Giambini, HugoTreviño, Jose Hernandez, III2024-03-082024-03-082023https://hdl.handle.net/20.500.12588/5973This item is permanently embargoed and is not available for download.The current course of treatment for rotator cuff tears depends on numerous factors, such as tear size, intramuscular fatty infiltration, metabolic diseases, muscular atrophy, age, and muscle stiffness. These multiple factors affecting muscles and tendons are evaluated in the clinical setting via various diagnostics imaging tools and physical manipulations of the shoulder. However, current clinical methods present several limitations that prevent a comprehensive, quantitative, and accurate estimation of muscle properties and rotator cuff tear prognosis. As a result, treatment for such defects that have failed conservative management depends solely on surgical techniques. Thus, novel non-invasive imaging approaches that quantify muscle properties should be developed to aid clinicians during surgical planning and implementation of rehabilitation protocols. Furthermore, novel therapeutics should be designed to improve muscle quality and reduce the high rates of repair failures. For this purpose, the goal of the current study was twofold: first, to develop imaging approaches to quantify the properties of the rotator cuff muscles to improve diagnosis and rehabilitation management; second, to investigate the feasibility of novel therapeutics that can be used for muscle regeneration. The objectives of the current study were to quantify the degenerative properties (i.e., volumetric intramuscular fatty infiltration, atrophy, and stiffness) using magnetic resonance imaging (MRI) and ultrasound shear wave elastography (SWE) imaging of the rotator cuff muscles and to determine the response of skeletal muscle precursor cells when exposed to therapeutics involved in age-associated cell dysfunction. We have developed the following aims to reach our goal and objective: Specific Aim 1: Quantify the volumetric distribution of degenerative properties in the supraspinatus muscle using novel magnetic resonance imaging techniques. Specific Aim 2: Determine the role and activity of the individual sub-regions of the infraspinatus muscle and teres minor muscle using ultrasound shear wave elastography during external shoulder rotation. Specific Aim 3: Evaluate the effect of novel therapeutic interventions on muscle regenerative properties. Successful outcomes from this study will allow for a more comprehensive and quantitative evaluation of skeletal muscles and pave the way for developing novel therapeutics that can restore muscle function, eventually reducing the high incidence of repair re-tears.178 pagesapplication/pdfBiomedical engineeringBiomechanicsBioengineeringThesis