Posted October 25, 2021
  • | Heel Protectors

Shear Madness: Friction, Shear and Chronic Wounds

Skin tears are traumatic wounds caused by mechanical forces at work. 

Friction and shear. While both go hand in hand, friction and shear involve distinct forces with varied outcomes and understanding the difference is imperative. Friction alone is not a causative factor in the development of pressure injuries, but it certainly has a supporting role. 

Friction is a mechanical force exerted when skin is dragged across a surface. The result of a friction injury affects the superficial layers of the skin and can present as an abrasion, like a ‘rug burn’.  But be careful. It’s easy to mistake a friction injury for a pressure injury. Friction increases the susceptibility of pressure injury development by damaging the epidermal skin layer, but it’s not the primary cause. 

Shear, on the other hand, is a mechanical force exerted parallel to the skin or body’s surface. It occurs when pressure is exerted in one direction and the skin moves in the opposite direction. This internal pressure coupled with soft tissue and blood vessel distortion can result in a pressure injury from shear forces. For example, when in bed the lower spine presses down, compromising blood supply. Elevating the head of the bed can cause sliding, creating opposite forces between the skin and the support surface— or shear forces.  Shear injuries occur inside the body and initially are not visible at the surface of the skin.

The resulting damage of friction and shear are skin tears. Skin tears are traumatic wounds caused by these mechanical forces at work.  They are most common in populations with fragile skin like the elderly or critically ill. The International Skin Tear Advisory Panel (ISTAP) classifies skin tears into three specific types from least severe to greatest. Type one involves a linear or flap tear that can be repositioned over the wound bed. No skin is lost in type one skin tears. Type two comprises a partial flap loss that cannot be used to cover the wound bed. And type three involves a total flap loss fully exposing the wound. Skin tears are acute wounds that can lead to chronic wounds if not properly managed. But patients have to be moved – so how can it be done safely? 

Move the surface, not the patient. Those with fragile skin may require occasional transfers but causing new injuries while treating others is not an option. The versatility of the WAFFLE Overlay allows caregivers to boost, reposition and transfer patients on the carts while maintaining skin integrity. Shearing forces are not inflicted on those at risk and patients remain protected throughout their hospital journey. It’s great to provide options. Find the ideal support solutions to protect the skin on the inside and out.