The Mechanical Properties of Mice Tibial Mid-Diaphysis is Sex and Age Independent
Poster Number
46
College
College of Arts and Sciences
Department
Biology
Faculty Mentor
Meir Barak, Ph.D., D.V.M.
Abstract
Bone is a classified organ that continuously undergoes modeling based on the load it experiences. The aim of this study was to examine these changes in the cortical bone of male and female mice across two age groups. In order to do this, twenty-five sections of the mid-diaphysis were cut from the tibiae of eight male and seventeen female mice. Bones from both sexes were then categorized as either “old” or “young,” depending on their age (up to 2 months for young and older than 3 months for old). These cortical samples were then loaded in compression using an Instron 5942 universal testing machine, in order to determine (1) whether or not there was any significant difference in the material and structural properties of male versus female cortical bone and (2) if these differences had any correlation with the age of the mice. All samples were loaded until fracture and a stress-strain curve was generated, from which the values for stiffness, strength, and Young’s Moduli were obtained. The average stiffness was 1058.4 ± 487.2 N//m versus 855 ± 342 N/m; the average Young’s Modulus was 529.3 ± 243.8 MPa versus 427.5 ± 170.9 MPa; and the average strength was 12.9 ± 4.6 MPa versus 11.3 ± 4.6 MPa for the young and old samples, respectively. Our results imply that the mechanical properties of mice tibial mid-diaphysis does not differ between male and female and does not change with age. These results could be due to the low bodyweight of mice and the low stresses their bones experience, leading to low modeling activity.
Start Date
21-4-2017 2:15 PM
The Mechanical Properties of Mice Tibial Mid-Diaphysis is Sex and Age Independent
Richardson Ballroom
Bone is a classified organ that continuously undergoes modeling based on the load it experiences. The aim of this study was to examine these changes in the cortical bone of male and female mice across two age groups. In order to do this, twenty-five sections of the mid-diaphysis were cut from the tibiae of eight male and seventeen female mice. Bones from both sexes were then categorized as either “old” or “young,” depending on their age (up to 2 months for young and older than 3 months for old). These cortical samples were then loaded in compression using an Instron 5942 universal testing machine, in order to determine (1) whether or not there was any significant difference in the material and structural properties of male versus female cortical bone and (2) if these differences had any correlation with the age of the mice. All samples were loaded until fracture and a stress-strain curve was generated, from which the values for stiffness, strength, and Young’s Moduli were obtained. The average stiffness was 1058.4 ± 487.2 N//m versus 855 ± 342 N/m; the average Young’s Modulus was 529.3 ± 243.8 MPa versus 427.5 ± 170.9 MPa; and the average strength was 12.9 ± 4.6 MPa versus 11.3 ± 4.6 MPa for the young and old samples, respectively. Our results imply that the mechanical properties of mice tibial mid-diaphysis does not differ between male and female and does not change with age. These results could be due to the low bodyweight of mice and the low stresses their bones experience, leading to low modeling activity.
