What is Shear Force?

Shear is an action or stress resulting from applied forces which causes or tends to cause two contiguous internal parts of the body to deform in the transverse plane.

Load has an internal effect or influence on the tissue and will occur even when lying flat. If pressure remains constant and shear increases, the deformation of soft tissue may be greater. Change in position are likely to cause shear- for example when the head of bed is raised or lowered.

Tissue Distortion due to Pressure