Pressure ulcers (PUs), also known as bed sores, pressure sores or pressure injury, are defined as: localized injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure, or pressure in combination with shear (National Pressure Ulcer Advisory Panel [NPUAP], European Pressure Ulcer Advisory Panel [EPUAP], Pan Pacific Pressure Injury Alliance [PPPIA], 2014).