Quantifying Bone and Skin Movement in the Residual Limb-Socket Interface of Individuals With Transtibial Amputation Using Dynamic Stereo X-Ray
VA Office of Research and Development
Summary
Individuals with lower extremity amputation are often challenged by complications that arise from poor prosthetic fit, including movement of the residual limb in the socket, known as pistoning. Pistoning can lead to gait instability, skin problems, and pain. Different prosthetic suspension systems have been developed to decrease this motion, including elevated vacuum suspension, which utilizes a pump to draw air from the socket. However, scientific analyses to understand the movement between the limb and socket have yet to be performed with a high level of accuracy. This study will use a state-of-the art imaging technique, known as dynamic stereo x-ray, to quantify the 3D movement of the residual limb in the socket. It is hypothesized that dynamic stereo x-ray will be a sensitive method to measure differences in residual limb movement between 2 different socket suspension techniques: suction and elevated vacuum suspension. This information is critical for advancing prosthetic treatments to reduce secondary conditions and degenerative changes that result from poor prosthetic fit.
Description
Individuals with lower extremity amputation (LEA) often experience relative motion between their residual limb and the prosthetic socket, such as vertical translation and axial rotation, which can cause inefficient dynamic load transmission from the distal prosthetic components to the residual limb. This can lead to significant secondary consequences, such as pain, gait deviations, and discomfort that limit mobility and autonomy. Assessments of the relative motion between the bone and the prosthetic socket have been performed, but there is little existing data on dynamic, in vivo residual limb…
Eligibility
- Age range
- 18+ years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Unilateral transtibial amputation (any etiology) * At least 18 years old * At least 6-months post-amputation * Current prosthetic users (at least 6 hours/day) Exclusion Criteria: * Unable to ambulate on a treadmill at low to moderate speed * Inability to tolerate the socket suspensions * Length of the residual limb prohibits socket fitting, dynamic stereo x-ray data capture, or marker placement * Mental impairment that impedes study compliance * Skin conditions (i.e. burns or poor skin coverage) as well as those with severe contractures that prevent prior prosthetic we…
Interventions
- DeviceSuction Suspension First
Participants will be fit with a socket capable of being suspended by both traditional suction and elevated vacuum. Participants will be assessed first with the elevated vacuum system inactive (traditional suction). Residual limb kinematics and skin deformation during movement tasks will be evaluated utilizing dynamic stereo x-ray. The evaluation will then be repeated with the elevated vacuum system active.
- DeviceElevated Vacuum Suspension First
Participants will be fit with a socket capable of being suspended by both traditional suction and elevated vacuum. Participants will be assessed first with the elevated vacuum system active. Residual limb kinematics and skin deformation during movement tasks will be evaluated utilizing dynamic stereo x-ray. The evaluation will then be repeated with the elevated vacuum system inactive.
Location
- VA NY Harbor Healthcare System, New York, NYNew York, New York