Limb Health and Socket Pressure in Response to Powered Ankle Prostheses
Abstract
The objectives of this project are to understand how the use of different components in the ankle and foot of a prosthesis affects the loading experienced by the residual limb during walking activities and then, ultimately, the overall health of that residual limb. Many ankle-foot prostheses for individuals who have had a below-knee amputation are passive, so they just contain spring-like elements. These prostheses do not allow the user to control the position of the ankle or to actively push off with the ankle while walking the way that an individual with an intact lower limb could. Some more advanced ankle-foot prostheses, known as microprocessor-controlled prostheses, contain batteries and a motor to adjust the ankle angle when the prosthesis is off the ground. This functionality can help reduce tripping hazards and make climbing stairs or ramps easier. Other similarly advanced prostheses, known as powered prostheses, contain batteries and a motor strong enough to approximate the push-off motion of an intact ankle-foot when in contact with the ground. These devices can help increase natural walking speeds and achieve walking motions more similar to those prior to amputation. With all of these prostheses, an individual wears a socket that provides the connection to the residual limb. Since the skin and soft tissue of the residual limb were not designed to support the weight of an individual, the loading they experience inside the socket can cause discomfort and sores. Relatively little is known about how the use of microprocessor-controlled and powered prostheses affects the loading, and no previous work has measured how they affect residual limb health. This study aims to fill that critical knowledge gap. By understanding how these different prostheses affect socket loading and residual limb health, a well-fitting socket can be custom fabricated for an individual, and the settings of the active prostheses can be tailored to increase comfort. This is important because persistent discomfort can lead a person to temporarily stop using or completely reject the use of a prosthesis. That would be particularly tragic because active prostheses have been shown to help individuals for whom they are appropriate achieve better mobility than any alternative devices. At present, these active prostheses are primarily used by individuals with at least the ability to walk with differing step lengths and speeds, up to the speed needed for typical participation in the community, and who can overcome most barriers encountered in common activities. Therefore, it is these individuals who will primarily benefit from the research. Individuals with less capability might benefit in the future if technological advances enable these types of prostheses to be useful for them as well. The benefit will come from enhanced comfort with the prosthesis so that users can wear it longer and for engaging in more rigorous activities. In the clinic, a prosthetist is a trained professional who helps people find the right combination of prosthetic components to achieve their maximum mobility for activities of daily living. This research will provide critical information to prosthetists for that selection of the other components that accompany a powered prosthesis. It will also help a prosthetist make changes when an individual experiences discomfort with existing prosthetic components. The risks associated with this research are very minor since a licensed prosthetist will introduce subjects to new active prostheses as would normally happen in a clinic. Subjects will try out each of two new prostheses for 4 weeks, and only non-invasive data will be collected during the visits for the study. Patient-related benefits could be achieved immediately upon completion of the 2-year project when the data are published and disseminated. Prosthetists in clinics throughout the country could take the findings of the research and apply them immediately in their decision-m
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Dec 05, 2021
- Source ID
- W81XWH2110459
Entities
People
- Sashwati Roy
Organizations
- Indiana University
- United States Army