What role does friction play in pressure ulcers?
Recently, the National Pressure Ulcer Advisory Panel released a white paper titled, “Friction Induced Skin Injuries — Are They Pressure Ulcers?” addressing many questions regarding friction.
All long-term care nurses and other direct caregivers need to be aware of friction and its dangers.
The NPUAP white paper defines friction as the rubbing together of one body against another, or the force that resists relative motion between two bodies in contact and/or material elements sliding against each other. Static and dynamic are the two types of dry friction.
Static friction is the force resisting the relative motion between two bodies when there is no sliding, the white paper’s authors explain. Dynamic friction is the force resisting movement between two bodies in contact as they are moving relative to one another (that is, sliding).
The paper’s authors ask a good question: Does friction alone cause a pressure ulcer? They say no. Friction is a risk factor, but does not singularly or directly cause a pressure ulcer.
Friction is a significant factor in pressure ulcer development because it acts in concert with gravity to cause shear. The effect of the two factors is synergistic. It is not possible to have shear without friction. However, it is possible to have friction without significant shear (such as from moving the heels repeatedly against the bed sheets).