endpoints, test methods and hypotheses.
Additional statistical matters There is no provision for interim analysis and no criteria for early termination of the clinical investigation on statistical grounds.
Any deviations from the statistical plan provided in this protocol will have to be approved by the sponsor and the reasons for the deviation reported in the clinical investigational report. Dropouts and withdrawn participants will be included in the data analysis for the procedures that they completed. They will be grouped together and compared to the group that finished the protocol. Any statistical differences of the two groups will be reported. If the participants have not provided any data, they will not be included in the data analysis. No particular information will be excluded from the statistical analysis and tests, as described above.
The clinical investigation is sponsored by Össur Iceland ehf.
It shall be conducted:
- in accordance with the ethical principles that have their origin in the Declaration of Helsinki
- in compliance with the ISO 14155 International Standard
- in compliance with any regional or national legislations, as applicable The clinical investigation shall not commence until the required approval from the IRB/REB/REC, and regulatory authority as applicable, has been obtained.
Any additional requirements imposed by the IRB/REB/REC or regulatory authority shall be followed, as applicable.
Subjects are provided with health insurance with expenses covered of up to 5.000.000 USD relating to any adverse health outcomes in relation the clinical investigation.
A patient using the investigational device may or may not benefit clinically from using the device vis-a-vis using another Össur Seal-In® TF silicone liner and Direct Socket commercially available.
Expected benefits while using the investigational device:
- Measured moisture on skin is reduced
- Perceived moisture on skin is reduced
- Perceived stability is no worse
- Perceived suspension is no worse
- Perceived comfort is no worse Compared to not using an Össur Seal-In® TF silicone liner and Direct Socket, in combination with the remaining part of the prosthesis, the patient will benefit significantly in terms of mobility and ability to live independently. Further on the user will be trained on a new prosthetic component to experience the unprecedented functionality of the new component to mitigate the known deficiencies associated with his amputation.
Additionally, the benefit for the user during the testing is that he/she helps in developing a new and novel vented Össur TF silicone liner and socket design.
- Conditions
- Prosthesis User
- Being tested
- Vented suspension system, Non-vented suspension system
- Keywords
- prosthesis, amputee, trans-femoral, liner, seal, silicone, sweat, moisture
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vented suspension systemDevice
The AeroFit TF Liner is a vented silicone liner which allows for humid evaporation from the amputee's skin and through the liner.
The AeroFit TF Socket is made in the same way as conventional Direct Socket, but in addition, perforations are drilled to the body of the socket and vents inserted into each perforation which allows for moisture evaporation from between liner and socket and out of socket. Overmolded textile on the outside of the vents covers the perforations to prevent dirt and dust to enter the socket.
Non-vented suspension systemDevice
Össur HSM Seal-In Silicon liner (non-vented)
| Study group | Role | What they receive |
|---|---|---|
| Group A - Vented Suspension System First, Non-vented Second | Other | Subjects will be randomized in to two groups, A and B. Group A starts with humidity measurements on vented suspension system. Receives: Device: Vented suspension system; Device: Non-vented suspension system |
| Group B - Non-vented Suspension System First, Vented Second | Other | Subjects will be randomized in to two groups, A and B. Group B starts with humidity measurements on non-vented suspension system. Receives: Device: Vented suspension system; Device: Non-vented suspension system |
What is being measured
The primary outcome is the main question the study is designed to answer.
Area Under the Relative Humidity-Time Curve Ratio (Residual Limb/Sound Limb)
Relative humidity (rH) and temperature data were acquired using an MSR147WD wireless data logger system with sensors (MSR Electronics GmbH, Seuzach, Switzerland). Relative humidity was measured within the prosthetic liner on the residual limb and on the sound limb during treadmill walking in a heated room. The area under the relative humidity-time curve (AUC) was calculated over the measurement period using the trapezoidal rule implemented in locally written MATLAB® code. For each subject and test condition, the residual limb AUC was normalized by dividing it by the corresponding sound limb AUC: Normalized AUC = Residual limb rH AUC ÷ Sound limb rH AUC.
The reported outcome is this ratio. A value of 1 indicates that the rH over time on the residual limb was equal to the sound limb. Values greater than 1 indicate greater cumulative rH on the residual limb relative to the sound limb, whereas values less than 1 indicate lower cumulative rH. Lower values represent more favorable outcome.
Measured: measurement day 1 (either vented or non-vented system depending on which intervention group) vs measurement day 2 (either vented or non-vented system depending on which intervention group)
Secondary outcomes (1)
Perceived on Skin Humidity
Subjects rated their perceived sweat during the treadmill walking in a heated room on a scale from 1-10 where 1 is an extreme amount of sweat, and 10 is no sweat at all. A higher score corresponds to less perceived sweat on the skin within the liner.
Measured: measurement day 1 (either vented or non-vented system depending on which intervention group) vs measurement day 2 (either vented or non-vented system depending on which intervention group)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Mar 2022
- Study start22 Oct 2021
- Primary completion10 Mar 2022
- Study completion10 Mar 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Prosthesis UserStudies 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
- Crossover
- Masking
- None (open label)
- Enrolment
- 13 participants (actual)
Sponsor and investigators
- Lead sponsor
- Jóna Valgerður Kristjánsdóttir
- Sponsor type
- Industry (pharma, biotech, devices)
- Collaborators
- Indiana University
- Responsible party
- Sponsor-investigator, Jóna Valgerður Kristjánsdóttir, Össur Iceland ehf
- Investigators
- Sashwati Roy, PhD, Principal investigator, Indiana University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05279885
- Sponsor's protocol ID
- CIP2021042902
- Status last verified
- Sep 2026
- First submitted
- 9 Nov 2021
- Last updated
- 21 Oct 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 21 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Efficacy of a Vented Liner and Socket System for Individuals With Trans-femoral Amputation
- ClinicalTrials.gov ID
- NCT05279885
- Acronym / sponsor ID
- CIP2021042902
- Conditions
- Prosthesis User
- Keywords
- prosthesis, amputee, trans-femoral, liner, seal, silicone, sweat, moisture
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 13 participants (actual)
- Lead sponsor
- Jóna Valgerður KristjánsdóttirIndustry (pharma, biotech, devices)
- Collaborators
- Indiana University
- Study start
- 22 Oct 2021 (actual)
- Primary completion
- 10 Mar 2022 (actual)
- Study completion
- 10 Mar 2022 (actual)
- First posted
- 15 Mar 2022 (actual)
- Results
- Posted 21 Oct 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The objective of the investigation is to measure the humidity within a transfemoral amputee's prosthesis during physical activity in a pre-heated room, using both the vented AeroFit system and a non-vented comparator.
The AeroFit System is a vented suspension system for transfemoral amputees, and it is combined with both a vented liner and a vented socket. Both the liner and the socket are designed to allow humidity to evaporate from the residual limb skin and out of the socket. The system is intended to reduce sweat build-up on the amputees' residual limb.
At least ten transfemoral amputees will be fitted to the AeroFit socket and liner. After a minimum of 2 weeks of adaptation, subjects will have two humidity measurement sessions on two separate days, one day for the investigational device and one for the comparator. Each measurement session will take place during the same time of the day.
During the humidity measurement sessions, humidity and temperature sensors will be placed directly on the subject's residual limb, and the subject will walk for 20 minutes at self-selected walking speed on a treadmill in a pre-heated room of 28 degrees Celsius. After 20 minutes of walking and 10 minutes of rest, the subject will perform the four square step test and walk stairs and humidity and temperature measurements will be collected throughout the whole time. After the stairs activity, the subject will be seated and will remove the socket, liner and sensors.
The subject group will be randomized into two groups, A and B. Group A's first measurement session will be using the investigational device, Group B's first measurement session will be using the comparator.
Amputees often deal with sweat inside their prostheses, which can affect their suspension and skin health. The Aerofit system is intended to assist with that problem. The investigation is the first step in collecting a pivotal dataset to confirm the sweat build-up inside amputees' prosthesis is reduced with a breathable suspension system.
Detailed description
The clinical investigation will be a pre-market, confirmatory, pivotal clinical investigation. The clinical investigation will be designed to collect data on the effectiveness and clinical performance of AeroFit, the investigational device. Burden to subjects is interventional. Results from early feasibility clinical investigation on objective humidity measurements on skin indicate that the vented AeroFit TF system (investigational device) reduces the amount of humidity collected on skin during period of exercise in heated room compared to non-vented suspension system. Self-reported measures indicate no worse experience with the new vented system with regards to subjects perceived comfort, suspension and stability.
Investigational device will be Aerofit system, a vented liner and socket system which allows for humidity evaporation from subject.
The clinical investigation is a randomized cross-over design. Measurements on comparator and investigational device will be randomized.
The primary objective of the investigation will be to evaluate the efficacy of the vented investigational device compared to conventional non-vented suspension system regarding measured relative humidity on skin during increased perspiration. Secondary objectives are to evaluate if the measured moisture reduction during increased perspiration results in reduction in perceived moisture on skin. Tertiary objectives are to evaluate equivalent perceived system stability, suspension and comfort between investigational device and comparator.
Absorbent sweat patches will be used to collect quantifiable measures on amount of sweat collected on skin after the physical activity. Outcome from sweat patches measurement will only be exploratory. The patches will be analyzed to generate a microbiology culture report for exploratory purposes without related hypothesis. Outcomes from stair walking and FSST will also be exploratory.
The following clinical claims are to be evaluated:
- Measured moisture on skin is reduced
- Perceived moisture on skin is reduced
- Perceived stability is no worse
- Perceived suspension is no worse
- Perceived comfort is no worse
The subjects will use the investigational device (AeroFit System) for 3-10 weeks. Formal testing days for humidity measurements will be two days for each subject. Approximately 3-4 hours/day, one day for comparator testing and one day for investigational device testing.
Testing days will take place 2-9 weeks after the subject has been fitted to the investigational device. A minimum of 2 weeks adaptation time will be required before testing takes place.
After testing days have been completed, subject will get a new appointment at the clinic, and will be fitted back to their prescribed device.
From being fitted to the investigational device and until subjects are back to prescribed device, subjects are expected to use the investigational device for their daily living activities as they would with any other prosthesis, for up to 18 hours a day depending on the amputee.
The comparator device will be Össur Seal-In Silicone Liner in combination with AeroFit Socket. The holes of the socket will be sealed with a silicone sheet during testing for the purpose of closing off holes and thereby prevent any moisture evaporation from the socket. The chance of moisture evaporation is extremely small when subject is using enclosed silicone liner underneath an open socket, but to completely prevent the possibility, the holes will be sealed. The function of the AeroFit Socket, during comparator testing, will therefore be the same as a standard, enclosed, Direct Socket. The Össur Seal-In Silicone liner has the same intended use as the AeroFit Liner. Furthermore, it is indicated for the same condition and population group. It is a widely accepted device, providing clinical benefits to the user, and one of the most common type of such a device on the market.
The subject will be using the remaining part of their current prosthetic system (prosthetic knee and foot) with the investigational device, as it is used with the comparator device.
No other device, medication or intervention will be used. 10 subjects are to be enrolled and therefore 10 investigational systems (socket and liner) will be used for testing, as the devices are intended to be used by a single subject: one for each subject. All subjects will be provided with two AeroFit TF liners to use during daily activities, before and after the humidity measurement days.
Procedures There are six scheduled study events.
Screening Potential subjects will be identified from the customer base of SRT, the National Prosthetic Center. Co-Investigator (CI) evaluates, based on previous experience of interaction with and servicing of patients, if a potential participant is cognitively capable. If a potential participant fits the inclusion and exclusion criteria the CI will contact them via telephone. During the telephone call the CI will verify if they are interested in participating in a study. If interest is expressed at this point, CI will go through the enrollment log and if the eligibility criteria is met an appointment will be made for the first site visit and signing of the ICF. Questions relating to the duration of the study, number of clinical visits required, and the investigational device will be answered.
Potential risk of participating in the investigation will be explained to the subject at this point.
The CI will communicate to the PI and study monitor the number of users he has identified that meet the inclusion criteria and are willing to participate.
Training and protocol test run Training and protocol test run will take place prior to start of formal investigation procedures and data collection. Sponsor research assistances will handle training and take part in protocol procedures test run.
Visit 1 - Informed Consent and Investigational Device fitting At the initial visit, the first study event, for each subject a researcher qualified to obtain informed consent will seat the subject and proceed as described in chapter 13.8 Informed consent.
Fitting of the investigational device: All subjects will be fitted within the standard methods of prosthetic fitting, alignment, introduction, training and walking on various terrain.
Next, subject will be randomized into either group A or B. Group A will start with visit 2A, Group B will start with visit 2B. Randomization allocation will be done using envelopes including either the letter A or B. 10 subjects are required to complete the protocol procedures and therefore 5 envelopes will be prepared per letter.
Visits 2A and 2B - Humidity measurements in heated room (28 degrees Celsius), functional tests, and questionnaires.
- Visit 2A: Investigational Device humidity measurements
- Visit 2B: Comparator humidity measurements Visits 2A and 2B will take place on two separate days, during the same time of the day.
Humidity measurement procedure is the same for investigational device and comparator. Only difference is that for comparator testing, additional silicone sheets will be used to close socket body holes prior to test procedures start. Additionally, absorbent sweat patches will be placed on the participant's skin surface with the purpose of utilizing Gravimetric techniques for microbial analysis and in order to collect quantifiable measures on amount of sweat collected on subjects' skin after physical activity in heated room.
Visit 3 Fitting back to prescribed device. All subjects will be fitted within the standard methods of prosthetic fitting, alignment, introduction, training and walking on various terrain.
The investigational device will be provided as needed for the study population. Devices will not be packaged but will be labeled according to FDA regulatory requirements. Subjects will not be blinded.
The LPI will keep records documenting the receipt, use and return of the investigational device in the Investigational Device Management Form.
Statistical design and procedures The area under the relatively humidity curve from the time of donning the liner to the time of exiting the hot room will be the primary outcome to assess the efficacy of the intervention. The test liner will be compared to the control liner using a generalized linear model. Relative humidity at the time point immediately prior to liner donning will be included in the model as a covariate.
Perceived sweat will be compared with a one-sample, two-tailed t-test. All CLASS subscales will be compared using a one-tailed Wilcoxon-Signed-Ranks test.
Acceptance criteria for the data, as applicable, is defined in Table 6 Endpoints, test methods and hypotheses. Subgroup analysis will not be performed as no subgroups are defined.
Sample size calculation It is expected that 10 subjects are required to complete the protocol with a power of 0.95 and significance at 0,05. Effect size was estimated based early feasibility investigation results.
For pass/fail criteria, see Table 6 Endpoints, test methods and hypotheses.
Additional statistical matters There is no provision for interim analysis and no criteria for early termination of the clinical investigation on statistical grounds.
Any deviations from the statistical plan provided in this protocol will have to be approved by the sponsor and the reasons for the deviation reported in the clinical investigational report. Dropouts and withdrawn participants will be included in the data analysis for the procedures that they completed. They will be grouped together and compared to the group that finished the protocol. Any statistical differences of the two groups will be reported. If the participants have not provided any data, they will not be included in the data analysis. No particular information will be excluded from the statistical analysis and tests, as described above.
The clinical investigation is sponsored by Össur Iceland ehf.
It shall be conducted:
- in accordance with the ethical principles that have their origin in the Declaration of Helsinki
- in compliance with the ISO 14155 International Standard
- in compliance with any regional or national legislations, as applicable The clinical investigation shall not commence until the required approval from the IRB/REB/REC, and regulatory authority as applicable, has been obtained.
Any additional requirements imposed by the IRB/REB/REC or regulatory authority shall be followed, as applicable.
Subjects are provided with health insurance with expenses covered of up to 5.000.000 USD relating to any adverse health outcomes in relation the clinical investigation.
A patient using the investigational device may or may not benefit clinically from using the device vis-a-vis using another Össur Seal-In® TF silicone liner and Direct Socket commercially available.
Expected benefits while using the investigational device:
- Measured moisture on skin is reduced
- Perceived moisture on skin is reduced
- Perceived stability is no worse
- Perceived suspension is no worse
- Perceived comfort is no worse Compared to not using an Össur Seal-In® TF silicone liner and Direct Socket, in combination with the remaining part of the prosthesis, the patient will benefit significantly in terms of mobility and ability to live independently. Further on the user will be trained on a new prosthetic component to experience the unprecedented functionality of the new component to mitigate the known deficiencies associated with his amputation.
Additionally, the benefit for the user during the testing is that he/she helps in developing a new and novel vented Össur TF silicone liner and socket design.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group A - Vented Suspension System First, Non-vented Second | Other | Device: Vented suspension system, Device: Non-vented suspension systemSubjects will be randomized in to two groups, A and B. Group A starts with humidity measurements on vented suspension system. |
| Group B - Non-vented Suspension System First, Vented Second | Other | Device: Vented suspension system, Device: Non-vented suspension systemSubjects will be randomized in to two groups, A and B. Group B starts with humidity measurements on non-vented suspension system. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- 50Kg< body weight < 136Kg
- Cognitive ability to understand all instructions and questionnaires in the study
- Unilateral/ bilateral trans-femoral amputee
- Able to walk on a treadmill for 20 minutes
- Using Össur Seal-In Silicone Liner and Direct Socket
Key exclusion criteria (4 listed)
- 50Kg> body weight > 136Kg
- Users with cognitive impairment
- Participating in another research study
- Previous diagnosis or history of cardiovascular disease
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 |
|---|---|---|
| Vented suspension systemThe AeroFit TF Liner is a vented silicone liner which allows for humid evaporation from the amputee's skin and through the liner. The AeroFit TF Socket is made in the same way as conventional Direct Socket, but in addition, perforations are drilled to the body of the socket and vents inserted into each perforation which allows for moisture evaporation from between liner and socket and out of socket. Overmolded textile on the outside of the vents covers the perforations to prevent dirt and dust to enter the socket. | Device | Group A - Vented Suspension System First, Non-vented Second, Group B - Non-vented Suspension System First, Vented Second |
| Non-vented suspension systemÖssur HSM Seal-In Silicon liner (non-vented) | Device | Group A - Vented Suspension System First, Non-vented Second, Group B - Non-vented Suspension System First, Vented Second |
Primary outcome
Area Under the Relative Humidity-Time Curve Ratio (Residual Limb/Sound Limb)
Time frame: measurement day 1 (either vented or non-vented system depending on which intervention group) vs measurement day 2 (either vented or non-vented system depending on which intervention group)
Relative humidity (rH) and temperature data were acquired using an MSR147WD wireless data logger system with sensors (MSR Electronics GmbH, Seuzach, Switzerland). Relative humidity was measured within the prosthetic liner on the residual limb and on the sound limb during treadmill walking in a heated room. The area under the relative humidity-time curve (AUC) was calculated over the measurement period using the trapezoidal rule implemented in locally written MATLAB® code. For each subject and test condition, the residual limb AUC was normalized by dividing it by the corresponding sound limb AUC: Normalized AUC = Residual limb rH AUC ÷ Sound limb rH AUC. The reported outcome is this ratio. A value of 1 indicates that the rH over time on the residual limb was equal to the sound limb. Values greater than 1 indicate greater cumulative rH on the residual limb relative to the sound limb, whereas values less than 1 indicate lower cumulative rH. Lower values represent more favorable outcome.
1 secondary outcome
Perceived on Skin Humidity
Time frame: measurement day 1 (either vented or non-vented system depending on which intervention group) vs measurement day 2 (either vented or non-vented system depending on which intervention group)
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Oct 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- 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. This study is not recruiting at the moment.
Sashwati Roy, PhD principal investigator
Indiana University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Vented suspension system and Non-vented suspension system in people with Prosthesis User, run by Jóna Valgerður Kristjánsdóttir 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 11 inclusion and 4 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: finished, as of the sponsor's last update on 21 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?
Yes. Results are posted in the registry (first posted 21 Oct 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Area Under the Relative Humidity-Time Curve Ratio (Residual Limb/Sound Limb) (time frame: measurement day 1 (either vented or non-vented system depending on which intervention group) vs measurement day 2 (either vented or non-vented system depending on which intervention group)). 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 21 Oct 2026.