Researcher(s)
- Alexander Broadhurst, Biomedical Engineering, University of Delaware
Faculty Mentor(s)
- Stephanie Cone, Biomedical Engineering, University of Delaware
Abstract
Osteoarthritis (OA) affects joint structure and function, including changes within articular cartilage, subchondral bone, ligaments, capsule, synovial membrane, and periarticular membrane [1]. To better understand the severity and effects of OA on skeletal structure, past research has employed microCT and histology [2] while MRI has been used to non-destructively characterize soft tissues in healthy and injured states. Currently, MRI has not been frequently used in small animal models due to the need for fine resolution to discern between the tissues in the knee. Mouse and rat models are often used because they share similar anatomical and physiological makeup as humans. To determine the baseline morphological characteristics of rodent models, high field MRI scans were taken of mouse and rat knee joints. MRI segmentations were performed using Simpleware (Synopsis), a software that generates 3D models of imaged anatomy. Segmented parts included the femur, tibia, menisci and ligaments. The tibial plateau was identified, and the volume of this region was determined. Cross sectional area was calculated by dividing the corresponding slice height. Comparing areas from one specimen to another allowed for a quantitative comparison between both rodent species, signifying that a rat’s tibia had a cross sectional area six times greater than that of a mouse. In addition to the tibial plateau, femur and tibia long bone 3D models were analyzed in Matlab to calculate cross sectional area. The data suggests that both rat and mouse tibias have smaller cross sectional areas than femurs. In the future, healthy anatomical structures of these rodents will be compared to those with OA. After identifying these morphological differences, mechanical testing (six degrees of freedom) will be performed to further investigate diseased rodent knee function.