The proposed research will challenge the standard approach to lumbar interbody fusions (LIFs) by utilizing medical imaging, finite-element (FE) models and emerging materials to guide novel device design. These fusions are performed annually on 500,000 patients who suffer from degenerative disc disease, instability, and scoliosis. This proposal offers an innovative, multi-disciplinary approach to studying LIFs. Conventional CT will be correlated and utilized to predict local strength and modulus values across the endplates. These data will also be used to create patient-specific, FE models with the matching material properties. FE simulations will be used to evaluate the complex biomechanics of the spine for a wide variety of cages/rod designs, materials, and configurations. Furthermore, simulations will yield valuable information regarding the stress distribution across the endplates as well as overall construct stiffness as a function of bone formation and fusion. Lastly, poly(para-phenylenes) (PPPs) are a new class of aromatic polymers with strength and modulus values higher than poly(ether-ether-ketone) (PEEK). PPPs have superior manufacturability compared to current cage materials and will be made into porous devices. The porosity of the device will be spatially tailored to match the properties of the implant across the endplates, while also promoting osteointegration of bone. Our hypothesis is that a porous interbody fusion cage would reduce complications (subsidence and adjacent-level disease) and improve clinical outcomes by (1) spatially tailoring the modulus of the implant to the endplate, (2) more evenly distributing stresses across the entire endplate, (3) lowering the overall construct stiffness value, and (4) allowing for osteointegration of bone into the implant. If successful, the proposed research would shift the paradigm for how LIF cages and constructs are designed as well as lower rates of subsidence, implant failures, and adjacent-level disease. The proposed team consists of an inter- disciplinary group with backgrounds in clinical surgery, mechanical and biomedical engineering, and materials science.

Public Health Relevance

Primary care physicians report that back pain is the second most common complaint next to the common cold. The total cost of back pain has been estimated to cost the United States between $100 and $200 billion annually. These costs have been calculated from the direct costs of surgery and the indirect costs of lost wages, reduced productivity, and cost of care. A majority of this pain stems from the lumbar (low-back) region of the spinal column.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AR065713-01
Application #
8622921
Study Section
Bioengineering, Technology and Surgical Sciences Study Section (BTSS)
Program Officer
Panagis, James S
Project Start
2014-04-01
Project End
2016-03-31
Budget Start
2014-04-01
Budget End
2015-03-31
Support Year
1
Fiscal Year
2014
Total Cost
$172,230
Indirect Cost
$59,133
Name
University of Colorado Denver
Department
Engineering (All Types)
Type
Schools of Engineering
DUNS #
041096314
City
Aurora
State
CO
Country
United States
Zip Code
80045