Composition and Mechanical Characteristics of Soft Tissue - Soft tissue is composed of collagen, elastin, and ground substance. - Fibroblasts are responsible for producing soft tissue fibers and ground substance. - Elastin confers stiffness to the tissue, while collagen limits deformation and protects tissues from injury. - Human soft tissue is highly deformable and its mechanical properties vary among individuals. - Stiffness and damping resistance of soft tissue are correlated with the mass, velocity, and size of the striking object.

Pseudoelasticity and Residual Stress in Soft Tissue - Soft tissues exhibit viscoelastic properties but can be approximated by a hyperelastic model after preconditioning to a load pattern. - Preconditioned soft tissues still present hysteresis, so the mechanical response can be modeled as pseudoelastic. - Soft tissues usually have residual stress in their physiological state, which may be released when the tissue is excised. - Physiologists and histologists must be aware of residual stress to avoid mistakes in tissue analysis.

Remodeling and Growth of Soft Tissue - Soft tissues can grow and remodel in response to chemical and mechanical changes. - Fibroblasts produce tropocollagen at a rate proportional to these stimuli. - Remodeling plays a role in soft tissue diseases, injuries, and changes in mechanical load. - Growth and remodeling are involved in the thickening of cardiac muscle in response to increased blood pressure. - Mechanobiology studies the relationship between stress and growth at the cellular level.

Imaging Techniques for Soft Tissue Visualization - Choosing an imaging technique for visualizing soft tissue extracellular matrix (ECM) components requires considering factors such as resolution, contrast, artifact count, and volume data acquisition. - Transmission Light, Confocal, Multi-Photon Excitation Fluorescence, Second Harmonic Generation, and Optical coherence tomography are different imaging methods with varying properties and resolutions. - The resolution of the imaging technique needs to be approximately 0.5 μm to capture the 1-2 μm thick collagen fibers. - Volume data acquisition allows following fiber bundles across the volume. - Fixation of soft tissue in formalin can cause shrinkage and alter the tissue structure.

Soft Tissue Disorders and Sarcomas - Soft tissue disorders affect soft tissues in the body and can be difficult to treat and diagnose. - Soft tissue therapy is an expanding field, and platelet-derived growth factor shows promise in treating soft tissue injuries. - Soft tissue disorders and rheumatism have overlap, and soft tissue rheumatic disorders is a term used to describe these conditions. - Rheumatologists specialize in treating soft tissue rheumatic disorders, which can cause chronic pain and difficulty in diagnosis. - Soft tissue sarcomas are types of cancer that develop in soft tissues and can occur in various parts of the body. - Diagnosis of soft tissue sarcomas involves imaging and biopsy, and treatment options include surgery, radiation, and chemotherapy. - The prognosis for soft tissue sarcomas depends on various factors.