Effect of Continuous and Intermittent Mechanical Loading on the Development of Skeletal Muscle Damage - A Combined Experimental/Numerical Approach

Prolonged mechanical loading of soft tissues, as present when individuals are bedridden or wheelchair-bound, can lead to degeneration of skeletal muscle tissue. This can result in a condition termed pressure-related deep tissue injury (DTI), a severe kind of pressure ulcer that initiates in deep tissue layers, e.g. skeletal muscle, near bony prominences and progresses towards the skin. Complications associated with DTI include sepsis, renal failure, and myocardial infarction. Damage pathways leading to DTI involve ischemia, ischemia-reperfusion injury, impaired lymphatic drainage, and sustained tissue deformation. Recently, the role of tissue deformation in the onset of skeletal muscle damage was established by combining animal experiments with finite element (FE) modeling [1]. After 2 hours of continuous loading, a clear correlation between maximum shear strain and damage was found.