Definition - “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”.

Fast Facts

  • Occurs when the patient is lying flat and increases with lateral movement
  • Tissue deformation may increase when constant pressure and shear forces are present
  • Increased shear forces can exacerbate tissue damage
  • Shear inflicted ulcers often present with a shallow area that progresses to a depth represented by bruising. Skin edges may also be ragged
  • Shear forces tend to cause deeper tissue damage which may not be immediately visible
  • Changes in position are likely to cause shear – for example when the head of bed is raised or lowered