Amputation, Amputation Stumps, Amputees, Lower Limb Deformities, Congenital, Prosthesis, Prosthesis User
Conditions
Keywords
cooling, amputee, lower limb difference, Prosthetic, socket, Prosthesis, Prosthetist, Liner, sweat, walking, sock, leg, perspiration, moisture, heat, thermal
Brief summary
The comfort and fit of the residual limb within a prosthetic socket are of primary concern for many amputees. The residual limb is typically covered by non-breathable and non- thermally conductive materials that can create a warm and ultimately moist environment. The investigators have developed a silicone liner approach to remove sweat from the skin and out of the socket and to passively conduct heat from the skin using thermally conductive elastomers. This liner has been developed to work alongside a thermo-electric cooling (TEC)-based module called the Intrasocket Cooling Element (ICE) developed in a parallel project by Vivonics, Inc. and Liberating Technologies, Inc. The ICE device can be embedded into the prosthesis in order to cool the residual limb. A technology that can provide thermal control while retaining adequate suspension, weight, and other prosthetic characteristics would benefit many prosthesis wearers.
Detailed description
The comfort and fit of the residual limb within a prosthetic socket are of primary concern for many amputees. The residual limb is typically covered by non-breathable and non- thermally conductive materials that can create a warm and ultimately moist environment. These layers consist of a prosthetic liner that rolls onto the limb and traps heat and occasional extra prosthetic socks. Studies found increases in socket temperature after the prosthesis was donned. Temperatures were found to remain elevated long after activity cessation and even a rest period of double the duration of the preceding activity period is insufficient to return the limb to its initial temperature. A small amount of activity can cause the socket temperature to elevate and remain at an uncomfortable level for an extended period of time, which can lead to decreased wear times. In summary, an uncomfortable socket/residual limb interface decreases prosthesis use among amputees who want to remain active in their lives. To address this, the investigators have developed a silicone liner approach to remove sweat from the skin and out of the socket and to passively conduct heat from the skin using thermally conductive elastomers. This liner has been developed to work alongside a thermo-electric cooling (TEC)-based module called the Intrasocket Cooling Element (ICE) developed in a parallel project by Vivonics, Inc. and Liberating Technologies, Inc. The ICE device can be embedded into the prosthesis in order to cool the residual limb. A technology that can provide thermal control while retaining adequate suspension, weight, and other prosthetic characteristics would benefit many prosthesis wearers. This study will focus on investigating the efficacy of this novel moisture and thermal management (experimental) liner. The rationale for this study is to determine how well the new technology can regulate the residual limb temperature, reduce the moisture generation, and remove excess moisture in a controlled laboratory environment. The objective of this study is to measure the effects experimental techniques of moisture and thermal management has on moisture and temperature in the socket. Moisture and thermal management of the residual limb inside the prosthetic socket could result in greater comfort while wearing the prosthesis, and ultimately could result in greater function and better quality of life (QoL). Other measures that may be collected are exploratory. A repeated measures study will be conducted to analyze the temperature and moisture generation of the residual limb with and without the experimental liner and active cooling system within a standard prosthetic socket. Both able-bodied research subjects, and lower limb amputee research subjects who use transfemoral or transtibial prostheses will be recruited for testing. Liners for able-bodies subjects will have the distal end removed to allow for donning. All subjects will visit Liberating Technologies, Inc. to be consented and to complete study testing. A maximum of 10 able-bodied and 20 lower-limb amputee subjects will be recruited for this study. This is increased from a target 12 subjects to account for any drop-outs, etc.
Interventions
A prototype prosthetic liner designed to reduce and/or remove moisture and heat that builds up on the limb.
The participant's usual prosthetic liner
Sponsors
Study design
Eligibility
Inclusion criteria
* Lower limb amputee * Be willing and able to complete the tasks outlined * Are at least 6 months on a definitive prosthesis * Fits within an experimental liner * Can understand English in order to be properly consented and provide their feedback to the study personnel
Exclusion criteria
* The risks to pregnant women and fetuses are unknown and therefore pregnant women should not participate in the study * Other unforeseen disqualifying criteria (such as specific cognitive issues, etc.)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Residual Limb Temperature | 2 hours | Changes in residual limb temperature during walking/resting measured with temperature sensors placed on the limb. Positive values signify a raise in temperature and negative values signify a drop in temperature between the start of walking to the end of walking. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Experimental Liner, Then Control Liner Participants will test the experimental prosthetic liner by walking on a treadmill while wearing the liner. They will then test the control liner by walking on the treadmill while wearing their usual prosthetic liner.
Moisture Management Liner: A prototype prosthetic liner designed to reduce and/or remove moisture and heat that builds up on the limb. | 1 |
| Control Liner, Then Experimental Liner Participants will test the control (participant's usual) liner by walking on a treadmill while wearing the liner. They will then test the experimental prosthetic liner by walking on a treadmill while wearing the liner.
Control Liner: The participant's usual prosthetic liner | 1 |
| Total | 2 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Unable to use the experimental liner due to suspension issues. Incomplete data collection. | 0 | 1 |
Baseline characteristics
| Characteristic | Experimental Liner, Then Control Liner | Control Liner, Then Experimental Liner | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 1 Participants | 1 Participants |
| Age, Categorical Between 18 and 65 years | 1 Participants | 0 Participants | 1 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 1 Participants | 1 Participants | 2 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 1 Participants | 1 Participants | 2 Participants |
| Sex: Female, Male Female | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Male | 1 Participants | 1 Participants | 2 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 2 | 0 / 2 |
| other Total, other adverse events | 0 / 2 | 0 / 2 |
| serious Total, serious adverse events | 0 / 2 | 0 / 2 |
Outcome results
Residual Limb Temperature
Changes in residual limb temperature during walking/resting measured with temperature sensors placed on the limb. Positive values signify a raise in temperature and negative values signify a drop in temperature between the start of walking to the end of walking.
Time frame: 2 hours
Population: Data only reported for the subject who completed both conditions.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Experimental Prosthetic Liner | Residual Limb Temperature | 3.0 Degrees Fahrenheit |
| Control Prosthetic Liner | Residual Limb Temperature | 3.2 Degrees Fahrenheit |