Trabecular Bone Reinforces Bone Capability to Withstand Off-axis Loading
Poster Number
35
College
College of Arts and Sciences
Department
Biology
Faculty Mentor
Dr. Meir Barak, D.V.M.
Abstract
Previous studies show that trabecular bone responds to external loading by adjusting its structure to optimize resistance to the principle direction of loading (‘Wolff’s law’). Yet, each trabecular bone sample is unique and delicate and can only be tested once before failure. So far, it has been practically impossible to test a sample multiple times in different directions to find its optimal mechanical orientation. Here, we present a novel 3D printing approach to determine the stiffness and strength of a trabecular sample in multiple orientations. A micro-CT scan from a sheep talus was reconstructed to create a 3D computer model. Next, the micro-CT reconstruction was tilted ten degrees along the sagittal plane and a new model was created. This sequence was repeated nine times, rotating the reconstruction an additional ten degrees, to a final tilt of 90 degrees. Each model was 3D printed ten times and the tested in compression until failure. Our results show that contrary to the accepted paradigm, trabecular structure is significantly stiffer and stronger between 40-80° relative to the axial axis. These results differ from the common belief that trabecular bone optimizes its structure along the principle loading axis of the bone and implies that it has a major role in maintaining bone integrity when it is loaded off-axis (e.g. a fall or abnormal loading). Our study introduces new and unexpected results which may change the way trabecular bone structure and function is understood.
Previously Presented/Performed?
Summer Undergraduate Research Experience (SURE) Symposium, Winthrop University, July 2015
Start Date
22-4-2016 2:15 PM
End Date
22-4-2016 4:15 PM
Trabecular Bone Reinforces Bone Capability to Withstand Off-axis Loading
Richardson Ballroom
Previous studies show that trabecular bone responds to external loading by adjusting its structure to optimize resistance to the principle direction of loading (‘Wolff’s law’). Yet, each trabecular bone sample is unique and delicate and can only be tested once before failure. So far, it has been practically impossible to test a sample multiple times in different directions to find its optimal mechanical orientation. Here, we present a novel 3D printing approach to determine the stiffness and strength of a trabecular sample in multiple orientations. A micro-CT scan from a sheep talus was reconstructed to create a 3D computer model. Next, the micro-CT reconstruction was tilted ten degrees along the sagittal plane and a new model was created. This sequence was repeated nine times, rotating the reconstruction an additional ten degrees, to a final tilt of 90 degrees. Each model was 3D printed ten times and the tested in compression until failure. Our results show that contrary to the accepted paradigm, trabecular structure is significantly stiffer and stronger between 40-80° relative to the axial axis. These results differ from the common belief that trabecular bone optimizes its structure along the principle loading axis of the bone and implies that it has a major role in maintaining bone integrity when it is loaded off-axis (e.g. a fall or abnormal loading). Our study introduces new and unexpected results which may change the way trabecular bone structure and function is understood.
