The applicant's long term research objectives are to use advanced technology to help improve the quality of life of wheelchair users, especially those with disabilities from spinal cord injury (SCI). More specifically, the applicant sets his target at preventing the soft tissue breakdown, the most common secondary complication of wheelchair sitting, by reducing or eliminating risk factors. In the US, nearly 50% of the 1.4 million people who rely on wheelchairs for mobility develop serious tissue breakdown at pressure point areas such as the ischia and the greater trochanters. This has a detrimental impact on the quality of life of the affected population and imposes a tremendous economic burden to health care. In this study, the applicant focuses on development and optimization of the sophisticated computational finite-element (FE) modeling theory and technology to investigate the soft tissue response to external sitting loads. The proposed FE models will simulate the load-bearing condition as in real sitting. It is expected that the models will not only be powerful tools for better understanding the response of soft tissues to sitting loads, but they will also facilitate development of improved prevention and treatment strategies against the soft tissue breakdown.
Aim 1 : To develop and refine the methodology for establishing the geometry of FE models for the buttock-thigh. The methodology implements a true representation of the anatomical geometry of buttock-thigh structure in actual sitting. Four versions of these models will be established representing males and females, each including able-bodied and chronic spinal cord injury (SCI) individuals. The models will also be calibrated and validated.
Aim 2 : To implement into the FE model the experimentally acquired mechanical properties of biological soft tissue (both human and experimental animal) under healthy, wounded, and SCI conditions;to investigate the sensitivity of the FE modeling to the variation of the material properties and the contact behavior among tissue layers;and to investigate the variation of buttock tissue properties in intact and SCI populations.
Aim 3 : To evaluate the buttock tissue internal mechanical environment in the sitting posture in individuals with chronic SCI using the validated FE models, and compare the FE model predictions with those obtained from the able-bodied controls. Relevance to Public Health: This research will provide a better understanding of the etiology of soft tissue breakdown in wheelchair sitting and help finding better strategies of treatment and prevention.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Mentored Quantitative Research Career Development Award (K25)
Project #
5K25HD051983-04
Application #
7802313
Study Section
Pediatrics Subcommittee (CHHD)
Program Officer
Quatrano, Louis A
Project Start
2007-06-10
Project End
2012-05-31
Budget Start
2010-06-01
Budget End
2011-05-31
Support Year
4
Fiscal Year
2010
Total Cost
$143,453
Indirect Cost
Name
Northwestern University at Chicago
Department
Physical Medicine & Rehab
Type
Schools of Medicine
DUNS #
005436803
City
Chicago
State
IL
Country
United States
Zip Code
60611
Makhsous, Mohsen; Lin, Fang; Cichowski, Andrew et al. (2011) Use of MRI images to measure tissue thickness over the ischial tuberosity at different hip flexion. Clin Anat :
Lin, Fang; Pandya, Atek; Cichowski, Andrew et al. (2010) Deep tissue injury rat model for pressure ulcer research on spinal cord injury. J Tissue Viability 19:67-76
Makhsous, Mohsen; Lin, Fang; Pandya, Atek et al. (2010) Elevation in the serum and urine concentration of injury-related molecules after the formation of deep tissue injury in a rat spinal cord injury pressure ulcer model. PM R 2:1063-5
Makhsous, Mohsen; Lim, Dohyung; Hendrix, Ronald et al. (2007) Finite element analysis for evaluation of pressure ulcer on the buttock: development and validation. IEEE Trans Neural Syst Rehabil Eng 15:517-25