Trunk Stability and Seated Reaching After Spinal Cord Injury
Abstract
Background/Readiness: Spinal cord injury (SCI) can result in paralysis of the torso and pelvis that can lead to unhealthy and non-functional seated postures which in turn result in other complications such as: pressure sores, respiratory problems, and the inability to manipulate objects and complete activities of daily living. Trunk stability has been identified as one of the highest priorities for motor system recovery in individuals with SCI regardless of injury level, indicating its central importance for a broad cross section of the population. Objective/Hypothesis: The overall goal of this expansion project of grant W81XWH-17-1-0240 (Enhancing seated stability and reaching after spinal cord injury) is to leverage the achievements made with prior Spinal Cord Injury Research Program support to transfer our seated balance and assisted transfer control systems to the Network Neuroprosthesis (NNP) platform, verify the control systems in a series of laboratory experiments, and prepare the trunk control package for future clinical dissemination and commercialization. The new control systems will be available to a wider population of individuals paralyzed by SCI by seeking regulatory Investigational Device Exemption (IDE) approval from the Food and Drug Administration (FDA) that will extend the NNP to individuals with paraplegia due to SCI all in preparation for ensuing clinical trials. Specific Aims: The specific aims of the project are: (1) Estimate global orientation metrics for trunk and pelvis pose by fusing signals from a variety of implanted inertial measurement unit (IMU) sensors of the NNP and assess their suitability as feedback signals for controlling seated posture, improving balance and extending reach in persons with complete or partial paralysis. (2) Implement advanced feedback control systems that assure robust seated stability, balance, and reach, and facilitate efficient wheelchair propulsion, transfers and other activities of daily living in NNP recipients. Additional activities include preparing, submitting, and receiving approval from the FDA for an Early Feasibility Study trunk system IDE applicable to paraplegics. Study Design: Anatomically realistic three-dimensional musculoskeletal models along with sophisticated optimization and machine learning algorithms will be utilized to obtain robust estimates of trunk orientation from a number of randomly implanted IMU sensors embedded in the NNP stimulation modules. Using this as feedback signal, the controllers for regulating seated posture will be returned and tested in a series of realistic activities of daily living that involve typical work and home activities, wheelchair propulsion, and assisted transfers. The self-righting controllers allow users to move their trunk far away from the erect posture and then restore that posture to erect, the posture-changing controllers will enable users to set their trunk postures in any location in the seated workspace at their will, the disturbance-rejection controllers will maintain the selected posture at its desired location even when the trunk and pelvis are subjected to small disturbances from externally applied perturbations or internally generated voluntary arm movements. Finally, the assisted transfer controllers will assist caregivers in aiding SCI individuals to transfer with minimal long-term injuries to the caregivers’ shoulders and back. Impact: A neuroprosthesis designed specifically to control trunk posture will dramatically increase the level of independence of individuals with SCI by enabling use of both arms to undertake bimanual tasks while seated and expanding seated workspace and the ability to reach and manipulate objects in the environment. In addition, it will lead to increased autonomy and ability to perform activities of daily living, as well as a reduction in healthcare costs by minimizing the risks of pressure sores and other complications associated with fixed and u
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Dec 28, 2022
- Source ID
- W81XWH2210836
Entities
People
- Musa Audu
Organizations
- Case Western Reserve University
- United States Army