Pressure ulcers, also known as bedsores or decubitus wounds, affect over one millions adults every year. The wounds can range from superficial and mildly red on the skin surface to an extremely infected, deep, open wound penetrating down to the bone with blackened or dead tissue. These models illustrate all found wound stages and are used to give instruction on the care and cleaning of the ulcers.
The four stages include:
Stage 1 - Reddening, unbroken skin
    Stage 2 - Open wound that is reddened with partial skin loss
    Stage 3 - Deep, open wound that reaches through all layers of skin and into the muscle
    Stage 4 - Sever, deep, open wound that reaches through all layers of skin and damages muscle, bone, tendons and joints