Novel Imaging Of Human Fascia in vivo Using Advanced MRI

Abstract

Fascia is an abundant connective tissue that may be involved in force transmission in ways that are poorly understood. Prior experiments suggest that fascia may play a consid- erable role on musculoskeletal force distribution in animals and humans. There is a growing interest in modelling the mechanical contribution of this tissue, which is challenging con- sidering the thin structure of the tissue and the difficulty of obtaining details from imaging. Here, I use advanced MRI to image the fascia in vivo to create physics-based simulations to explore fascia mechanics and probe its role in force transmission in the musculoskele- tal system. This thesis comprises four primary studies: firstly, the development of an MRI protocol for human fascia, followed by the application of image processing techniques to enhance image quality; an in vivo assessment of fascia and surrounding lower leg muscles in adult humans, followed by the building of a finite element geometry of several lower leg muscles and its surrounding fascia to probe the biomechanics of the tissue. In this work, using advanced MRI, this novel study involves the successful imaging of lower limb fascia in high resolution. This MRI protocol was used to image 30 healthy volunteers to create a first-ever in vivo human fascia dataset. Using this dataset, I measure human fascia thickness in vivo and show that these are consistent with available literature from dissection studies which ranges from 0.7-1.1 mm. Finite element simulations demonstrate that the presence of fascia may increase the forces transmitted from muscle to tendon compared to a system that lacks fascia. We conducted simulations on different lower limb muscles to understand the impacts of different muscle architecture, and consistently, the simulation results arrive at the same conclusion. This work is the first to my knowledge to take advantage of in vivo MRI of human fascia and build physics-based models to explore human muscle-fascia biomechanics.